Beiser

Beiser’s book grows out of the renewed interest in neo-Kantianism in the English speaking world. Scholars have slowly realised that one of the most influential movements of the late nineteenth and early twentieth centuries was badly neglected. The revival is evident in recent collections and a series of conferences. Beiser attended the meetings at MIT and Cornell and helped to plan them. He had to miss the Cambridge meeting for family reasons. The energy and arguments in those gatherings pushed him to write this book. Although the book is meant as an introduction it has a large aim. Beiser wants to explain the main ideas of the leading neo-Kantians from the 1790s through the 1880s, that is, before the movement became an academic fixture later in the nineteenth century. His subject is the neo-Kantians before neo-Kantianism became a set of formal schools. He focuses on the origins of the movement, why it arose as a reaction against speculative idealism at the end of the eighteenth century, and how it answered the cultural crises of the mid nineteenth century. His method is old fashioned on purpose. He reads the central texts by the major figures and tries to understand their key ideas in their historical setting. He does not give an institutional history of the schools, nor does he map in detail the social and political forces behind the movement. Those approaches have value, but he argues that we still lack the basic philosophical map in English. Many of the main figures and their works have not been treated properly, so he gives priority to the ideas themselves while still using context when it helps to show how those ideas took shape. The field is still young. Two scholars in particular have pushed it forward with excellent studies of the movement’s beginnings and of the Marburg school. Comparable work is needed on the Baden and Goettingen strands, and much correspondence still needs to be recovered. A great deal has been lost, but some early letters survive, for example from Fries, Herbart and Beneke. For later figures far less survives. Hermann Cohen’s letters are brief because his family archive was destroyed. Beiser would like German scholars to help repair this gap in their cultural record. He owes many debts, which are recorded in the notes. He has learned most from Klaus Christian Köhnke, even where he disagrees. Conversations over the years with many colleagues have also shaped the project. As he was finishing, the Cambridge conference volumes on idealism appeared. They range more widely than this book. Beiser presents his book as a companion that focuses on neo-Kantianism in the narrower, scholastic sense. He sets out a simple map. In historical terms, neo-Kantianism was the nineteenth century German movement to revive Kant’s philosophy. It dominated German academic philosophy in the final decades of that century and influenced Italy, France, Britain and Russia. Its golden age ran from about 1860 to 1914. In those years serious training in philosophy meant serious work on Kant. The lecture and publication record shows a surge in courses and books on Kant, and by 1870 most German universities had at least one neo-Kantian professor. People usually divide the movement into three schools. There was the Marburg school with Cohen, Natorp and Cassirer. There was the Southwestern or Baden school with Windelband, Rickert and Lask. There was also the neo-Friesian school at Goettingen under Leonard Nelson. The main university centres were Marburg, Goettingen, Strasbourg and Heidelberg, with Berlin becoming important later. Beiser cautions against reducing the whole movement to these three schools. They formed fairly late, after the core arguments had been forged, and several decisive figures stood outside them, including Helmholtz and others who are too easily forgotten if one looks only at school labels. The key formative decade was the 1860s. There had been earlier manifestos, but in the 1860s a wave of young philosophers produced essays and books that put Kant back at the centre. Five figures were especially important in that effort, and Beiser discusses them later. Older scholarship liked to say that neo-Kantianism begins in the 1860s with Otto Liebmann’s slogan back to Kant. That view is only half right. Liebmann’s book capped a series of earlier calls to return to Kant, and even the famous slogan was already in the air. Beiser’s claim is that the roots go back to the 1790s, before Kant’s death. The founding fathers were Jakob Friedrich Fries, Johann Friedrich Herbart and Friedrich Eduard Beneke. They all called themselves Kantians and urged a return to the spirit of Kant. They laid down many of the ideas that later defined the movement, such as the importance of Kant’s dualisms, the limit of knowledge to experience, the central role of critical analysis, and the need for philosophy to follow rather than lead the natural sciences. It may sound odd to trace neo-Kantianism to the eighteenth century when the name suggests a revival after a decline. But Kant’s prestige did begin to dip already in the early 1790s as Reinhold’s elementary philosophy and Fichte’s system took hold. To the young Romantics Kant looked old fashioned. Pushback against Reinhold, Fichte and Schelling began before Hegel’s rise and is already clear in Fries’s 1803 book, which in many ways is the sourcebook for the later movement. Why neo-Kantianism rose and became so strong in the second half of the nineteenth century is, in Beiser’s account, a matter of both culture and argument. Two broad cultural forces helped. German nationalism made Kant a source of pride and identity. Historicism encouraged scholars to look back to decisive origins, and Kant clearly marked a turning point. Those forces explain why people looked again at Kant, but they do not explain why neo-Kantianism won the day. It had to succeed in argument against its rivals. One rival was speculative idealism. By the middle of the century that tradition had lost momentum for many reasons, including strong internal criticism. The fall of Hegelianism left a vacuum. Neo-Kantianism then offered a positive programme that seemed to answer two urgent debates of the time. The first was the identity crisis of philosophy after the rise of the empirical sciences. What was philosophy still for. The neo-Kantian answer was that philosophy should become epistemology in a strict sense, not a master science over nature, but a reflective study of the methods and presuppositions of the sciences. That made philosophy useful and distinct without pretending to legislate for physics or biology. The second was the materialism controversy. Popularisers of science claimed that materialism was the new creed. Neo-Kantians argued that materialism could not explain consciousness and that it took matter for granted without examining the conditions of knowledge. They defended the autonomy and rationality of the moral sphere while fully backing scientific inquiry. By the 1870s they seemed to have beaten both speculative idealism and crude materialism. No victory lasts forever. A new challenge came from Schopenhauer, who offered a rival answer to the identity crisis. For him philosophy had to face the problem of existence head on, not only the methods of knowledge. His popularity forced neo-Kantians to broaden their view. From the late 1870s they put more weight on ethics and on a general outlook on life rather than on epistemology alone. Beiser clears away several common myths. Many assume neo-Kantianism was mainly a scholarly revival of Kant philology. He argues that it was a philosophical movement first. It aimed to vindicate Kant’s conception of philosophy and his transcendental method. Others say the neo-Kantians were mere disciples. They were not. They were often severe critics of Kant and used him for their own projects, sometimes appealing to the spirit rather than the letter of his work. Another story paints neo-Kantians as safe academics while the real rebels were Marx, Kierkegaard and Nietzsche. That story misses that many neo-Kantians were outsiders for much of their careers and that from the late 1870s they turned to moral, political and aesthetic questions. A further myth, spread in the twentieth century, treats neo-Kantianism as if it rested on a picture of the mind as a mirror of nature and on a foundational project for all science. In fact most neo-Kantians rejected foundationalism. They did not think philosophy could supply first principles for the sciences. They thought the sciences were autonomous facts, and that philosophy should clarify their logic, not ground them. To explain the genesis of the movement Beiser recovers a forgotten tradition from the turn of the nineteenth century. Fries, Herbart and Beneke formed an alternative idealist line that opposed the speculative projects of Fichte, Schelling and Hegel. They shared a loyalty to transcendental idealism, a plan to reform theory of knowledge with the help of psychology, mistrust of grand metaphysics, respect for the methods of the exact sciences, an ethics linked to aesthetics, and resistance to speculative systems. Their tradition dropped out of standard histories because Hegel and his followers wrote the script, and later historians repeated it. In reality there were two post-Kantian lines. The speculative rationalists pushed deductive and dialectical method and aimed at absolute idealism. The empirical psychological line kept to subjective idealism and insisted on experience, on Kant’s dualisms and on the separation of theoretical and practical reason. Both lines claimed Kant’s authority. With hindsight we can see that each stretched one side of Kant against the other. The speculative line pressed systematic unity and a priori method. The empirical line pressed the limits of experience and the need for content from the senses. Each accused Kant of leaning too far the other way. The later victory of the neo-Kantians was in effect the victory of that empirical psychological tendency. It fit an age shaped by the natural sciences and it kept philosophy from overreaching. This older line has often been dismissed as psychologistic. Beiser argues that the charge is too crude. Fries, Herbart and Beneke distinguished clearly between norms of reasoning and psychological facts. They did not reduce logic to psychology. What they did say was that psychology matters for understanding how knowledge is possible and how the sciences in fact work. They wanted philosophy to give up the fantasy of being first philosophy and instead to serve as the underlabourer to the sciences, clarifying methods and assumptions. The deeper background goes back to the Scottish Enlightenment project of a science of human nature, which German thinkers called anthropology. That project treated human beings as part of nature and sought laws of mind by observation and history. Kant himself began with anthropology before he turned to transcendental method. Fries and Beneke picked up that thread and tried to combine Kant’s revolution with a modern empirical psychology, not the old faculty psychology of Wolff. In that way they prepared the ground for neo-Kantianism as it took shape later in the century. What follows in the rest of Beiser’s book is a close reading of the early writings of Fries, Herbart and Beneke up to the point where they discover Kant and first set out their neo-Kantian ideas. He does not try to cover their whole philosophies. He aims to show how their efforts gave the movement its first shape and why they deserve a central place in its story. Fries’s philosophy begins with Kant but moves by method rather than by substance. He accepts the full Kantian framework: the thing in itself, the divide between the phenomenal and the noumenal, the split between understanding and sensibility, and the threefold structure of mind into cognition, volition, and feeling. He keeps Kant’s metaphysical deduction and table of categories intact. His aim is not to rewrite Kant’s doctrines but to rebuild their foundation. By the early nineteenth century, Fries was recognised as the leading Kantian in Germany. Those who resisted the speculative metaphysics of post-Kantian idealism and defended the critical spirit against the new rationalism and romantic Naturphilosophie found in him an ally. Fries’s significance, however, extends far beyond his own lifetime. Few philosophers inspire two separate revivals, yet Fries did. The first Friesian School, founded in Jena in 1847 by Ernst Friedrich Apelt, gathered leading scientists and mathematicians who shared Fries’s belief that philosophy should clarify the logic of science. The second, led by Leonard Nelson in 1903, produced figures such as Rudolf Otto, Arthur Kronfeld, and the Nobel laureate Otto Meyerhof. Both schools reissued the Abhandlungen der Fries’schen Schule, reaffirming their commitment to Kant as interpreted through Fries. Fries’s role in neo-Kantianism was threefold. First, he founded the psychological interpretation of Kant, treating the Critique of Pure Reason as an empirical analysis of the mind’s activities. This psychologistic reading dominated for decades, influencing thinkers from Beneke to Helmholtz, until it was displaced by the Marburg School’s anti-psychologism in the 1870s. Second, Fries was the first representative of the scientific wing of neo-Kantianism, which rejected speculative metaphysics and stressed the methodological importance of mathematics. Long before Trendelenburg or Cohen, he saw critical philosophy as the aide-de-camp of science, its task being to explicate scientific method rather than to compete with it. Third, Fries pioneered the anthropological reading of transcendental idealism, locating the conditions of knowledge in human nature rather than in abstract reason. His influence therefore spans psychology, science, and anthropology. His psychological reading became crucial when Cohen’s Kant’s Theory of Experience challenged it; his scientific interpretation inspired the two Friesian schools; and his anthropological stance fuelled debates with the Marburgers about whether Kant’s philosophy was grounded in reason or in human finitude. Every Kant scholar since has had to navigate between these two poles, the Marburg rationalist and the Friesian anthropological. Fries’s own formation explains this trajectory. Educated in a Moravian seminary, he received a thorough training in the Bible, languages, and the natural sciences, but philosophy was censored. Forbidden to read Kant, he smuggled in sheets of the Critique of Pure Reason, which became for him an act of liberation. Kant represented freedom of thought against religious orthodoxy. Yet Fries approached Kant critically. He admired the Prolegomena and the Prize Essay for their analytic method, beginning with experience and regressing to its conditions, but he distrusted Reinhold’s synthetic derivations from first principles. For Fries, Kant’s true method was analytic rather than deductive. The idealists, beginning with Reinhold and Fichte, had betrayed Kant by turning critique into system. Fries’s lifelong task was to restore the analytic method and to ground critical philosophy in empirical psychology. This propädeutik, or preparatory science, was meant to analyse the mind’s activities inductively, beginning from inner experience and ascending to the general laws of cognition. Such a psychology would not justify transcendental principles but would discover and classify them. Fries insisted on distinguishing between the order of discovery and the order of justification, between subjective and objective method. The first is analytic and regressive, the second synthetic and deductive. His critics accused him of confusing empirical and transcendental knowledge, but Fries believed they misunderstood him. He argued that we can have empirical knowledge of transcendental principles without deriving them from experience. We know them psychologically as necessary features of our nature, though their logical necessity cannot be proved. This circularity, he maintained, is harmless, for transcendental principles make experience possible, including the experience through which we discover them. For Fries, philosophy begins in psychology but does not end there. Psychology provides the materials, not the proofs, for transcendental reflection. Its method is analytic and empirical, yet its subject, the mind, contains the a priori conditions of knowledge. Kant had located these conditions in the structure of reason, whereas Fries located them in human nature itself. Fries wants medicine to grow by sticking to what experience shows. Observe, correlate, and treat. Do not glue grand philosophical schemes or neat mathematical forms onto messy cases. Such schemes are wobbly, and they fit anything and nothing. He draws a hard line between two levels of theory. One level is philosophical and mathematical, a priori and very general. The other is empirical, packed with detail. Do not force the first onto the second. General necessities do not fix particular facts. In practice, only observation and shrewd heuristics guide us. Philosophers blur this all the time, turning matters of fact into matters of first principles. Schelling is the worst offender. He applies metaphysics where we need evidence, thinks a wide concept counts as knowledge, and then carries it straight into the clinic. That is not only sloppy, it is dangerous. A doctor who trusts principles more than patients presumes to know what must work, and the patient pays for the mistake. Fries even hints at a recent tragedy in Jena to make the point. His positive programme is simple. Watch closely, strip away what you cannot yet explain, track the most general relations, measure what you can, and avoid loose qualitative talk. Aim at quantitative relations between variables, but keep mathematics out of first contact with the case. On this basis, Fries praises John Brown’s physiology. Brown starts from observations, not armchair constructions. What Smith did for politics and Lavoisier for chemistry, Brown did for medicine. Schelling liked Brown too, but tried to recast him in a priori terms. Fries pulls Brown back to earth. The core Brownian idea is excitability, the power of an organism to respond to stimuli. Life is the capacity to be stirred and to answer. Each person has a native stock of excitability and a proper balance between receptivity and response. Health is that balance. Illness is deviation, either not enough stimulus or too much. Treatment adjusts the stimulus to restore the norm. The outlines are crude, but they keep theory behind observation, and that is the point. The skirmish with Schelling here is the prelude to a wider attack. Soon after, Fries published his first book, the critique of Reinhold, Fichte, and Schelling. It launched the neo-Kantian counter-offensive against speculative idealism and called, again and again, for a return to Kant’s critical art of philosophising. The book is more than a polemic. It is a treatise on method. Fries’s main charge is that his opponents use the wrong method and then expect the right results to fall out of it. He argues that Fichte only refits Reinhold’s plan. Start from a single self-evident principle and derive the whole of philosophy. Whether the axiom is Reinhold’s consciousness thesis, Fichte’s immediate self-awareness, or the formula “I = I,” the logic stalls. One premise cannot generate a system. You need at least two, and then more again for further steps, which means you must smuggle in fresh assumptions. Worse, a long deduction does not certify the axiom it starts from. Claims of self-evidence do not help, since even knowledge of self is not bare and immediate but bound up with experience of a world. Fichte, Fries says, never separates a psychology of mental laws from a logical system of philosophy, and ends with a hybrid that does justice to neither. Schelling fares no better on method. He reduces phenomena to a few forces through a priori construction, then glosses the world in high abstractions. The first principle is absolute identity, but you cannot squeeze time, difference and finitude out of the pure identity of the absolute. In practice the system names rather than explains. Fries admires the reach of the organic idea, but he insists the method is wrong. His diagnosis is blunt. Since Kant, reason has tried to shake off critique and revive dogmatic rationalism. The cure is to put method first. Begin with analysis, not synthesis. Start from ordinary experience, work back to its conditions, and only then ascend to first principles. Do not confuse critique, which discovers conditions, with system, which displays order. Kant himself, Fries admits, blurred the point by not marking the different methods clearly enough. Reinhold, Fichte and Schelling then assumed that because the conditions are a priori, the way to know them must be a priori too. That mistake is the root of their relapse. Fries sets the critical stance on three pillars. First, the analytic method of discovery. Second, the strict dualism of form and content, understanding and sensibility. Reason supplies form, sense supplies matter. Neither can do the other’s job. This marks our finitude and blocks the fantasy that we create our world by thought alone. Third, system is only a regulative ideal. It guides inquiry but is never complete, since analysis has no natural stop. This book, forgotten by later schools that dismissed Fries as a psychologiser, already sketches the later neo-Kantian attack on rationalism. The only element missing is the shift of target from Fichte and Schelling to Hegel, who at that time was still a minor figure. In the same hungry years in Jena, Fries set out his political thought. He builds on Kant but is willing to break with him. Right belongs within ethics. Moral law rules politics, even though statesmen must work out how to apply it. The key split is between duties of virtue, which concern inner character, and duties of right, which govern outward conduct toward others. The romantics wanted love and friendship to bind the state. Fries rejects that hope. Politics needs law, not warm feeling. He keeps the Kantian distinction between morality and nature, and links it to a second divide between morality and history. What ought to be does not bind what is, unless we make it so. He then separates a pure doctrine of right, which states what should hold, from positive right, which states what does hold. Pure right asks two things, what is right, and how to realise it. The first is for legislation, the second for politics. Politics is the theory of means to moral ends. Here Fries follows Kant’s formula of humanity. Every person has absolute worth and must be treated as an end. Hence the law of right is equality of persons. Equality is fundamental. Freedom and independence follow from it. Now the breaks with Kant. First, right and coercion do not belong together. Coercion is a fact of nature, not a norm of right. Second, freedom is not an original right but a precondition of any right. Rights arise from duties, not from permissions. If you make freedom the basic right, you license anything. Fries even reports an epiphany. Replace the universal law test with the end-in-itself formula. The former is thin and empty, the latter gives content. He does not yet show why reason commands this, but the shift drives the rest of his scheme. He models the structure of the doctrine on the practical syllogism. A major premise states the moral principle. A minor premise states the conditions of its realisation. The conclusion gives concrete laws. He applies the same pattern to politics and to positive right. The point is to keep politics under reason’s rule. From the ideal and its conditions Fries draws laws of application. People must recognise one another as rational beings. They need property enough to live and a common language to make intentions public. From there he deduces, first, that promises must be kept. Second, that property should be distributed by a principle of equality. Third, that there must be a civil constitution under public laws and courts. Fourth, that the… Fries wants a public code of law anchored by two pillars, the sanctity of contracts and the equal distribution of property. He adds a penal code grounded in retribution. He breaks with Kant again. Truthfulness is not only a virtue, it is a legal duty because the kingdom of ends needs binding promises to exist. Part two turns to politics. The problem is force. How do we make right effective. Call the enforced order a republic in the old sense, any public commonwealth. Its form can be monarchy, aristocracy or democracy. Method is empirical. Let history decide what suits a people. Whatever the form, sovereignty must be one. Divide powers on paper and you breed stalemate. The sovereign must make, judge and execute the law. Kant had called that despotism. Fries says it is coherent government. There is no contract with the ruler. Citizens contract with one another to form civil society, not with the state. Hence no accountability claim against the sovereign and no right to revolt. Uprisings are questions of might, not right. This sounds absolutist. Fries counters with one check, public opinion. The people do not legislate but they restrain by judgement. Vox populi binds because it is the living general will, formed historically and contingently, closer to a Volksgeist than to a written covenant. The state has three aims. Distribute property according to equality. Promote material welfare. Cultivate national education. Only the first is a matter of right. The other two are prudential. Policy should be minimal. Each person knows his own good better than officials do. The state is a watchman, not a tutor, and churches are the worst tutors of all. Property is the raison d’être, yet equality is the headline duty. Do not mistake this for socialism. Fries rejects communal property and closed corporate orders. Equal distribution means two things. Sufficient provision for basic needs so that people can be content. Enjoyment of the fruits of one’s labour so that no one works for another’s profit. He offers few instruments beyond poorhouses, since his liberalism mistrusts economic intervention. His republic is not classless. He sketches estates by function, mind and body, intellects and trades and labour. He demands mobility and mingling but assumes most workers will be content if wages are secure and others think for them. He is very specific for his own estate. Protect intellectual property. Ideas are commodities and authors must be able to live from their work. Later, the principle of equality hardens. Equal worth mutates into ethnic sameness. Language, religion and origin become the tests. The slide ends in anti-Semitism, an indelible stain. On religion he writes out of hunger and urgency. He had shed orthodoxy early, doubting revelation, miracles and atonement, yet never doubting God or immortality. Deist, pietist, romantic, and none of these completely. Kant matters in two ways. He teaches distrust of proofs and he furnishes the dualisms that let Fries reconcile reason with faith. Shelling and Hegel threaten both lessons with intellectual intuition and an organic nature that washes away the boundary of appearance and thing in itself. Fries answers by restoring the line. Knowledge is bounded by possible experience. Faith concerns what cannot be given in sense. No intellectual intuition, no theoretical or practical proof of God, freedom or immortality. He rejects Kant’s practical postulates. A good will needs no bribe of happiness and the highest good framed as happiness wed to virtue belongs only to the finite. Reframe the highest good as the kingdom of ends, the eternal order in which all are autonomous lawgivers and all are treated as ends. Think God as sovereign of that order. His distinctive move is a third stance beyond knowledge and faith, Ahnung, presentiment. A feeling that recognises the infinite in the finite. Neither concept nor proof, yet cognitive in its own way. It resists system and remains a mystery in any concrete case. Its locus is aesthetic. The beautiful and the sublime disclose a purposive whole, a world that hangs together like a work of art. Religion is therefore a disposition, not a theorem and not an ethic. It is devotion, a receptive stance. Here Fries meets Schleiermacher by another name. The book fuses Kantian dualism with romantic feeling and pleases neither camp entirely, which is a measure of its originality. At Heidelberg he finally has a chair, not fellowship. He turns inward and finishes the New Critique of Reason. The content is familiar and Kantian. What is new is the method. How are synthetic a priori judgements possible. Not by proof from higher axioms and not by mathematical construction and not by empirical derivation. Past attempts share one error. They equate justification with demonstration. Fries keeps the principle of sufficient reason but breaks the prejudice. Justification must end somewhere, with what is immediately certain for us. He draws the needed distinctions. Proof is syllogistic. Demonstration exhibits content in intuition. Deduction, properly so called, shows the role a principle plays in our basic cognitive economy. Hence two kinds of standing. Transcendental truth would be correspondence with things in themselves. Empirical truth is fit within our web of cognition. Deduction can never give the first. It can give the second. It shows that without some principle we could not so much as perceive or think in the ways we do. This is a functional story about natural necessity, not a logical derivation. It justifies pragmatically by showing necessity and efficiency within the mind’s structure. To reach that structure we cannot prove it into view. We reconstruct it. Reflection, a reproductive faculty, makes explicit the spontaneous activity of reason that works below consciousness. In doing so, the transcendental philosopher does not legislate. He discovers. The aim is a theory of reason. This confusion between epistemic and ontological order becomes, for Herbart, the original sin of speculative idealism. If the act of self-consciousness provides the ground for knowing, it does not therefore provide the ground for being. Knowledge depends on conceptual relations, existence on causal ones, and there is no necessary bridge between the two. Herbart takes this as the decisive point where the idealists overstep the limits of critique and relapse into a form of dogmatic metaphysics. The attempt to derive being from thought is, for him, a reversion to the pre-critical rationalism that Kant had sought to overcome. From this point on, Herbart’s project becomes one of rescuing transcendental philosophy from its post-Kantian distortions. The foundation of philosophy must be critical, not speculative. He agrees with Kant that we cannot begin with things as they are in themselves, but only with what appears to us in experience, yet he insists that this appearance must be treated conceptually, not dialectically. He thus retains the transcendental idealist framework while stripping it of all metaphysical pretensions. This act of intellectual austerity, as he saw it, was the proper way to continue the Kantian revolution in a new scientific age. When Herbart turns to psychology, he does so in a spirit continuous with this critical restraint. Psychology for him is not the empirical study of sensations and feelings, but a rational investigation of the formal conditions under which representations interact and combine in the mind. Its role is to supplement, not to supplant, metaphysics. Where the idealists had turned psychology into a metaphysics of spirit, Herbart insists on keeping the boundary between the two. The mind becomes a field of forces governed by lawful relations, not a creative absolute. His so-called “mechanical” psychology therefore follows from his transcendental commitments rather than contradicting them. This return to lawful regularity marks his departure from the speculative voluntarism of Fichte and the organic holism of Schelling. Freedom, for Herbart, is not the self-positing of an infinite ego, but the moral autonomy of a finite being governed by necessary ideas. The ethical life is shaped by the aesthetic harmony among these ideas, not by their absorption into a cosmic unity. Thus, in a striking inversion of the romantic spirit, Herbart grounds ethics in aesthetics, because aesthetic judgment, in his view, gives the clearest model of how harmony can exist within limitation. It exemplifies the reconciliation of necessity and value without abolishing the distinction between them. What emerges from these revisions is a philosophical stance both critical and conservative. Herbart seeks not to enlarge the Kantian system through speculative synthesis, but to consolidate it through analytical discipline. He restores the separation of knowledge from being, of norm from nature, and of philosophy from theology. In this sense he is more faithful to the letter of Kant’s critique than many who claimed to continue its spirit. Yet the price of this fidelity is a narrowing of philosophical ambition: where the idealists had aimed to comprehend the whole, Herbart contents himself with the conceptual possibility of experience. His metaphysics becomes a kind of grammar for thought, defining what can be conceived without contradiction rather than what must exist in reality. Seen in this light, Herbart’s realism is not a retreat from transcendental idealism but its completion. By affirming the independence of the real from the act of thought, he secures the very boundary that makes critical philosophy possible. The real is not an object known directly, nor an absolute substance, but the logical correlate of experience, posited to explain the persistence of representation. It is an inference required by the stability of consciousness, not a metaphysical posit. This minimal realism is therefore compatible with the most rigorous idealism, for it remains confined within the limits of possible experience while acknowledging the necessity of what lies beyond it. As Herbart aged, this vision hardened into a moral posture. To be a Kantian in 1828 meant to resist the seductions of speculative reason, to guard the frontier between critique and metaphysics. In this he saw himself as the last defender of a fragile inheritance. If the romantics had turned philosophy into poetry and religion, Herbart would turn it back into science. His lectures in Königsberg, delivered from the very pulpit once used by Kant, were acts of continuity rather than innovation, gestures of fidelity in an era intoxicated by synthesis. His students found him austere and meticulous, but to Herbart this sobriety was a virtue: it preserved philosophy from the fever of speculation and restored it to the discipline of reason. Thus, by the time of his later writings, Herbart could justly claim the title he had once announced with pride: “Der Verfasser ist Kanter.” His philosophy was not a new beginning but a recovery, a re-articulation of the limits within which thought must remain if it is to remain rational. Through this effort to wrest transcendental philosophy from the excesses of its successors, Herbart ensured that the critical spirit would survive into the modern age, even as its romantic grandeur faded. For Herbart, the ego and reality are not the same thing. Absolute being is pure stillness, like a flat sea. Do not ruffle it with even the smallest ripple. The ego is the opposite, a vortex pushing outward and pulling inward. Stillness would kill the ego, activity is the ego’s only way of being. He sees another glaring flaw in Schelling. It is dogma dressed as critique. Schelling scolds old metaphysics for overreaching beyond possible experience, then does the same, since his absolute ego, the supposed condition of all empirical consciousness, is not itself within empirical consciousness. Think hard about that absolute ego and you realise it sits beyond all finite experience. It looks very much like Spinoza’s single infinite substance, which is the ground of every dogmatic system. Herbart does not name Kant in those early essays, but Kantian themes run through them. The traps Kant exposed in the dogmatic metaphysics of the 1760s, Herbart now finds in the speculative idealism of the 1790s. Fichte and Schelling, for all their critical posture, slide back into the old errors of Leibniz and Wolff. Again and again Herbart applies Kant’s lessons. Stay within the limits of possible experience. Do not turn a priori forms into things. Admit that humans do not have intellectual intuition. Almost at the same time as Fries, and already in Jena, Herbart saw the cracks in speculative idealism and its first principle programme. He reacted differently from Fries. Fries thought the problems were fatal, so he rejected Fichte’s system and the programme. Herbart thought they showed the need for revision and a better base. He did not know yet what that base was. He would search for it for years. Gratitude to a teacher and patron also slowed the break. Only after a long inner fight did he free himself from Fichte’s pull. The key episodes of that struggle come next. The young men of the Society of Free Men saw themselves as the vanguard of a new order, just as Fichte had imagined. Their aim was to push society toward liberty and equality. The role of the Fichtean intellectual was to explain those ideals to the people and show how to realise them. Revolution was not the route. Reform through education was. Only a prepared public would understand and act. Many of the freemen therefore chose to become private tutors. That let them live their ideals and pay their bills. Switzerland looked ideal, the country of Jean Jacques Rousseau and Johann Heinrich Pestalozzi. By 1797 a clutch of them had gone to the Helvetic Republic, including Herbart, who rode in a small caravan to Bern in March. The night before they left, Fichte and his wife received them. The students expected a party. They got restraint and sour punch. Given that there had been a bash already, that the guests came at midnight and left at four in the morning, we can forgive the mood. At the end, Fichte did grow emotional as his students left. In Bern, Herbart had a contract to tutor the three children of C. F. von Steiger, governor of Interlaken. Hegel had held the job before him. Hegel’s stint had been tense. Herbart’s went well. He won the father’s trust and the children’s affection and kept time for study. The major event of these Swiss years, 1796 to 1800, was his encounter with Pestalozzi, who became the strongest influence on his educational thought. They visited one another in Bern and Burgdorf. Pestalozzi stressed the child’s natural growth and independence and learning by experience rather than abstract lessons. This suited the freemen’s aim of forming autonomous persons. Out went drilling, a narrow focus on languages, and harsh discipline. In came the awakening of the senses so that the child discovers for itself. Fired by Pestalozzi, Herbart devoted much of his life to educational theory and practice and became the leading advocate of Pestalozzian ideas in Germany. He did not give up philosophy. Two short fragments survive from Bern, both from 1798. The first offers plain advice. Think for yourself, avoid cherry picking and reliance on authority, follow a line of thought all the way, do not let pet notions derail you. The second returns to a Fichtean theme, the unity of apperception, and asks how one self can persist across many perceptions. Here he still works within a Fichtean frame, invoking an infinite striving to solve synthetic unity. The later claim that he formed his mature system in Switzerland comes from Herbart himself, who in 1798 wrote that he had found a starting point and that his thoughts contained seeds of many others. A letter from October 1798 shows he was not ready to write a system and was only gathering materials. A friendly rumour that he had one forced him to say plainly that he did not. He had only provisional ideas that he did not yet rate as worth explaining. The Swiss years were a time of consolidation, not yet a turn. One important shift did happen. His stance toward Fichte hardened. He wrote that Fichte’s fairy palace was no longer livable. A quarrel in early 1799 over Fichte’s latest book pushed the relationship to breaking point. The strongest force on his development was not Pestalozzi, nor Fichte, nor Kant, but his mother, Luise Margarethe Herbart. She ran his education from infancy, followed him to Jena, mixed with his circle, and even made Fichte her confidant in her marital despair. She approved his Swiss tutorship but not a long stay, least of all his plan to aim for a chair. She wanted him to act as companion to a prince from Oldenburg on a tour of Germany, then take a government post. When persuasion failed, she claimed illness and called him home. He resigned in Bern and returned in early 1800, only to find that she was not ill and had brought him back for her plans and for divorce proceedings. Relations broke. Back in Germany, estranged and without income, he stayed with friends in Bremen and on a nearby estate. Though his nerves and health were frayed, he worked on philosophy, classics, and mathematics. He later called those years work and sorrow. They bore fruit. They mark the start of his intellectual independence. That independence appears first in a short piece from May 1800, a critique of the theory of the will. He now questions Fichte’s central concept, the I. What has the endless talk of the ego achieved, he asks. Nothing. The concept is self defeating. Fichte says the ego is pure subject and object as one, thinking and being as one, yet he admits that the act of thinking and acting cannot itself be grasped in the very act. Herbart’s verdict is blunt. If the being of thinking would be the act of thinking, and that act cannot be thought, then an intelligence would think what cannot be thought. That is nonsense. With that he drops the concept that had needled him since the mid 1790s. A change also shows in popular lectures at the Bremen Museum in 1800 on morality and religion. He draws a strict line. Morality is about action and decision, our capacity to change the world. Religion is about feeling, an awareness of a world that is given and beyond our control. He keeps one Fichtean note, that one must posit oneself not as found but as demanded. Yet he sets limits to moral striving. It must not eat us alive to the point we stop seeing the world. There is no morality for the person at peace, since peace is a matter of feeling and cannot be commanded. This line cuts against Fichte’s ethical idealism, which urged endless striving to bend nature to reason until nature becomes the product of reason alone. Rather than trying to become divine by will, Herbart recommends rest and the discovery of value in nature outside us. His educational writings from Bremen make the same move. Introducing Pestalozzi to German readers, he insists that education must first teach the child to see the world as it is. Do not overheat imagination or drill the intellect until responsiveness to reality dies. Before we fantasise about another world, and even before we talk about this one, we must learn to see. He calls this power intuition, the capacity to perceive accurately what is given. The aim of education is the cultivation of aesthetic perception. Only then do we gain subtle feeling, a wider field of view, richer imagination, and deeper insight. Seeing is an art that needs exercises. The child’s powers can be grouped as desire, imagination, and observation. Give the most weight to observation, which reins in desire and guides imagination by showing how things are and why they must be so. This ideal cultivates a very different side of human nature from Fichte’s titanic will. It fosters aesthetic perception that recognises limits and necessity within things. Instead of making nature obey us, we learn that it has its own order and value. In this way Herbart develops the religious side of our nature, our capacity for feeling, rather than our capacity for action. The turn away from ethical idealism fits the time. Around 1800 the Jena Romantics and Herbart’s Swiss friends were moving toward an organic naturalism. Nature stopped being the non ego and became an organic whole, a living being with its own laws. The ego became one being within nature, a product and expression of those laws. The whole looked like a work of art and called for an intuitive, aesthetic grasp. Herbart’s Bremen writings show him edging into that stream. Sometimes he went further than the edge. In a striking essay that he added to the second edition of Pestalozzi’s ABC of Intuition he embraces two Romantic themes, the primacy of the aesthetic and organic naturalism. Defending the claim that education should cultivate aesthetic sensibility, he faces the challenge. What about morality. Education must form character. Yet aesthetic training looks only loosely connected to morality. His answer is bold. Morality, rightly seen, is an aesthetic capacity. Moral judgement sits under aesthetic judgement. He argues that morality is fundamentally about obedience, the acceptance of an obligation that binds the will. The source of obligation is not in the will, since the will is bound by the law and cannot change it. It is not in theoretical reason, since theory tells us what must be, while obligation binds with an ought. The source must be aesthetic, a capacity to perceive proper relations and to judge worth. He calls this a function of reason, but a reason that perceives and judges rather than merely infers. Organic naturalism shows when he questions freedom of the will in the latest moral system, which everyone would have taken as a nod to Fichte. If education aims to foster morality, the concept undermines the aim. Freedom, as a purely intellectual power independent of the sensible world, would be out of reach for the educator, whose means lie within that world. For the educator, morality is a natural event in the pupil’s mind. He believes he can stimulate and encourage it only because it unfolds under necessity. The advocate of transcendental freedom will say the educator’s influence is just another event, but Herbart is unmoved. Each person, though unique, is a part of nature whose necessity expresses itself through him. By 1802, at the close of the Bremen years, Herbart had moved far from his Fichtean past. He rejected ethical idealism, the concept of the ego, the view of nature, and transcendental freedom. In rejecting them he drew energy from Romanticism. Herbart the Fichtean became, briefly, Herbart the Romantic. Yet there were checks within him, many from Kant. In May 1802 Herbart arrived in Göttingen as tutor to the son of a Hanoverian minister, Count von Grote, and to push toward a university post. He registered for the doctorate and the habilitation, which required public disputations on two consecutive days in October, each with a set of theses. We do not have his arguments, but the theses show a sceptical and critical turn. Against traditional metaphysics, they say it cannot form a complete whole and they doubt the existence of a single first principle. Against practical philosophy, they deny a bodiless natural law and deny there can be a general theory of the ideal state or a theory of punishment. More striking, they hit transcendental philosophy in both Kantian and Fichtean versions. Transcendental freedom is empty, not needed for ethics, and even if it existed we could not know it. The Kantian inference in the transcendental aesthetic is challenged. Fichte’s intellectual intuition is called a nullity. The ego is called self contradictory. These theses show how far he had travelled from his youth. Some say they mark the birth of an independent philosophy set against transcendental philosophy. We need perspective. He would keep criticising those particular doctrines, but he did not throw out transcendental idealism. In the Göttingen years he developed a metaphysics he himself called transcendental idealism. He held that the immediate objects of cognition are representations and that what we know through them are appearances. He passed both exams with distinction. He lectured for the next two years as a private lecturer on metaphysics, introduction to philosophy, and pedagogy, and he built a reputation as an effective teacher with close ties to students. Heidelberg invited him in 1804. Göttingen countered, and he stayed. The Heidelberg chair went to Fries. After promotion, he delivered an inaugural lecture on Plato’s system and the place of the good among the ideas, later published with an appendix. He stresses the relevance of classical philosophy for modern thought and warns that modern systems often mix Heraclitus, Parmenides, and Plato in incoherent blends. He adds that Fichtean idealism is a prime offender. The lecture is a parable against current errors. On his reading, Plato sought the object of knowledge in what does not depend on relations. This led him to the ideas. The sensible world, because of change and contradiction, lacks true being and is illusion. Herbart’s stance is Kantian. He rejects that idealism and wants to save the reality of experience by dissolving supposed contradictions. He announces a method of relations, or a doctrine of completing concepts, but explains it fully only elsewhere. There he says philosophy tends to isolate concepts from their natural connections and to treat them as unconditioned. Contradictions then appear. These are a prompt to restore the lost context. The task is to show the necessary connections between concepts and so remove contradictions. A short plan for lectures in 1804 adds a programmatic note. Philosophy is the activity of thinking about ultimate questions more than a fixed system. Its method is whatever habits of thought prove useful. The best teaching is to spark independent thinking, not to impose a system. He salutes the power of the Kantian revolution and notes that leading minds have not moved far beyond it. He also warns against a Romantic misreading of his aesthetic account of moral judgement. It should not be confused with big talk about the beautiful as the highest. The picture is of a young thinker who will not be boxed in by a system, a free spirit who has cleared the ground and is ready to build. In 1806 he published Main Points of Metaphysics, a breakthrough that laid the base for his philosophy and largely underwrote his 1828 General Metaphysics. The work is brief and dense, written for prepared auditors, and its obscurity has bred conflicting readings. Its Kantian frame is clear. Metaphysics is the science of the conceivability of experience, not knowledge of the absolute. Its task is to show how central concepts of experience are possible by exhibiting their relations to other concepts. The method is the method of relations. Against the followers of Schelling he insists, in a Kantian spirit, that cognition is not a mirror of things in themselves and that claims to intellectual intuition are dogma. He cites the warning that even the holy gospel must be measured against moral perfection before it is recognised as such. He begins with method. He states a classic problem. What connects a ground to its consequent. If they are the same, the inference is empty. If they differ, there is no necessity. For Herbart this is another face of the problem of synthetic unity. He treats it now as a logical issue. We solve it by positing a middle concept that mediates, a whole with distinct parts or aspects. The whole connects by being in both, and distinguishes by being in them in different ways. The method then determines, case by case, the respects of identity and the respects of difference. Since each part is itself a whole, the same problem recurs inside it, and the analysis must continue as contradictions reappear at deeper levels. Herbart sets no fixed end to how far this analysis can go. The point of the method of relations is transcendental. It is meant to show how a synthetic a priori concept is even possible. Such concepts are the necessary conditions of experience. They shape how we take in and organise the world. The method works by locating and removing the contradictions that appear when we use these concepts. It does this by showing that each concept is a coherent whole, a unity that is synthetic because some of its elements are the same in certain respects and different in others. That can sound a lot like Hegel’s dialectic, which was being forged at about the same time. Structurally there are likenesses. Both procedures surface a tension, analyse it, and seek a higher order resolution. The purposes are opposed. Herbart’s method exists to protect the possibility and reality of ordinary experience, to stop philosophers declaring the world an illusion on the back of a too tidy theory. Hegel’s procedure aims to show that the merely finite is empty on its own and has reality only as an appearance of the Idea. With method on the table, Herbart moves into metaphysics proper. He calls this a transcendental inquiry. It treats the most abstract building blocks of metaphysics, such as being, essence, force, substance and change. The presentation is extremely condensed. Rather than summarise the whole sequence, it is best to bring into view the parts that matter for his version of transcendental idealism. He starts with being. A standing warning accompanies the analysis. The thinker never steps outside the circle of his own representations. We can therefore speak of being only as a thought we attach to a subject. The thought in question is the bare act of positing. To say that a is means only that a is posited. Being is sheer existence, nothing more. From this it follows that existence is not a predicate. It adds no content. A thing does not relate to others by virtue of its existence, since relations travel through properties. Being as such is self sufficient and simple. It is not explainable, because explaining means showing connections to other things. Next comes essence (Wesen). Whatever we think as a being is a being of this or that sort. Essence is this thought of a thing’s being. But because being excludes relation, essence in this sense is one. Not one item among many, but one in the sense that it bears no plurality at all. It has no degree, quantity or infinity, all of which presume relations. When Herbart speaks in the singular of a being he is speaking loosely. Strictly, if we attend only to sheer being, there is nothing that forces a plurality. In so far as things are, they are the same, because in so far as they are we consider essence alone. If there is multiplicity it must arise from somewhere other than bare existence. This threatens to make being ineffable. We do, however, talk about being. What then is the status of that talk. Herbart bites the bullet. Our discourse uses images (Bilder) that must not be confused with what they image. They are how being appears to us. They are accidental views (Zufallsansichten) of being, not being itself. He now turns from abstractions to experience. We never encounter simple sensations in isolation. They appear together in complexes that we call things or substances. At once a problem appears. We take a thing as a unity, the whole of its properties. But the properties are irreducibly different. Each points to a simple and unique kind of sensation. No one can form a single sensation that is at once the yellowness and the heaviness of gold. So the form of the thing, which posits one, sits at cross purposes with the matter of the thing, which gives many. The one being and the many beings somehow have to be the same. From here Herbart draws a first major conclusion. We cannot know things in themselves. Earlier he had made being itself unknowable. That by itself does not imply that particular things are unknowable. The added step rests on a contrast he keeps drawing. The thing is one. Its properties are many. The thing is unique. Its properties bring it under classes. The thing is indivisible. Its properties divide it into aspects. The core thought is this. The essence of the thing is propertyless. All knowing goes by way of properties. If knowing a thing means saying what it is, and if saying what it is always attributes some property, then the essence of the thing is not the sort of item we can know. He draws a second conclusion that vindicates the critical philosophy. Empiricism and rationalism are both needed and each corrects the other. Rationalism is right that we must posit a single thing beyond the senses. Empiricism is right that the properties we ascribe must be given in experience. Taken together they capture the shape of our situation. He introduces change. If we identify a thing with the conjunction of its properties, then any change in any property produces a numerically new thing. Identity would flicker at every moment. We avoid that by positing identity through change. We say the thing can gain and lose properties yet remain the same. Now we are both identifying the thing with its properties and distinguishing it from them. The contradiction lies in plain sight. One substance ought to be many, and many ought to be one. Herbart does not offer a resolution here. He presses the tension by shifting to force (Kraft). Force seems promising because it lets us say the many properties are manifestations of one underlying power. Yet this too breeds trouble. On the one hand, a property has its determinate quality by not being another property. Pure contrast sets them apart. On the other hand, each quality is a simple positive what, self standing, indifferent to others. Neither route gives us unity. The first scatters the qualities into mutual exclusions. The second lines up insulated simples. At this point he ascribes to each being an act of self preservation (Selbsterhaltung). He explains little in the moment, but the thought follows. If we have already spoken of force to save unity, and if we insist on identity through time, it is natural to think of a power that maintains identity. If there is such a power there must also be disturbances (Störungen) that press against it. Disturbance does not annul inner identity. Self preservation keeps the thing in being. This pair will matter later when he turns to psychology. After substance, change and force he treats space, time, motion and causality. Here he makes his distance from the Kantian Transcendental Aesthetic explicit. In his introduction he had already objected that calling space a form of intuition does not tell us how we get specific shapes. That complaint stands. He refuses absolute space and absolute time. Space is constructed from places that bodies occupy. Space follows the relations between places. The idea of an absolute container that precedes all such constructions is a mere abstraction. Absolute time falls under the same criticism. Time is nothing over and above the form in which something goes through space, that is succession. In his words, time is the quantity of succession divided by speed. As with the earlier concepts, he generates contradictions in the notions of absolute space, time and motion, drawing on Zeno when it helps. He repeatedly uses the method of relations to diagnose why the contradictions arise. He does not, in these pages, resolve them. A cryptic note at the end of section nine clarifies the aim. The doctrines of the nothingness of space, time and motion, and the unknowability of things in themselves, belong to a realistic metaphysics. All these depend on positing a real something that experience seems to indicate. This realism, he says, is the inevitable booty of idealism. Idealism that cannot be refuted from the outside breaks down from within, under its own contradictions. This is not a rejection of Kant. On the contrary, Herbart is deploying the Kantian point that the antinomies spring from transcendental realism and are healed by transcendental idealism. The idealism that collapses is not Kant’s, but the sort that the Prolegomena attacks, which declares space, time and experience to be mere seeming. Herbart even complains about the confusions produced by Kant’s use of the label idealism, since Herbart wants that term for his own transcendental position. Section ten, titled Idealism, brings the position into focus. There are two realms. There is a realm of appearance (Schein) and a realm of being, which is that of intelligible nature. The two are sharply separate. Even though the realm of being appears through the form of appearance, it does not explain any particular in that realm. There must, however, be something that bears appearance, a representing being. The line between noumenon and phenomenon hints strongly that the contradictions we meet in experience are to be dissolved by the familiar Kantian strategy from the dynamical antinomies. Let the thesis speak of things in themselves and the antithesis of appearances. Herbart does not say this outright, but it fits his general appeal to the appearances and things in themselves distinction, and his insistence that we use the method of relations to unwind the knots. The outcome is a recognisably Kantian transcendental idealism. He adopts the central distinction between things in themselves and appearances and claims knowledge only of appearances. He reaches these conclusions without relying on the Transcendental Aesthetic. He gets there by analysing being, substance, change and power and by driving the antinomies into the very heart of experience. Even so his idealism is more realist in flavour. He stresses the givenness and stubborn particularity of sensible qualities. My consciousness is not a self contained realm, because it arises through interaction with other beings that disturb my pure activity. In this spirit he speaks of his own strict realism (strenger Realismus). The appearances of representing beings arise from the colourful mixture of disturbances that occur in their interaction. So it is not wrong to call Herbart a realist. One simply has to place that realism inside his overall transcendental idealism. During these Göttingen years Herbart was prolific. In 1806 he published the Metaphysical Main Points and, alongside it, the General Pedagogy, a systematic statement of his educational views. Soon after he issued On the Study of Philosophy. In style and audience this is the opposite of the earlier compressed book. It is clear, direct and written for beginners. Its aim is to teach the goals and methods of philosophy. Here he defines his conception of philosophy and, without saying so on every page, he sets it against Fichte and Schelling, and aligns it with Kant. Philosophy should not lay down the first principles of all knowledge or serve as the foundation of every science. It should not begin from an esoteric intellectual intuition. It should begin from the logic of our ordinary concepts and from the principles actually used in the special sciences. This is not an endorsement of the status quo. Philosophers must subject those concepts and principles to criticism, because some of them, like being, activity, cause and continuity, seed paradoxes. Empiricism tries to dodge the puzzles by pretending that experience is simple and unproblematic. Rationalism reaches for abstract principles that outstrip experience. Neither approach succeeds on its own. Real progress uses abstraction but stays answerable to experience. He treats philosophy as a problem solving enterprise. Identify the problem correctly. See all its factors. Grasp the requirements that any solution must meet. The right method is the willingness to let the problem set the path. He still values systematic unity, but warns against premature system building, which forces the data into a mold and brings inquiry to a stop. Advance toward unity only where the work can correct itself. Like Fries, he recommends an analytic method. Begin with the bethos of experience, that is, with the concrete intuitions and the ordinary concepts. Immerse yourself in the subject matter. After that ordeal, form a basic concept, a guiding idea that articulates what you have seen and can anchor the investigation. Explore its logic, but repeatedly test its implications back against experience. Intuition is allowed at the start, but it is a starting point that demands later critical work. There is no privileged first principle to be certified by intellectual intuition. Different philosophers will have different starting points. That variety is an asset. The best system will bring together the partial standpoints and basic concepts that, taken together, form the truth. The book is also a polemic against the a priori methods of Fichte and Schelling. He rejects appeals to intellectual intuition as a means of grounding a system. He refuses the habit of imposing a schemata on facts. He will not begin from the Absolute or the Ego, because such starting points are not drawn from experience. While he accepts the need for unity, he insists that such unity is for us as knowers, and may have no counterpart in reality itself. He draws a line between the order of knowing and the order of being, as he had already done in his critique of Schelling. Philosophy differs from other disciplines because it is second order. It investigates our concepts of things, not the things themselves. In the same polemical spirit he rejects a fundamental doctrine of post Kantian idealism, the unity of reason. The aim at unity is central, yet there is a basic dualism that no system can remove. Norm and fact, practice and theory, remain distinct kinds of discourse without a single principle that fuses them. Fichte violates this distinction by making the moral law a condition of possible experience. Schelling violates it by reading teleology into nature. Despite his critique, Herbart does keep one idealist inheritance. He is still a dialectician in method. Fichte’s Science of Knowledge had already used an analysis and synthesis to draw out and resolve contradictions between concepts. Herbart’s method of relations is made in this image. He now explains it as a progressive analysis in which one finds a middle term that links the two sides, and then a middle term for that middle, and so on. He calls this a method of exposition rather than discovery. That is his way of avoiding any grand a priori claim. His General Practical Philosophy of 1808 sets down the base of his ethics just as the earlier book did for his metaphysics. True to his insistence on the divide between the normative and the natural, the practical and the theoretical, he treats metaphysics and ethics as equal and co ordinate. He devotes most of his energy to metaphysics, but this is his one systematic ethical work. It sits oddly with his repeated claim that his deepest ethical debts are to Kant. He denies that there is a single supreme principle. He denies that reason is the source of obligation. He treats obligation as case bound. He grounds morality in aesthetics. Where then is the debt. The answer is that he borrows from Kant’s aesthetics, not from the Groundwork. The introduction states his starting problem. Do we call something good because we desire it, or should we desire it because it is good. He takes the second horn. Values involve desire, but are not set by it. The good must come first or else we would have no way to judge desires. So the basic presupposition of practical philosophy is that there can be a will less valuation. He thinks most current theories spoil this presupposition because they all make the will primary. Theories that begin from the good, from virtue and from duty alike put the will in charge. The will provides the goal, the will is the supreme power behind character, the will is the source of duty. Once you do that there is no way to judge the will itself. This is best read as a criticism of Kant’s autonomy. Kant calls the moral subject bound only to laws it legislates for itself. Herbart worries that a will that makes laws can unmake them. There is then no standing above the will that can call it to account. Kant tries to ward off the danger by requiring universalisation, but Herbart thinks that requirement is too thin. Many imperatives can be made universal. The form by itself puts no real content in the law. If the will cannot regulate itself, there must be a higher authority. He simply declares, without argument in that paragraph, that the authority is aesthetic judgment. Morality should borrow from aesthetics a model of judgment that is independent of the will and that bears authority over it. Aesthetic judgment can find something beautiful or sublime whether or not it is an object of desire. The Kantian provenance is obvious. The third Critique argues that judgments of taste are independent of interest, and that their pleasure arises from contemplation and reflection rather than appetite. Since aesthetic judgment is disinterested, and since interest involves desire, it is independent of the will. This supplies a response to Kant’s own confession in the Groundwork that he could not explain why we should take an interest in the moral law. If the motive cannot come from sensibility and cannot come from pure reason without begging the question, we need a third route. Aesthetic interest sits between the sensible and the rational. The beautiful and the sublime can move us to act morally. Kant himself almost says this when he ties the sublime to the idea of dignity and treats humanity as an end in itself. Having borrowed the scaffolding, Herbart builds his own account. He insists on keeping aesthetic and moral judgment distinct, so that the one does not collapse into the other. He marks two differences. First, the representation of the beautiful or sublime is singular and complete. The representation of the good is general and incomplete. Second, in aesthetic judgment the representation of the object is separate from our attitude of approval or disapproval. In moral judgment the representation and our approval are bound up together. He adds a nuance. In aesthetic judgment we are indifferent to the bare contents, for instance a single sound, but we are not indifferent to the relations between the contents, for instance the harmony of tones. Form is the special object of aesthetic appraisal. He imagines a science of aesthetics that catalogues basic forms and the kinds of pleasure they stir. He then argues that moral judgment depends on moral taste. Taste in general is the capacity to perceive and judge particular forms and relations. Moral taste is not different in kind from poetic, musical or plastic taste. Like them it needs sensitivity to particulars, what Hume called delicacy and Herbart calls tenderness of feeling. Its special focus is desire itself, above all our own inner states and the relations between wills in concrete situations. The standard objection to any aesthetic theory of morals is that it cannot yield the universality we associate with moral judgment. Taste is personal and contradictory. Herbart faces the objection head on and gives a startling reply. We should let go of the demand for a single universal principle. The hope for one law that covers every case is idle. He does not argue this by a direct attack on the categorical imperative, though it is in the background. He argues instead that moral judgment always concerns complex and unique situations. Life is too various for us to know in advance how all simple relations of will will combine. He allows a minimal universalisation. We must avoid contradictions. Different people should judge alike in exactly the same circumstances. Yet once we specify circumstances fully, the law is no longer general. It gives us consistency, not generality. This becomes a strength, not a weakness, because it respects the particularity of action as aesthetic judgment respects the particularity of a work of art. He does not throw away rules altogether. We can still use general guidelines. We form practical ideas by abstracting common features across cases. These ideas are not induced from sensation but arise from what he calls an intellectual intuition, by which he means a direct grasp of a pattern, not the speculative faculty invoked by his post Kantian opponents. The rest of the ethics is an outline of the key practical ideas. That is beyond our present scope. Herbart’s fortunes at Göttingen soured with politics after 1806. The French rule brought financial stress and institutional gloom. He longed to leave and did so when Königsberg called in late 1808. He took Kant’s chair in 1809. The symbolism mattered to him. He told friends that a childhood dream had been fulfilled and that he would count it a duty of the office to preserve the memory of Kant. The identification with Kant sharpened his alienation from the drift of German philosophy under Schelling. He saw two corrupting forces. There was formalism, the habit of imposing a prior schemes on facts. There was mysticism, appeals to intellectual intuition. In 1813 he wrote a polemic on the attractiveness of Schelling’s doctrine. It was pointless, he said, to refute Schelling yet again. Fries and Krug had done that. The question was why the doctrine persisted. The answer was that an appeal to intellectual intuition is popular because it saves hard thinking and because it is unfalsifiable. If the Schellingians took Kant’s call for criticism seriously they would not claim infallible intuitions. Intuition can be a starting point but not an end point. It must be rendered into concepts, judgments and inferences, and these can be criticised. A pamphlet of 1814 takes on what he calls the fashion philosophy of the day. At issue is the definition of philosophy itself. In his textbook he had defined philosophy as the cultivation of concepts. The reviewer objected that philosophy should go straight to reality and not limit itself to our concepts. The reply reveals how much Herbart prefers Kant’s legacy to fashion. If there is to be knowledge for us, we know only through representations. In philosophising we deal immediately only with our representations. To forget this and leap into reality is to fall back into the swamp from which Kant rescued his generation. He then sets out his own credo. All inner and outer intuitions are representations within us. They give us no knowledge of things in themselves. Placed against his opposition to Schelling, the point is clear. Transcendental idealism is critical. It does not presume that our representations reach things in themselves. Absolute idealism is dogmatic. It presumes an immediate grasp of the real through intellectual intuition. Those who label Herbart a realist and who infer from that that he opposes transcendental idealism overlook this declaration. We come at last to psychology, the domain that most strains his relation to Kant. Herbart thinks Kant failed as a psychologist and that philosophy must be rebuilt on a new psychology. Although he always cared about psychological questions, only in Königsberg did he give them full attention. His first systematic text is his Textbook on Psychology of 1816. It launched his attack on faculty psychology and sketched the doctrines that he later developed in his 1824 Psychology as Science. The preface and introduction of the textbook set his view of method and of psychology’s place among the sciences. Psychology is not an independent empirical science. It is part of philosophy. In his classification, it is applied metaphysics alongside physics and physiology. It is the most important of the three for philosophy because it is needed to put the question of how knowledge is possible, and because psychology has served as a weapon against prejudice, even while it is burdened by prejudices of its own. Improving psychology is a basic condition for correcting errors elsewhere in philosophy. Its method should be as close as possible to that of the other empirical sciences. He calls it rational empirics. Derive laws from observation. Use the laws to predict and test further observations. His psychology is intentionally naturalistic. The mind is to be explained under natural law, as part of nature’s fabric. He explicitly denies that this commits him to materialism. Matter is appearance, on his view, so subsumption under law is not the same as reduction to matter. He is not naive about the prospects for pure empiricism. There is no such thing in psychology. There are no raw data untouched by interpretation. Self observation distorts, tears phenomena out of their context and then yields them up to general concepts. Inner experience has no special epistemic privilege over outer experience. It is as hard to know ourselves as it is to know external things. These scruples go beyond the confidence shown by Fries and Beneke. Given such doubts, why think psychology can be a science at all. He sets out guiding assumptions. Mental life consists in particular events. These events are in constant change. They form a manifold within one consciousness. He adds a working hypothesis. Representations are forces, and their activities are measurable. This hypothesis gives psychology its one hope of mathematical treatment. The justification of these assumptions comes from metaphysics. That is where we examine the presuppositions that make empirical psychology possible. So his psychology wears its tentativeness openly. It is an acceptable hypothesis. The chief obstacle is old faculty psychology, which he treats as a relic of scholasticism. The worst move is the slide from what happens in us to powers we possess. Attributing a faculty to a class of similar phenomena is myth making. It resembles populating nature with special gods for rain and harvest. Nor is a faculty like a natural law. The concept is too vague to define fixed operations under fixed conditions. It is a hypostasis, the reification of an abstraction. One faculty theory draws special fire, the tripartite division into representing, desiring and feeling. It finds its classical home in Kant and was widely accepted. Herbart brings many objections. The induction is incomplete. The boundaries are not firm. The same item can fall under several heads. The powers cannot be treated as separable, as if each could function apart. Worst of all, the scheme tears up the indivisible unity of the mind. That unity is his touchstone. He implicitly subordinates epistemology to psychology. He writes that one reason psychology is crucial is because of the psychological question of the possibility of knowledge. He argues that epistemology will approach a proper scientific status only in company with empirical psychology. Here Kant becomes the foil. If the foundations of Kant’s philosophy are to hold, they must also be rational empirics. In Herbart’s judgement, Kant made epistemic mistakes because of faulty psychology. People do not represent space as an infinite quantity by nature. Substance and cause are not universal principles for understanding at every stage of life and culture. There is not, in every person’s moral consciousness, a categorical imperative poised for expression. Since Kant, psychology has moved backwards, not forwards. Leibniz and Locke grounded it better by tying it to experience. Wolff and Kant later spoiled that beginning by turning psychology into scholastic anatomy, driven by a priori methods and the assumption of faculties. Kant made things worse by attacking Wolff where he was most plausible, in conceiving the mind as a substance, and by tightening rather than cutting the web of faculties. The verdict is harsh. The critical weapons were sharpened with care, but they were made of brittle metal. They shattered in use and must be reforged. Part two of the textbook lays out his positive doctrine. The mind consists in acts of self preservation that present themselves as representations. He refuses to begin with the soul, a subject that exists nowhere at no time and is therefore unknowable. He begins with particular acts of self preservation. He does not assume a subject in which they inhere. He does not speculate on their source. He believes he has a metaphysical right to the guiding assumption, because in the Metaphysical Main Points he argued that essence consists in power, and power in acts of self preservation. One hears Leibniz in the background. Each monad strives toward representation. We therefore begin with representations as acts of striving. Representations never exist alone. They stand in relations. From this arises a system of striving and counter striving, action and reaction. He explicitly invokes a physical analogy. Herbart says our ideas press against and push back on one another, like forces in physics. In fact, ideas are forces. They attract and repel. Crucially, an idea does not have power all by itself. That would be turning an abstraction into a thing. It has power only in relation to other ideas, and especially when it meets resistance. Each idea both resists and yields. Without that two way strain it would not be a genuine striving. If ideas are forces, we can treat their strength as a quantity. It shows up to us as clarity or obscurity. That opens the door to measurement, which is what turns psychology into something scientific. Herbart sides with Kant that a field is scientific in proportion as it admits mathematics. He simply denies Kant’s claim that psychology cannot be mathematical. Think of each idea as made up of infinitely many elementary apprehensions, Leibniz’s “petite perceptions” in new dress. When these fuse, they form one total force. Most ideas, like Leibniz’s, are sub conscious. They reach consciousness only when their striving overcomes what holds them back. Once an idea’s strength crosses a threshold, it becomes conscious. There are limits here. No idea is infinitely strong, so he proposes a law of diminishing receptivity. The stronger an idea already is, the less any further increment adds to its strength. Consciousness, on this picture, is simply the sum of all the ideas that are at or above the threshold at the same time. After reducing consciousness to interacting ideas, Herbart seems to bring the soul back in through a side door. He says the unity of the soul grounds the opposition among ideas and makes their system within consciousness possible. He says again that the soul’s unity underwrites the unity of experience. This looks like a leftover from his Kantian and Fichtean youth, and it does not sit neatly with his repeated claim that the laws of interaction among ideas alone generate experiential unity. He anticipates the standard objection that his psychology is too reductive because it treats only quantities and ignores qualities, especially feeling and desire. He replies with a theory of feeling and desire inside representation itself. He uses traditional German terms, but we should translate them clearly. The “soul” is called mind, Geist, so far as it represents. It is called heart or disposition, Gemüt, so far as it feels and desires. Either way, feeling and desire are functions of representation, so they too can be brought under quantitative law. Desire is what we have when an idea is driven forward yet held back, producing displeasure that spurs the will. Feeling is what we have when an idea advances by its own power and is helped along by other forces, which strengthens it. Ironically, this brings him quite close to Christian Wolff’s old thesis that the mind is fundamentally a power of representing, with desire and feeling as aspects of that power. The Kantian tripartite scheme that Herbart had criticised grew out of a critique of Wolff for making everything representation. Herbart’s compressed handling of the Kantian worries here really is too thin. Those are the basics of Herbart’s first pass at psychology. How far can the mathematical part go. In a later essay on the suitability and limits of mathematical psychology he admits that mathematics is useless in metaphysics and that it applies only where there are quantities. The mind is not only qualitative, he says. There is a broad quantitative side that fits measurement. He lists four domains. First, the strength of an idea, measured by its clarity or obscurity. Second, the degree of resistance between ideas. Third, the degree of connection among ideas and how many are connected. Fourth, the length of a series of ideas and the speed of change along the series. He is especially keen on the fact that ideas form different sorts of series, each with its own equations. He then concedes a hard limit. His mathematics cannot touch the content of ideas. What is represented, as such, falls outside the theory, except insofar as it affects resistance and connection. That is a striking retreat, because it hollows out the epistemological ambitions he had promised. Epistemology lives with content, meaning, reference and truth. So although he vowed to rebuild theory of knowledge on psychology, his psychology leaves little of theory of knowledge to support, and least of all Kant’s. Throughout the textbook he rejects one Kantian doctrine after another, always on the grounds that they are bad psychology. He denies that unity of experience is the product of an act of synthesis. Ideas, he says, cohere by their own forces. Unity is given in experience. We introduce distinctions afterwards. He dismisses inner sense as a mere invention and not a very good one, since we know neither its stock of ideas nor its law of operation. He questions the assumption, central to the metaphysical deduction, that all thinking is judging, because thinking does not necessarily involve language. Most strikingly, he rejects the very idea of a faculty of understanding that consists of concepts. In his view there are no concepts in the robust sense. There are only abstractions. What we call concepts are ideals that our thinking aims at and rarely reaches. In short, the entire apparatus of innate powers and activities collapses under his attack on faculties. The mind is not a stock of inborn capacities. It is a web of ideas and their self organised connections. Given how hard he hits Kant’s psychology, and given that Herbart’s psychology became the most influential part of his legacy, it is no surprise that people overlook the Kantian side of his work. It is difficult to square a mechanised, naturalised psychology with a transcendental philosophy. Still, as we have seen, outside psychology Herbart is indeed very Kantian. His transcendental idealism, his critical picture of philosophy, his resetting of ethics using Kant’s aesthetics, and his adherence to Kant’s basic dualisms all justify his public confession in 1833 that he remained a Kantian and would remain one. That remark was not theatre. It summed up convictions hammered out from Jena to Königsberg, and they were already present in the child who pored over the sage of Königsberg. Friedrich Eduard Beneke, often misspelled in older sources, is the last major figure in the German strand of empiricist psychology allied to neo Kantian themes. He was born in 1798, a generation younger than Fries and Herbart, and came of age in the early 1820s, when the wonders of Jena were already fading. While Fries and Herbart were established professors, Beneke was a student in Berlin. What they shared was life under the shadow of Romanticism and speculative idealism, which dominated German philosophy in that decade. All three pushed back. They cast their lot with the empirical and mathematical sciences and took Kant as their emblem. Beneke stood with them on core points. He put empirical psychology at the base of theory of knowledge. He upheld transcendental idealism in its critical core. He reacted against the new rationalism of Fichte, Schelling and Hegel. He called for an empirical, analytic method and swore allegiance to Kant’s critical spirit, which he believed speculative idealism had betrayed. With Herbart he defended a situational ethics and an aesthetic grounding for morals. Beneke knew these affinities. He had read Fries young and said he was formative. He admired Herbart, calling his metaphysics the sharpest and deepest of the century, though he found Herbart only after his own outlook had largely set. He even proposed collaborating. Herbart praised and reviewed him kindly, but treated him as a pupil, not a peer, and drew a firm line where their differences went too deep. To Herbart, Beneke’s radical empiricism looked like a relapse to pre critical days. Herbart also thought psychology needed a metaphysical base, while Beneke insisted it must be entirely empirical and drop metaphysics altogether. Beneke pushed empiricism and psychologism further than either Fries or Herbart. Early on he denied the a priori altogether and said experience alone grounds knowledge. He also treated every intellectual discipline as a branch of psychology, which he made the basic science. For that reason he sits uneasily in many histories of neo Kantianism, and has often been ignored. The neglect is understandable. On the British model he rejects Kant’s rationalist strands, including forms of intuition, the synthetic a priori, the method of deduction and the categorical imperative. After that, how is he still Kantian. Yet he identified himself with Kant, and published one of the first neo Kantian manifestos in 1832. He did so for two reasons. He took transcendental idealism to express the central anthropological truth that knowledge revolves around the human subject. He also saw Kant’s empiricism as the best antidote to speculative excess. For Beneke the beating heart of Kant’s work was its critical, empirical limit setting, which beat back the rationalism of Descartes, Leibniz and Wolff. He meant to continue that battle against the new rationalists. Beneke belongs to the old German anthropological tradition in philosophy. He studied Platner, Locke, Hume, Garve, Tetens and Fries, and he kept their central lesson. All knowing begins in us and must revolve around us. From that it follows for him that psychology is the master science. When Herbart later demanded a defence of this radical programme, Beneke returned to this maxim again and again. Even as he worked, his psychology was going out of date. True to the anthropological school he kept the concepts of soul and self observation. Unlike Herbart he doubted how far mathematics can go in explaining qualitative mental life. By the 1830s, psychology in Leipzig was turning experimental, physiological and mathematical. Fechner, Völkman and Weber were running careful experiments in visual perception, beyond anything Beneke practised or envisioned. Later neo Kantians would align themselves with the new experimental and physiological psychology rather than the older anthropological style. His impact was small. He never had the recognition he deserved. No school formed around him. He had a few students who mainly applied his ideas to pedagogy. Later in the nineteenth century he found a modest place in histories of philosophy, and only recently has he drawn the attention he merits. His life was tragic. He was born in Berlin on 17 February 1798 into a solid civil service family. He excelled in languages and mathematics, loved poetry, and graduated top of his gymnasium at seventeen. He volunteered in 1815 against Napoleon, then studied theology at Halle, learned Hebrew and Arabic, and won prizes for religious essays. There he also caught the philosophy bug from Kantian professors Ludwig Heinrich Jakob and Johann Christian Hoffbauer. He returned to Berlin in 1817, attended theology and philosophy, and listened to Schleiermacher. He had an epiphany on the way to church, not in the sermon. Talking with his brother about the dire state of philosophy and the need to change its course, he resolved to devote himself to reforming it. He was nineteen. He went straight to the dean the next day to qualify as an instructor in philosophy. Just two months later, in August 1820, he filed his inaugural dissertation, On the Ends of Philosophy, announcing his programme and attacking the prevailing method. He began lecturing that winter as a Privatdozent. It was risky to compete in Berlin with Hegel, who enjoyed popularity and state favour. Schopenhauer tried in 1821, scheduling his lectures opposite Hegel’s, and had five students. Beneke prospered. In 1821–22 he had thirty students in each of two courses, one on logic and metaphysics and one on mental illness. That success could only trouble Hegel. In February 1822 the philosophy faculty cancelled Beneke’s next term and withdrew his venia legendi. No reason was given. After Beneke begged for an explanation, the education minister, Altenstein, told him the issue concerned his latest book, the Foundations of Physical Ethics, but could not say how. His secretary, Johannes Schulz, had written a memorandum recommending the ban, quoting Beneke’s claims that reason is a refined form of sensibility and that thinking is a purely natural process. No one told Beneke this. He was left in the dark. He appealed up the chain, even to the crown prince, and finally met Altenstein, who told him bluntly that any philosophy that cannot explain everything in relation to the Absolute is no philosophy at all. Beneke’s supporters saw Hegel’s hand. It is unclear whether Hegel intervened. Another explanation is bureaucratic. Schulz, tasked with enforcing the Carlsbad Decrees, may have seen Beneke’s book as dangerous to public morals and religion. Either way, Beneke was out of a job. Jena wanted him as Fries’s replacement, but only if Altenstein wrote that he had nothing against Beneke’s hire. Altenstein refused, saying that though Beneke’s character was sound, his writings showed intellectual immaturity and unfitness to teach. Under the Decrees, a ban in one state closed doors in the rest of the Confederation. He tried in Göttingen in 1824, habilitated, and lectured with some early success, but the students there did not care for philosophy, and he could not make a living. He returned to Berlin in 1827 and petitioned until he was reinstated as a Privatdozent. He then fought for years for promotion. His lectures were popular and his books well received, yet money was scant. He used to say that as an unpaid extraordinary professor who still had to pay into the widows’ fund, he had a negative salary. Even after Hegel’s death, the ministry tried to preserve his legacy by appointing Hegelians. Beneke networked with English scientists more congenial to his outlook. After Altenstein died he finally received a small salary, but he was never made a full professor. He disappeared on the way to lecture in March 1854. Two years later his body was found near Charlottenburg. Robbery looks unlikely. Ill health, isolation and repeated passed over promotions point to suicide as the likeliest cause. It is a sad ending to a hard life. Soon after his epiphany he set to work on the foundations. At twenty one he wrote his first book, the Doctrine of Cognition, finished in May 1819 and published in 1820. It laid down his epistemology and guided his later work. The preface shows his ambition. He wants to complete Kant’s revolution. He thinks Kant’s promise has not been fulfilled. The Critique of Pure Reason has produced more conflict, not lasting peace. He even blames Kant. Kant called for a law book of pure reason to judge disputes among philosophers, but failed to found it properly. Beneke’s book aims to supply the basic rules if not all the precepts of that law book. He says we must start from the theory of judgement. What is a judgement, and what makes it true or false. Kant rightly began with a classification of forms of judgement, but the scheme is flawed, so the Critique rests on a poor base. For Beneke, every judgement compares two mental activities, one standing behind the subject term, the other behind the predicate. A judgement is true when those activities are wholly or partly identical. In other words, it is true when the intuition behind the predicate is contained in the intuition behind the subject. “This lily is white” says my intuition of white is part of my intuition of this lily. On this picture all true judgements are analytic, in Kant’s sense. So Beneke abolishes Kant’s analytic and synthetic divide. He thinks Kant went wrong because he took the subject of judgement to be a concept of the thing. If you do that, some judgements will be synthetic because the concept of the subject does not include the predicate. But the proper subject is not a concept. It is our whole intuition or perception of the thing. Taken that way, the predicate is included after all. He admits there are synthetic judgements when our perception of the subject is incomplete. Full identity between subject and predicate is an ideal that we reach only in science, where we hold an adequate grasp of the subject. Whether a judgement is analytic or synthetic depends on how we define the subject, and we define it pragmatically for our purposes. In ordinary life many judgements are synthetic because our grasp is thin. In science they become analytic as our grasp improves. A judgement analytic in one science may be synthetic in another, because the terms are defined differently for different ends. He applies the same treatment to mathematics. Kant’s claim that mathematical judgements are synthetic a priori looks plausible because it is hard to see how the predicate sits inside the subject when we say the three angles of a triangle equal two right angles. Beneke says that with further analysis of the subject term we can make such judgements analytic. He concedes that proofs often begin with intuitions. We then refine the intuition and define the subject so that it is equivalent to the predicate. From here it follows that mathematics does not need space and time to be a priori forms. If mathematical truths are analytic in the end, their truth would stand even if space and time turned out to be empirical. Beneke knew that identity alone does not give knowledge. A mere formula, an identity, by itself has no necessary bite on reality. “All dryads live in the forest” is as much a strict identity as “All bodies have weight.” For a formula to count as knowledge it must apply to reality, to being itself, and we can only tell that by consulting experience. What separates knowledge from fiction is perception. This is the core of his empiricism and, as he sees it, the bedrock of his agreement with Kant. Two difficulties arise at once. First, he stresses that no amount of experience can confirm a universal judgement. To be true, it must hold for all cases, and a complete induction is impossible. This means a lot of the universal claims in empirical science are not strictly true. They only become true by decision. We fix the meaning of the subject term so that the predicate follows from it. That move solves one problem and opens another. Do these tidy definitions tell us anything about reality, or are we just playing with words. We have no guarantee we have not built a theorem like all stags live in forests. It is consistent and empty. A second problem bites harder. Beneke wants objectivity, not just reports about his own mental states. Yet he also insists that what we know first are our own representations. If that is right, we need some way to sort the representations that latch onto things in space from the ones that are mere appearance. Only then do we have objective knowledge. He flags the need for a criterion, then does not give one. The result is a hanging bridge. It looks like the knower may be trapped inside the circle of consciousness, with no safe crossing to things. Even so, Beneke thinks his account gives the Critique of Pure Reason the foundation it lacked. Truth now has a clear test. A judgement is true when the subject and predicate are identical, either fully or in part. He admits most judgements fall short of that ideal. Ordinary thought and even much scientific work do not command a full grasp of the subject. The point is not that we already meet the ideal, only that we can see it. That sets the target for inquiry. Kant’s talk of synthetic a priori judgement, by contrast, leaves the court of critique without a usable test. How do we know when such judgements are true. Kant answers with transcendental deductions. Beneke finds these arguments scholastic and fragile. Step back and the whole of Beneke’s doctrine is a strange alloy. The truth test is Leibniz’s predicate-in-subject principle in modern clothes. The talk of comparing ideas to check agreement or identity echoes Locke. He demands that true judgements be faced with experience. Yet he also dreams of a deductive system for the sciences, a mathematical philosophy in the spirit of Newton, which proves basic truths. The risk is obvious. That can slide back into the scholasticism he blames on Kant. The tension is manageable if we place the mathematics at the end of inquiry, not at the start. Build the system to organise and compress what observation and experiment have already secured, not to guess it in advance. Soon after the Doctrine of Knowledge, Beneke published the Doctrine of the Original Soul. The two books are a pair. The second states and defends the psychological programme behind the first. For him, epistemology belongs inside psychology. If you want to study the powers and limits of human knowledge, you are studying the human mind. That conviction drove the earlier book and now gets justified. The new book is his first full statement of a young man’s plan to remake philosophy. It lays a psychological base not only for knowledge, but for aesthetics and ethics too. It is not a full psychology. It gives just enough to stabilise the main parts of philosophy, because the endgame is bigger. In time, he wants all philosophy to become the natural science of the human soul. Why psychology. First, because psychology can, in principle, be an empirical science. It can observe, compare, correlate, and induce, just like physics, chemistry, biology, and physiology. True science rests on perception and on experience made coherent by comparison. If epistemology sits on psychology, and psychology follows those methods, then the study of knowledge can be a science rather than a scholastic scheme. Second, because to understand what we know we must understand how we know. The mind’s activities shape the object for us. Self-knowledge of those activities is the key to knowledge as such. In this spirit he calls psychology the most basic science. It is the science of science, because the soul is the medium and instrument that makes science possible. All knowledge is by humans, for humans, and about humans in this minimal sense, because it depends on our powers of perceiving and forming the world. Third, there is a theory of meaning lying underneath. We already saw it at work in the Doctrine of Knowledge, where judgement is analysed into mental activities. At the end of the Doctrine of the Original Soul he makes the basis explicit. We identify and name objects through basic mental acts, above all speaking and hearing. Words that designate what we know are products of those acts, so their meaning ultimately comes from them. Put differently, what we know is constructed by activities within us, so the words that designate what we know are grounded in those activities. Outside these activities, he says, there is nothing in a human being, and therefore nothing for a human being. The complete articulation of simple and complex activities exhausts the secret of human knowledge. The upshot is stark. Beneke presses toward dissolving any robust gap between mental acts and their objects. Intentional objects are not a separate province that stand over against the acts. They are the products of those acts and so receive their sense and their reference from them. Treating intentional objects as if they were free-standing things is, in his eyes, reification. From a Kantian angle, this looks like a relapse into the old empiricism Kant tried to surpass in the First Critique. In Beneke’s defence, he thinks going back is the only way forward, given the defects of Kant’s method. Kant never, in Beneke’s view, examined the basis of his own way of arguing. Kant’s method is a priori reasoning. His standard of knowledge is possible experience. How can those sit together. If you are serious about possible experience as the standard, then epistemology should use the same empirical methods as the sciences. On this charge of scholastic method in psychology, Beneke stands with Fries and Herbart. The empiricist psychological tradition meets Kantian orthodoxy head on. His method is observation and induction. Psychology should collect and compare phenomena, find common features, and trace them to causes. Later he calls his method genetic. Break complex mental events down into simpler elements. Show how they arise and combine. He says little about experiment. He is still far from the laboratory style that Fechner, Müller, and Weber will develop in the 1830s. His observation is largely introspection. When in doubt, he tells you to look within. That is how the original soul theorists always worked. His programme is reductive. He wants to explain all mental activity as the appearance or function of what he calls basic activities. These include the activities that sustain animal life, such as digestion and reproduction, the senses, and the muscular movements that action requires. It sounds like materialism, though that is not his aim. He says mind and body cannot be pulled apart inside these basic activities. They are physical and mental at once. He also insists the mind is not passive clay. It reacts and initiates, it is active as well as receptive. For all the reduction, there is also holism. A human being is indivisibly one. To act in any particular way, the person must act as a whole. The whole person must be active if any activity is to arise. The point of the explanatory programme is to show how all activities belong to one living being, and to stop cutting the soul into independent faculties. Even so, Beneke does not throw out the word faculty. He prefers activity because it fits his belief in life and energy, but he does not think the faculty concept is wrong in principle. A faculty should name the arousal of an activity in a thing when it meets the right stimulus. It should name a kind of activity. We should not mint a new faculty for every effect. First classify the kinds of activity, then talk about the basic faculties. In that order, activity remains more basic than faculty. He claims all the higher activities of the soul rise from the environment’s action on the basic activities and from the way these activities combine. Association and repetition do most of the work. Repeat similar stimulations and weaken different ones and concepts form. Tie a sound to a concept and language appears. Assert in words that one mental activity is the same as, or part of, another and you have a judgement. There is no need to posit separate, independent powers for concept formation, language, or judgement. They are functions of the basic activities. For the same reason, there is no need to posit a special inner sense for self-awareness. Awareness of ourselves arises only after basic activities reawaken impressions they have had before. Although he insists on unity, he still draws one important distinction. There are two main series of activity at work in knowledge. One series comes from perceiving, that is, the stimulation of the senses. The other comes from connecting and relating what has been perceived, mainly through cause and effect. He treats cause and effect as built from constant conjunctions in succession. This echoes Locke’s ideas of sensation and reflection. He is keen to keep the distinction empiricist, not transcendental. The a posteriori and the a priori are not two sources. What Kant calls a priori, Beneke says, ultimately comes from experience. The so called a priori concepts are the widest abstractions we form from experience. We think something is innate only because we have not yet given an account of how it arose. He later softens this and admits the mind has inherent activities that make knowledge possible at all. But in the early work the empiricist line is sharper. On the back of this psychology, he draws more conclusions for knowledge. He says the whole question whether our knowledge is subjective or objective is vague. Some senses are more objective than others because different people converge. People often see or hear the same thing, and the same person can do so at different times. All the senses are still both subjective and objective to some degree because they depend on inner activity as well as external stimulus. Drawing a clean line between the inward and the outward component is hard because receptivity and spontaneity intermix. Even so, psychology gives some support for thinking there are things in themselves. He does not defend Kant’s exact term, but he holds that the stimulus behind perception and the object itself lie beyond our cognitive reach as perceivers. We can think about and perceive the world only as it reveals itself to us. The hard test for his empiricism is whether it can justify the laws of natural science. The important claims are universal and necessary connections between kinds of events. Kant rejected empiricism because he thought it could not carry those claims. Hume had already shown that experience gives constant conjunction, not necessity. Beneke knows the problem and confronts it. He repeats what he said earlier. Universal judgements are valid only if they hold for all cases, and we can be certain of that only with complete induction. No induction is complete. By rights, this should mean all natural science is uncertain, however good our observations and experiments. He half accepts that. He even endorses Hume’s reduction of causality to constant conjunction. Then he hesitates. Rather than say out loud that all universal claims in science are uncertain, he reaches for a different pattern of justification. There is mathematical construction. From a single constructed case, we can see a universal truth. Take a triangle. From one construction we can see its interior angles add to two right angles. He suggests all universal judgements arise in that way. He does not explain how this could work outside mathematics. The Doctrine of the Original Soul, like the Doctrine of Knowledge, leaves the foundation of knowledge suspended. The book then turns to aesthetics and ethics. First he offers a new foundation for aesthetics as a theory of feeling. Feeling arises from the ratio in the mind between what it receives and what it exerts, between stimulus and energy. There are three basic kinds. Pleasure when stimulus predominates over energy. Sublimity when energy predominates over stimulus. Beauty when stimulus and energy are in equilibrium. This stripped down scheme for feeling then becomes the base for his ethics. For Beneke as for Herbart, ethics rests on aesthetics, because ethics rests on human feeling and the study of feeling is aesthetics. We judge actions by the feelings they arouse. Virtuous actions prompt feelings of sublimity or beauty. Vicious ones prompt their opposites, the common or the ugly. If you admire Kant, this will feel like a swerve. Beneke goes against Kant on key points here. He treats practical reason as an occult quality and wants to decompose it into elements found in feeling. More radically, he wants to scrap the entire doctrine of duties and replace it with a doctrine of virtue. Judging actions by abstract rules, he says, is a mistake. It ignores the detailed features of each case and levels everyone to a single standard of mediocrity. Like a good student of Schleiermacher, he thinks absolute duties miss the role of individuality. Motives differ. Circumstances differ. Constraints differ. Moral judgement must be aesthetic because it is about learning to sympathise, to reconstruct another person’s state of mind. Feeling has the advantage. It is more sensitive to individual features and so more likely to judge fairly. The political point follows. The doctrine of the original soul comes with a liberal social aim. It wants magistrates and judges to see the world from the defendant’s point of view. That makes for tolerance and humane judgement. That is the skeleton of Beneke’s early programme. It is rough and dense. In a brief book he thought he had found the foundation for the philosophy often sought and rarely caught. He wrote with the certainty of youth. He even claimed his philosophy was not one philosophy among others but philosophy itself. Around the same time, Beneke crossed paths with another ambitious young lecturer in Berlin, Arthur Schopenhauer. Both qualified to teach in 1820, though Schopenhauer began one term earlier. Beneke went to Schopenhauer’s lectures twice that spring. He also reviewed The World as Will and Representation at the end of 1820 for the General Literary Newspaper. This was risky. They were rivals for the same students. Beneke tried to be fair. He would be frank about content without turning it into a personal feud. He notes Schopenhauer’s deep respect for Kant despite sharp critique. He asks for the same spirit in return. His summary is generous and severe in the same breath. The book shows great philosophical insight, riches of thought, and a rare gift for clear and vivid exposition. It contains many illuminating remarks across philosophy. And yet, he concludes, the reviewer must now end this praise and say there are many errors bordering on madness, caused by consistent deduction from a few false principles. The review is long and intelligent. Beneke tests Schopenhauer mostly by Schopenhauer’s own standards. He points to tensions. Schopenhauer limits knowledge to experience, then claims knowledge of reality in itself. He confines the principle of sufficient reason to appearances, then says the will in itself causes appearances. The deepest error, Beneke thinks, is the jump from narrow premises to sweeping metaphysics. The immediate knowledge we have of our mental activities is not enough to infer a single cosmic will present in all nature and all humans. By the end, the fault line is clear. Beneke’s cautious empiricism collides with Schopenhauer’s ambition. If philosophy is a science, it must accept the limits of science. Where does this claim to know the inner nature of things come from. Beneke knew he was skating on thin ice. Schopenhauer was notorious for contemptuous attacks on other philosophers. Beneke tried to head off a feud by asking for restraint. It failed. Schopenhauer was furious. He wrote to the editor, Heinrich Karl, demanding immediate publication of his reply without editing. If refused, he would take it to other journals and add his account of the affair. He did not object to criticism, he said, but to lies. He accused Beneke of fake quotation, of stitching phrases, omitting words, and adding others while still using quotation marks. That was slander. The journal printed Schopenhauer’s rejoinder with Beneke’s reply. Beneke’s answer was simple. Some changes were printer’s errors. Most were abridgements for readability and space, a normal practice. None altered meaning. Another review had done the same. As for the tone of Schopenhauer’s reply, it condemned itself. Beneke added one detail. He had twice tried to visit Schopenhauer at his lodgings to discuss things in private. Both times he was turned away by the maid, who told Schopenhauer after the second visit that the poor young man turned completely pale. Schopenhauer relished the scene. The skirmish foreshadows later fights between Schopenhauer and the neo-Kantians. He despised university philosophers. He was contemptuous of Herbart and Fries as he was of Beneke. The later neo-Kantians will return the favour. Back to Beneke’s ethics. In 1822 he published The Elements of a Physics of Morals. It develops the ethical theses sketched earlier. The programme is naturalist. Feeling is central. Absolutist morality is rejected. One change is striking. The aesthetic foundation, so prominent before, moves into the background. Beauty and sublimity mark two kinds of virtue rather than serve as the base. Kant remains the decisive figure, but mostly as the opponent. The subtitle says it all. It is written against the Metaphysics of Morals. The book takes the form of letters to an imaginary Kantian named Karl. After twenty long letters, Karl converts. He sees that almost every plank in Kant’s moral theory fails. What is a physics of morals. He later adds an appendix and apology to clear up the phrase. It sounded materialist, which he denies. Physics here means nature in the old Greek sense. The physics of the soul means its nature. He is clear that the nature of the soul is distinct from matter. Still, he is a naturalist. He wants to explain the characteristic phenomena of the soul under natural laws. He even endorses a Leibnizian naturalism where nothing is supernatural and everything happens of necessity. In the politics of the 1820s that alone was enough to invite trouble. When Schulz complained about Beneke’s book, he did not say materialism. He objected to the claim that thinking is a purely natural process. The Physics of Morals tries to rehabilitate the sentimentalist ethics of Hutcheson, Hume, and Smith, which Kant first adopted and then rejected. The immediate German source is Jakob, who imported Rousseau’s sentimentalism. Beneke says Jacob’s views are closest to his own and credits him with the idea of a genetic account of morality. The central thesis is straight sentimentalism. Moral principles arise from sentiments and must be based on them. We know right and wrong first by feeling, then we articulate and refine them into concepts and principles. So it is not principles that ground our feelings. It is our feelings that ground our principles. Concepts and principles are still needed to clarify and explain, but they never replace feelings and must rest on them. If we were purely rational beings with no sympathy, we would have no reason to be kind. We approve benevolent acts and disapprove selfish ones because we feel sympathy. From here he assumes there is a special class of moral feelings. Ethics must discover, define, and clarify them. Feeling has been ignored, he says, because philosophers misunderstand sensibility. They treat it as passive and physical, opposed to reason. In reality it is active and spiritual. Following Hume and Jakob, he makes sensibility the source of vital energy and the leading power of the soul, with reason as a function of it. The flip side is a hard critique of Kant. One more reason to be an empiricist and a sentimentalist in ethics is that rationalism fails. The categorical imperative repeats the same error as every rationalist scheme. It tries to squeeze determinate results out of a purely formal universal. The imperative is empty. Any maxim, moral or immoral, can be made universal. The only reason Kant’s principle seems to work is because his arguments quietly smuggle feelings into the test. It is feeling that tells us whether we can will a maxim as a universal law. Mostly, he finds the criterion too vague. Kant does not tell us how to formulate a maxim, so results shift with the phrasing. He does not specify the moral will with enough precision either. In line with Herbart, Beneke denies there is any special moral value in universality. Immoral rules can be universalised just as well as moral ones. The universal versus particular distinction is only logical. Focusing on universality distracts from the real work, which is to see the special circumstances and mixed motives in each case. Each case is unique. Each agent is different. Generalising is nearly impossible. Here, he says, you see the strength of feeling over the universality test. Feeling can register differences. It is more likely to yield tolerant and accurate judgement. He goes further. The worst part of Kant’s theory is its absolute values. No value is so absolute that there is not a higher one above it. None is so unconditional that it should never be surrendered. Take the ban on killing. It seems the most absolute. Yet even that has exceptions. In famine the Greenlanders killed their children rather than watch them starve. Kant tells us to treat humanity as an end in itself. Yet we execute criminals. We command soldiers to die. Beneke accepts a mild relativism. Approval can differ over the same type of action. Whether we approve of polygamy or suicide should depend on circumstances, time, and the agent’s age. A moral science that claims to float free of time and place is dead. Legitimate moral science must be partly historical. Given all this, it is no surprise he moves toward a virtue ethic. There are no general rules that hold for every case. What we ought to do can be known only by attention to particulars. A general rule has no moral force because it cannot tell us whether and how it applies in a concrete setting. A proper imperative is not be kind but be kind here. He ties the law to the image of the virtuous person. He quotes a maxim he attributes to Aristotle. The good is what the excellent person does. He even defines morality as having power over sensible desires and following a system of values, whatever they are. Since morality does not depend on fixed precepts, he leaves open what those values should be. People can be virtuous, meaning moral, whatever desires they control and whatever values they hold. Even so, he does not throw out general principles entirely. He says that in some concrete cases we can determine right and wrong with mathematical accuracy. The method is not the categorical imperative but a kind of utilitarian calculus. We weigh gains and losses and choose the option that maximises pleasure or minimises pain. He tempers this by rejecting consequentialism in a strict sense. Success does not settle morality. Motive does. The tension eases if we keep apart rightness in law and rightness in morality. The legality of an act concerns consequences. Its morality concerns motives. Nothing in Kant angers him more than metaphysical freedom. It violates his naturalism. The Kantian idea of a noumenal self is, for him, obscure. It makes no sense to put moral motivation and character beyond time and space. Volition and action occur in time, so by Kant’s own lights they belong to nature, which covers the temporal realm. Kant wanted to save freedom from natural necessity. Beneke says freedom does not exclude causation. All freedom presupposes is power over our impulses and absence of constraint. Neither requires that an act be without a cause. All acts have causes. That does not make the will superfluous. The will is one of the necessary causes. He argues, like a compatibilist, that morality not only fits causal necessity but presupposes it. Moral advice has the form do X if you want Y, which assumes X causes Y in the right conditions. The Physics of Morals was bold for its time. The 1820s still belonged to Kant and to speculative idealism. Empiricism, naturalism, and relativism were bound to provoke. It is no surprise the book helped trigger the order that shut down Beneke’s lectures in Berlin. That stigma stuck. He never lived it down. After the Doctrine of the Original Soul appeared, Beneke saw cracks in his foundation. His revolution depends on psychology being an empirical science. That belief needed defence. There were strong critics who doubted psychology could be a science at all. Answering them became a priority in the early 1820s. He did this in three works: New Elements of Metaphysics, On the Relation of the Soul to Life, and On the Development of the Soul and the Cultivation of the Soul. One critic was Kant himself. In the First Critique Kant treated psychology like a stern stepfather treats an unruly ward. He allowed it as an empirical discipline, but only as applied philosophy, and banished it from pure metaphysics. Psychology had not proved itself. It scarcely counted as a discipline. One had to suffer it for a time, then send it to its proper lodging in a comprehensive anthropology, the pendant to empirical natural science. In the preface to the Metaphysical Elements Kant went further. A discipline is scientific only to the degree that mathematics applies. Inner sense is too fleeting for mathematics, so empirical psychology cannot be a strict science. Worse for Beneke was Kant’s doctrine of inner sense. We know ourselves only as appearances. In the First Critique Kant says we know we exist as spontaneous subjects, but not how we exist, because the subject as such is unknowable, a thing in itself. The reasoning is simple. All knowledge, including self-knowledge, is limited by the form of inner sense, which is time, and time gives us appearances, not things in themselves. The result is to downgrade self-knowledge from the privilege it had in early modern philosophy. Descartes, Locke, and Hume all treated self-knowledge as direct and secure, while knowledge of the external world was indirect and fragile. Kant puts them on the same footing. Both are certain and immediate, and both are about appearances. The thing in itself, whether as external cause of sensation or the subject that stands behind representations, is unknowable. Beneke aims to restore the primacy of self-consciousness. In New Elements he tries to refute inner sense more geometrico. He wants to prove that we know ourselves as we are, and that self-knowledge is privileged over knowledge of the external world, which must be inferred from inner states. It is odd to see an empiricist take up mathematical demonstration, but Beneke thinks the question is not empirical and so calls for exact metaphysical method. He also doubts Kant’s split between mathematical and philosophical methods. Philosophy can have the same exactness if it follows the method with rigour. He thinks his first proof is enough to defeat Kant. The task is to find one representation that corresponds with being. He finds it in the very act of becoming aware of a representation, because that representation, as a representation, has being of its own. It does not matter whether it also corresponds to something else beyond itself. It exists as something in its own right. The facts that we can be aware of this representation and that it exists are enough to show we can know being, at least in our own case, by awareness of our own representations. The argument does not carry the weight he puts on it. The question remains whether the representation we know belongs to us in ourselves or only as appearance. The representation counts as being in a very thin sense, which leaves open whether it is being in itself or appearance. There is also the regress. How do we know the act of representing without another act that knows that act, and so on. This was the kind of problem that haunted the young Herbart, who did not miss the chance to press it on Beneke. Beneke comes at it again in On the Relation of the Soul to Life. He explains the earlier proof in plainer words and adds an argument. Knowing the external world requires us to go outside ourselves to check whether our representations match something beyond us. Knowing ourselves does not. What we know is before us in immediate self-observation. The difference, he says, is basic. Kant’s doctrine denies it and makes self-knowledge look as hard and problematic as knowledge of the world outside. Again the argument is thin. If all cognitive activity conditions what appears, as Kant says and Beneke concedes, then self-knowing should also condition what it knows. The subject must, in a sense, go outside itself to know itself as object. The distinction between knowledge of self and knowledge of world collapses. That is the price of the Kantian principle that cognition shapes its object. Another critic was Hume. Beneke admired Hume and read him in English. He had even endorsed Hume’s account of causation as constant conjunction in the Doctrine of the Original Soul. Later he realised what follows if you take that line. It undermines not just laws of nature but laws of mind. He tackles Hume’s scepticism head on. He agrees with Hume’s test. We can show that an idea is real only if we can find an impression that matches it. On that basis, Beneke says, we can save the idea of causal connection. We have an immediate feeling of power in willing. When I resolve to close the door, I feel my effort. I feel the force that pushes the door against the resisting air and into the frame. That feeling, he says, is a simple impression of force or power. It grounds the idea of necessary connection. It is given and simple. It is not built from other impressions. Imagination can join and separate impressions, not create them. It is no surprise that this old move fails. Hume had already answered it in the Enquiry. Beneke himself had rejected it earlier. Now he tries to revive it out of need, because too much is at stake. He combs through Hume’s objections and tries to escape them, but the effort convinces no one. A feeling of effort may be real, but it does not carry necessity with it. A feeling of effort may be real, but it does not bring necessity with it. At most it gives you the texture of trying, not the law that binds events. Even if willing often goes with moving, it does not follow that willing must produce moving, or that the link is necessary rather than learned. Hume’s point returns intact. From what is felt you cannot squeeze what must be. Beneke senses the danger and steps back from the brink. He does not abandon laws. He reframes them. Psychology can still have laws, he says, but they will be genetic and comparative, charting degrees of force, patterns of association, typical sequences. Their necessity is not the iron form of geometry. It is the stable regularity of life as we live it and as education can shape it. On this softer ground his project can still stand, though it no longer answers Hume on Hume’s terms. He also leans again on construction, but now as method rather than proof. In mathematics the single construction shows the universal. Outside mathematics, construction means controlled formation of habits, trials of attention, training of memory. What is universal here is the program for producing effects in minds like ours. The law is normative and practical, not metaphysical. Once more the system breathes by pedagogy. This move has costs. If the strength of a psychological law lies in what well-run training can reproduce, then objectivity shades into technique. The measure of truth becomes what we can reliably bring about in a mind. That keeps science empirical and usable, but it leaves the old question open. Do these procedures answer to things, or only to us. Against Kant he holds the line on self-knowledge. We know ourselves first and best, because the acts we perform are present to us as we perform them. Against Hume he holds the line on lawlike order, but he concedes the order is won by formation, not given by insight into necessity. Against Herbart he defends life and activity against a purely mechanical play of representations, yet he borrows Herbart’s talk of degrees and thresholds to keep measurement in view. So the section ends with a balance. The universal in psychology is no longer an eternal link between ideas. It is the stable effect of formation under repeatable conditions. The necessity we can claim is the necessity of method: if you arrange the inputs and the training like this, expect the output like that. It is enough for an empirical science of mind and enough to keep philosophy tied to experience. It is not enough to silence the old sceptic. The cracks remain visible, even as the scaffolding holds. Such very crude attempts to pull thick content out of thin thought could not convince anyone who was not already on side. The old promise that reason alone could found the whole of knowledge looked like a conjuring trick once you watched the hands. There was a second pressure too. The new sciences were booming. Physics, chemistry, physiology and history were carving out their own territories with their own tools. As they did, the grand claim that philosophy would sit above them and legislate for all began to sound hollow. If chemists could discover laws at the bench, and physiologists could map functions in the brain, what was the philosopher to add from an armchair. So philosophy fell into an identity crisis. If it could not found everything from first principles, and it could not compete with laboratories and archives, what was it for. Some said it should retreat into history, telling how ideas had risen and fallen. Others said it should become logic and method, examining how inquiry works wherever it happens. Others still wanted it to return to the subject, and rebuild everything from a careful psychology of knowing. The criticism of the old systems cut in two ways. First, you cannot get existence out of essence. Second, you cannot get the concrete out of the abstract. Those were Kant’s lessons against the ontological proof and against the paralogisms, and the lessons stuck. To insist that they did not was to ignore the very point of the critique. At the same time the best scientists of the age kept pushing on method. They rejected private intuitions and grand a priori constructions. They asked for testable claims, careful measurements, clear concepts tied to operations. Their attacks on Naturphilosophie were not only about results, they were about how you get results at all. Against this background the way forward for philosophy began to take shape. Stop pretending to legislate for nature. Start clarifying how claims get their warrant. Ask what counts as a good explanation in mechanics, in physiology, in history. Map the limits of each field, and the kinds of concepts they can rightly use. In short, do critique as analysis of methods rather than as system building. That shift kept much of Kant’s spirit while dropping his old scholastic habits. Keep the limit claims. Keep the insight that knowing is conditioned by our forms of inquiry. Drop the hope that pure reason can spin the whole web. Replace deduction from first principles with reconstruction of practice. It also preserved what the lost tradition had kept alive. Transcendental idealism as a limit doctrine. The stress on experience as the tribunal. The warning that teleology is heuristic rather than constitutive. The dualisms needed to keep talk clear, like form and matter, understanding and sensibility, essence and existence. There were models to hand. Trendelenburg worked the link between logic and motion, showing how thought borrows from the forms of action. Helmholtz tested sensation with instruments, then drew cautious conclusions about space and time as forms of representation rather than things. Lotze, for all his eclectic air, pressed the line that values and meanings require a different type of account from bare causes. Each in his way nudged philosophy toward an analysis of concepts and methods that the sciences themselves tacitly employ. Once you see the role like that, the old feud with materialism also looks different. You do not answer the physiologist with a metaphysical ghost. You ask what kinds of explanation brain science can give, what it must presuppose to measure and compare, where its concepts apply, and where they do not. You do not deny dependence. You sort kinds of dependence, and you show why some questions change their form rather than vanish when physiology advances. By the end of the 1850s the outlines were clear even if the names were not yet fixed. Philosophy would justify from within practice rather than from above it. It would study validity rather than invent substances. It would be critical and empirical at once, not by doing experiments itself, but by making sense of what experiments mean and what they cannot mean. Out of that settlement the later revival would grow. When the return to Kant came, it would be a return to his questions and his limits, not to the dream of a new system. The path had been cleared by the fall of the grand constructions, by the surge of the sciences, and by the stubborn efforts of those who refused both easy scepticism and easy dogma. since as good students of the critique they denied that sensation alone could yield objective structure, they found themselves driven to say that something must strike the senses in the first place. If form comes from us, matter could not. The thing in itself reappeared as the dark correlate of affection, the unknown source of the given upon which synthesis works. They hesitated to call it a being with properties. They hesitated equally to treat it as a mere word. In that hesitation lay the unresolved centre of the decade. Fischer tried to soften the point by treating the thing in itself as a boundary concept. It marks the limit of what can be said, not an item that could ever be described. Zeller leaned on antiquity to the same end, reading the motif as a critical heir to the apophatic discipline of negative theology, knowledge by denial rather than by predicate. Liebmann, more impatient, kept repeating the watchword back to Kant and urged that the troublesome phrase be handled with economy. Keep it where the deduction needs a bearer of affection, but do not let it out into speculative daylight. Lange, always the subtle synthesiser, folded the issue into his account of the symbolic character of representation. If our science builds sign systems that track lawful relations, he argued, then reality in itself is the unknowable ground whose effects are encoded in those lawful signs. None of these moves removed the pressure. Each tried to state what must be presupposed without pretending to know it. The same tension surfaced in their stance toward naturalism. Against the materialists they insisted that explanation by causes presupposes rules of synthesis that are not themselves causal products. Against the old rationalists they insisted that such rules are not free inventions either, for they fix what counts as experience at all. The term a priori kept both sides of this truth in play. It named what is not read from experience and yet is only meaningful in relation to experience. By reading the a priori through psychology they hoped to give it empirical credentials without surrendering its necessity. By the end of the decade this bet began to look costly. Two cracks widened first. One concerned method. If the critique establishes conditions of possibility, it cannot be a chapter within any first order science. If psychology is a first order science, the critique cannot be psychology. Fischer and Liebmann said as much, even as they continued to use psychological language. The second concerned normativity. Even the most careful laboratory work yields regularities. It does not by itself tell us which rules a thinking subject ought to use when it claims knowledge. Norms do not reduce to habits without losing their authority. The more experimental psychology advanced, the plainer this looked. These troubles did not undo the achievements of the sixties. They set the agenda for the seventies. What would it mean to reconstruct the critique as a logic of validity rather than a natural history of cognition. How could one give an account of concept, judgement and law that is faithful to the sciences as they are practised while not collapsing into those sciences. How should one speak of reality in itself without sliding back to the metaphysics the critique had discredited. The answers would divide the next generation. On causality the sixties adopted a cautious dual register. In the empirical register they encouraged the search for lawful dependence and the reduction of qualitative impressions to measurable magnitudes. In the transcendental register they restated the principle as a rule for the unification of appearances, not as a truth about hidden powers. This let them oppose both the old occasionalism and the new vitalism while preserving the autonomy of method. Yet even here the unease remained. If the principle is only a rule, why does nature keep step with it so reliably. If it is more than a rule, how avoid the dogmatism that the critique forbids. On space and geometry the sixties accepted Helmholtz’s challenge without following him all the way. Non Euclidean geometries showed that the necessity felt in Euclid was tied to the way our space is constructed and measured. It did not follow that the form of outer intuition is empirical. Rather, the new mathematics helped them distinguish the form that any spatial experience must have from the metric that our scientists adopt for successful coordination of measurements. The one sets the conditions for representing bodies at all. The other is fixed by physical theory and experiment. The result preserved the insight of the aesthetic while opening room for physics to decide its own geometry. On value the sixties did groundwork that later schools would raise into a programme. The distinction between existence and validity, introduced to avoid both psychologism and scepticism, allowed them to explain how mathematical and moral truths claim objectivity without being things. It also let them resist the materialist slide from causation to norm. What is, does not settle what holds. That spare formula became a hinge for later developments. In pedagogy and public reason they played a practical role. The critical watchwords of autonomy and publicity armed liberal lawyers, school reformers and journalists against both clerical and statist reaction. Even those who disliked the jargon recognised the uses of a tribunal that no altar and no throne could overawe. The intellectual authority of the sciences helped, and the sixties made a point of standing with the sciences where they could, and showing limits where they must. The undecided questions, however, could not be deferred forever. As psychology hardened into a laboratory discipline with its own instruments, and as physics and physiology pressed further into the subvisible, the thought that philosophy could be a quasi science lost plausibility. Either philosophy had its own kind of question, with its own standards of answer, or it would become redundant. The better minds of the sixties saw this coming. They tightened their formulations, they pared their claims, they prepared the ground for a reorientation that would keep faith with criticism while cutting loose from the last remnants of a faculty psychology. The return to Kant had begun as a defence. By the close of the decade it had become a programme. It aimed to clear away speculative residues, to face the sciences without servility, to explain objectivity without metaphysics, and to hold on to the thing in itself as a limit thought rather than a theme for description. In the next phase that programme would split along two paths, one logical and one axiological, each convinced that criticism could only survive by giving up psychology, and each determined to keep the sciences as partners rather than pupils. context in which he had advanced them. The pamphlets read as if they were written to placate censors rather than to clarify doctrine. Their effect was the opposite of what he intended. They convinced his adversaries that he was trimming, and they worried some allies who preferred frankness to tactical retreat. The authorities did not relent. The venia remained withdrawn, and Fischer lived for several years by private teaching and literary work, sustained by friends in the neo-Hegelian circle and by a reputation that grew precisely because he had been silenced. The exile did not last. In 1856 he was called to Jena. The appointment restored an academic platform, but not tranquillity. The theological faculty there watched him as closely as Heidelberg had done, and the same mixture of admiration and suspicion followed his lectures. The students flocked to hear a brilliant narrator of systems who could make Spinoza lucid, Kant intelligible and Hegel persuasive. The authorities feared once more that persuasive exposition was already propaganda. Fischer did not change his tone. He believed that philosophy must be taught as a living unity of problems and answers, and that meant, for him, telling the story of reason as an inner drama that culminates in absolute idealism and then learns new discipline from critique. These years fixed the double aspect of his public work. On the one hand he published the volumes of his history of modern philosophy, each cast as a monograph on a master figure, each written with a literary grace that made difficult arguments accessible. On the other hand he developed the outlines of his own system in the paired treatises on logic and metaphysics. The history and the system leaned against one another. The history supplied the figures and the sequences in which problems sharpen and transform. The system supplied the standpoint from which the sequence could be seen as rational. This is why the Kantian and Hegelian strands in him never separated cleanly. He wanted Hegel’s architectonic without Hegel’s deduction of content from pure thinking alone. He wanted Kant’s critique without Kant’s strict prohibition on metaphysics. The result was a poised instability that critics could always expose and admirers could always forgive. When the Fischer–Trendelenburg dispute broke into the open, Fischer carried into it both of these habits. He read Kant historically and systemically at once. Historically, he insisted that the discovery of the a priori forms must be placed within the eighteenth century problem of securing mathematical physics against scepticism. Systemically, he argued that once this discovery is made, the possibility of an objective science of nature is saved without any appeal to things in themselves. Trendelenburg doubted both claims in their strongest form and pressed for the third possibility. Fischer’s replies often slid between exegesis and construction, and the sliding infuriated his opponent. Yet the same sliding made Fischer’s lectures so powerful. They presented Kant as a contemporary, one of us, whose problems were ours and whose solutions could be tested against present science. By the close of the decade Fischer had become a symbol of the Kantian revival and of its inner tensions. He proved that a gifted historian could rescue difficult texts for a broad public, he showed how a philosophy could be taught as a sequence of living options rather than a museum of dead opinions, and he demonstrated in his own attempts at synthesis how hard it is to keep faith with critique while preserving a metaphysical horizon. In 1872 he moved from Jena to Heidelberg, this time with honour and with a chair. The wounds of the earlier ban were not forgotten, but they had become part of the legend that now surrounded his name. Students who later led the movement learned from him a respect for problems rather than slogans, and a sense that the return to Kant was not a retreat from ambition but a reorientation of it. agency. From that premise Fischer thinks he is licensed to lift the as if into an is, moving from the reflective use of purposiveness to a constitutive ontology of will. The rhetorical force of the move is obvious. It promises a single key, the unity of the critical philosophy under the sovereignty of freedom, nature read as the gradual manifestation of an intelligible order whose inner form is willing. It also aligns Kant, retrospectively, with the grand teleological narratives of the century, rescuing purpose from mere heuristic and restoring to reason a world that is spiritually legible. Yet precisely here the Kantian scruple bites. The third Critique insists that purposiveness is a principle of judgement, not of things, that it guides inquiry where mechanism leaves lacunae, without entitling us to legislate reality in itself. The analogy with human agency is confessedly anthropomorphic and regulative. Fischer’s conversion of analogy into identity, and of regulation into constitution, transgresses this boundary. He inherits from Hegel the impatience with limits and from Schopenhauer the metaphysical appetite for an inner, unitary noumenal ground, then clothes both in Kantian terms. The result is ingenious and historically influential, but it is not Kant’s own doctrine. Schopenhauer’s shadow is long. The identification of the thing in itself with will, which Schopenhauer had trumpeted as his distinctive insight, becomes in Fischer’s hands a claim about Kant’s implicit intention. Fischer can point to scattered texts where Kant speaks of an intelligible character, of autonomy as self-legislation, of the primacy of practical reason, and of nature as if ordered to our moral vocation. But none of these passages authorise the leap from a practical postulate to a theoretical cognition. Schopenhauer consciously violates the critical limit; Fischer denies that a violation has occurred by redescribing the boundary as an inner articulation of one and the same system. The hermeneutic brilliance is undeniable; the exegetical warrant is slender. The contemporary reaction made this plain. Cohen objected that to construe purposiveness as an ontic property of nature is to abandon the method of the concept for a relapse into metaphysical hypostasis. Purposiveness, on the Marburg view, is a rule of synthesis that advances inquiry in the mathematical-physical sciences and in biology, not a window into a supra-empirical substrate. Windelband, along a different axis, warned that the primacy of the practical cannot resolve into a knowledge-claim about noumena without erasing the very distinction between validity and existence that secures the objectivity of value. In both cases the charge is the same: Fischer’s reading collapses the critical separation of standpoints. Fischer’s own defence appeals to unity. Without a single centre, he argues, the critical philosophy fragments into a dualism of nature and freedom. The architectonic demands an apex, and freedom supplies it; the will then becomes the intelligible kernel that makes sense of purposiveness in nature and obligation in morals. But Kant’s architectonic does not require ontological unification; it requires systematic coherence of principles within distinct uses of reason. The unity is methodological and teleological, not metaphysical. To insist on a one-substance solution is to import into critique precisely the speculative demand critique was designed to restrain. There is, however, a reason why Fischer persuaded many readers. His reconstruction speaks to the nineteenth-century need for significance. A purely regulative purposiveness can feel thin against the weight of historical and biological narratives that teem with apparent direction. Fischer offers a way to read those narratives as the appearing of freedom without capitulating to materialism. In this sense his proposal is best understood as a philosophical romance of reconciliation: a Hegelian hope to see the ideal in the real, recast in Kantian vocabulary. When measured by Kantian standards, the cost of the romance is high. The thing in itself ceases to function as a limiting concept marking the finitude of our cognition and instead hardens into a positive determination. The moral postulates shift from practical necessity to theoretical licence. The reflective judgement’s as if becomes dogmatic as is. Each of these shifts undoes, piece by piece, the critical difference between what can be known and what must be thought for the sake of action. Fischer’s later essays on freedom show the tension at work in a more concrete register. His adoption of the intelligible character doctrine allows him to preserve responsibility alongside natural necessity in appearances. But once the will is promoted to the noumenal essence of the world, the very distinction that made responsibility intelligible begins to blur. If nature is the appearance of freedom, then natural necessity risks becoming a mere mode of will’s self-display, and the hard edge of obligation softens into a descriptive metaphysic of development. Kant’s severe dual standpoint, which grounds the authority of the moral law, is thereby sentimentalised into a panorama of moralisation. The historical irony is that Fischer’s Kant helped to produce both of the main Neo-Kantian responses that rejected his synthesis. The Marburg school radicalised the methodological reading, refusing all noumenal talk and recasting the thing in itself as a task-concept for the advance of exact science. The Southwestern school shifted the centre of gravity toward value, distinguishing validity from being in order to protect normativity from naturalisation. In each case, the impulse is Kantian: to save critique from the temptation, brilliantly exhibited by Fischer, to make it a metaphysics by other means. Fischer remains, for all that, a decisive mediator. He taught a generation to take Kant seriously, to articulate the problem of knowledge, to read the aesthetics as foundational, and to place freedom at the heart of the system. He also displayed, in his very irresolution, the attraction of a unified picture and the danger it poses to the critical limit. The lesson is double. Without the longing for unity, philosophy withers into technique; without the discipline of critique, it swells into dogma. Fischer’s project lives between these poles, exemplary in its reach and instructive in its excess. Marburg. He would first need to run the gauntlet once more. The Hessian authorities examined his writings and sermons with a suspicious eye and there was predictable agitation from conservative pulpits. Yet the liberal ministry held its nerve and in the spring of 1849 Zeller took up the chair in theology, moving shortly thereafter to philosophy. The transfer was more than administrative. It registered a deepening conviction that the critical work he wished to pursue belonged not to ecclesiastical dogmatics but to philosophy understood as an examination of knowledge and its conditions. Marburg proved a turning point. The long labour of the Philosophie der Griechen began there, and with it the habits of philological exactness that shaped his later Kantianism. Zeller’s method was simple to state and demanding to practise. Every claim must be tied to texts, every textual claim anchored in provenance and context, and every context reconstructed with the best historical tools available. In that school of slow reading he learned to distrust the speculative shortcuts that had tempted the Hegelians. Form and content had to be kept apart for the sake of clarity. Where content is historical and contingent, form cannot conjure necessity out of it. That lesson sat behind his later polemics against the generation of content from pure thought. From Marburg Zeller moved to Heidelberg in 1862. His inaugural lecture announced the programme that would mark him out as a leader of the revival. Philosophy must secure its own field by taking as its task the problem of knowledge. That requires the dualisms Kant had articulated. Sensibility provides matter, understanding provides form, and the distinction safeguards us against the illusion that the laws of thought can yield objects by themselves. In the new division of labour among the sciences, this second order reflection protects both science and philosophy. It protects science by refusing to trespass on its empirical domain. It protects philosophy by refusing to treat it as a poor cousin of physics. Zeller’s neo Kantianism also took a public stand in the Trendelenburg–Fischer quarrel. He sided with Trendelenburg’s insistence that Kant’s arguments in the Transcendental Aesthetic do not strictly exclude the third possibility that space and time are both subjective and objective. His support did not spring from a desire to return to pre critical metaphysics. It reflected his historical scruple. He found in Kant an argument that established the a priori status of spatial and temporal form for appearances; he did not find a demonstration that barred all inquiry into their relation to things in themselves. Hence his refusal to follow Fischer in treating the second edition’s concessions as lapses to be erased. This stance drew a boundary between Zeller and both of the poles that defined the decade. Against speculative idealism, he rejected the collapse of form into content. Against positivism, he rejected the banishment of philosophy to the margins. The critical task as he understood it was neither to legislate being nor to repeat the procedures of the natural sciences, but to clarify the concepts through which any science is possible. That is why his histories of Greek philosophy mattered to the movement. They were not antiquarian catalogues. They were exercises in method, showing how whole vocabularies of explanation arise, harden, and are transformed. Zeller’s classical scholarship shaped his view of teleology as well. He was perfectly at home with purposive language in Aristotle. He was equally clear that the modern employment of purposiveness must be disciplined by Kant’s reflective judgement. The language of ends helps us to organise inquiry where mechanism runs short, especially in biology and in the philosophy of history. It does not license a jump to constitutive claims about the inner nature of things. On that point he parted company with Fischer’s final attempt to unify the system under freedom. The primacy of the practical can order the system without turning a practical postulate into theoretical knowledge. In Berlin from 1872 Zeller became the elder statesman of the learned critical attitude. Students remembered less the rhetoric than the method. He would take a famous thesis, detach it from its mythology, reconstruct the steps by which it had once seemed inevitable, and then show the limited range within which it still illuminates. In doing so he modelled a Kantian temper rather than preaching a doctrine. Philosophy earns its right to exist by that temper, by the patient distinction of questions of fact from questions of right, by the refusal to let either swallow the other. The parallels with Fischer remain instructive. Both were formed in the school of Hegel and Strauss. Both turned to Kant to save philosophy from obsolescence and to save religion from speculative appropriation. But where Fischer never ceased to hunger for a single metaphysical centre, Zeller accepted the discipline of plurality. He preferred an architectonic of standpoints to a doctrine of one substance. He was prepared to let some gulfs remain unbridged where the bridging would cost the very distinctions that make objectivity possible. This does not mean that Zeller’s Kantianism was narrow or merely defensive. His histories, precisely because they were histories, showed how concepts travel between the techno economic, political and cultural realms, and how confusions arise when a form proper to one realm is made to bear the content of another. That sensitivity would prove fertile for later neo Kantian currents. The Marburg emphasis on method in the exact sciences and the Southwestern emphasis on value and validity both owe something to Zeller’s refusal to turn critique into construction. What the story of Zeller and Fischer shows, taken together, is that the revival was never a single line. It was a field of tensions. One line sought unity in the idea of freedom and risks dissolving the critical boundaries. The other sought clarity in the distinctions of critique and risks loss of metaphysical warmth. The best work of the later schools would try to keep the gains of both. It would hold on to the primacy of the practical without converting it into knowledge of things in themselves. It would insist on the autonomy of science while refusing to reduce normativity to nature. In that sense Zeller’s legacy is methodological and moral. Do not allow a taste for system to outrun the evidence. Do not mistake the success of the natural sciences for a licence to dispense with critique. Above all, do not confuse the question what there is with the question how we are entitled to claim that we know it. Those maxims, patient and unfashionable, are the thread that runs from Königsberg through Heidelberg and Berlin to the schools that made Kant once again contemporary. Marburg, even though he had been warned that another storm was brewing. As soon as the conservative clergy learnt of Zeller’s appointment they were furious and organised protests. The theology faculty did all it could to block him, and Prince Friedrich Wilhelm refused to sign the papers. Only after a large protest in the liberal assembly did Zeller finally receive an appointment, although it was in philosophy rather than theology, and he accepted the condition that he would not teach theological topics. After the initial uproar he settled into life at Marburg, where he remained for thirteen years, from 1849 to 1862. He was not a popular lecturer, partly because his thick Swabian accent did not travel well. He found companionship in a circle of close friends, Wilhelm Giesebrecht in theology, Franz Theodor Waitz in philosophy, and Heinrich von Sybel in history, and this group became known as the Tuesday club. Zeller’s chief scholarly labour in these years was the second edition of his Philosophy of the Greeks, expanded from a single volume into three very large tomes. It was most likely during these Marburg years that he completed his quiet conversion from Hegel to Kant, for immediately after leaving Marburg in 1862 he proclaimed his Kantian convictions in his Heidelberg inaugural. We cannot reconstruct the precise moment of conversion. None of the published letters or writings from Marburg treat Kant’s or Hegel’s philosophy directly, and there are no student notes from his logic and metaphysics lectures. Still, it is very probable that a Kantian orientation had taken shape before he left. It follows that we must qualify the often repeated claim that Lange, who arrived at Marburg a decade later, was the father of Marburg Neo–Kantianism. Zeller closed his Marburg period when Heidelberg offered him an ordinary chair in 1862. Unlike the difficulties in Bern and Marburg, there was now no political controversy. The decade was calmer, and the chair lay in philosophy, not theology. In Heidelberg he soon moved within another distinguished circle, Robert Bunsen, Georg Jellinek, and Hermann Helmholtz. With Helmholtz he discussed his growing interest in psychology. Zeller’s return to Kant formed one of the milestones of the 1860s revival. His Heidelberg inaugural, delivered on 22 October 1862, mirrors in several respects Fischer’s Jena lectures of 1860. Like Fischer, Zeller judged German philosophy to be in crisis, and like Fischer he proposed a return to Kant and a redefinition of philosophy as theory of knowledge rather than as metaphysics. The fact that these messages were pronounced from two eminent platforms helped to shift the intellectual climate. The similarities invite the question of influence. Zeller knew of Fischer, and Fischer’s lectures had been in print since 1860. Yet there is no evidence that Zeller had read them, and the differences are revealing. Above all, they disagreed about the nature of the crisis. Fischer emphasised the threat of obsolescence from the rise of the special sciences. Zeller acknowledged that threat, but he stressed the vacuum left by the breakdown of the great idealist systems. Fischer still hoped to salvage something of that tradition. Zeller declared its decline final. German philosophy stands at a turning point, he said, because it is not possible to repair a Hegelian system that has broken beyond mending. If philosophy is to go forward, it must begin again from a new foundation. The best way to locate that foundation is to return to the point at which philosophy began before speculative Idealism, that is, to Kant’s Critique of Pure Reason. Kant marked a new beginning because he installed the theory of knowledge at the centre of philosophy. Others had pursued elements of such a theory, Locke and Leibniz most notably, but Kant made it thorough, comprehensive, and systematic. For Zeller, resurrecting epistemology was the remedy, the only way to diagnose why the great systems had failed. Zeller also offered a different genealogy of obsolescence. Fischer thought the special sciences threatened to usurp the role of philosophy. Zeller thought they had instead divorced themselves from philosophy. The relation had run off course because the sciences claimed to need no philosophy, and even feared its interference. He desired a symbiosis between philosophy and science, where each learns from the other, although he did not yet explain that symbiosis in detail. The most striking contrast concerned Hegel. When Fischer lectured, he still wrote within a Hegelian frame. Zeller renounced that frame as bankrupt. He began by declaring it a mistake to suppose with Hegel that logic has content, as if the forms of thought could determine the basic structure of being. Logic must be separated from metaphysics. It is purely formal. The forms of thinking are instruments for knowing things, and we cannot simply identify them with things themselves. Knowing and being are distinct. The foundation of logic lies with epistemology, not with metaphysics, since metaphysics, like any special science, presupposes methods whose validity epistemology must examine. Epistemology is therefore the first philosophy because we must investigate the origins and limits of knowledge before engaging in metaphysics. Even while urging a return to Kant, Zeller held that Kant made one fundamental mistake, an error so grave that it seeded the later errors of speculative Idealism. The mistake was the assertion of the unknowability of things in themselves. Kant argued that if the forms of our faculties condition what we know, then we cannot know how things exist apart from and prior to those forms. Zeller found a non sequitur here. Although the forms arise from us, it may still be that they conform to things in themselves. In holding open this possibility Zeller sided with Trendelenburg’s stronger realism. According to Trendelenburg, even if space and time are a priori, they may be true of things in themselves. Here Zeller diverged from Fischer. Without spelling it out, Zeller aligned with Trendelenburg in the dispute with Fischer that had begun in 1862. In Zeller’s view, truth in empirical science requires more than knowledge of appearances. We demand knowledge of things themselves. There is a hard realist element in his position, a transcendental realism, the identification of the objects of experience with a reality that exists independently of them. This realism appears when he argues against Kant that sensation does not furnish mere unstructured matter, leaving form wholly to ourselves, for the determinate spatial and temporal relations among particulars cannot be derived from the general forms of sensibility and understanding. Those relations are simply given. Zeller did not fear the old objection that we cannot step outside representation to check its correspondence with reality. Within experience, he said, we possess criteria. We compare representations of the same sense, of different senses, and of many perspectives. Only when they cohere do we ascribe reality. We also test by the laws of the empirical sciences, ascribing reality to a representation that conforms to those laws, and calling it illusory when it does not. Kant would have agreed that we do not need to step outside representation, and that such criteria suffice for empirical realism. He would have denied the further move that coherence plus lawfulness secures access to things in themselves. On Kant’s view that final step is a leap that no sceptic will grant. Fifteen years later Zeller revisited the problem in reflections added to the Heidelberg lecture. Now, under the influence of physiological psychology, he retreated from the earlier confidence. He extended the a priori to sensation itself, invoking the Müller experiments emphasised by Helmholtz. The quality of sensation depends on the specific properties of nerves and brain. Hence the content of a sensation cannot be reduced to the stimulus, and representation will not resemble its cause. Once he stressed the creative role of the senses, Zeller could no longer maintain that representations reflect things in themselves. We know directly only how things affect us and how we respond, and it is impossible to step outside this circle to grasp things as they are in themselves. The form and content of representation, the role of our activity and the role of stimulation, cannot be cleanly separated. Coherence among representations still functions as a criterion, but now it certifies only appearances. In this, Zeller joined Lange and Liebmann in conceding that the thing in itself, however awkward, is ineliminable. The core thesis of the 1862 lecture remains. The assumption of unknowable things in themselves created the difficulties that consumed the post–Kantian tradition. Fichte tried to explain the genesis of experience from the absolute I, but as Schelling soon observed, an absolute I is no subject at all once the meaning of subject is fixed by opposition to object. Schelling and Hegel then posited absolute identity, neither subject nor object but their unity, and attempted to derive the division between them. In doing so they left the field of experience and stepped into a transcendent metaphysics. One cannot begin from above with an abstract absolute, then derive concrete experience, for that is to extract content from form. The engine of dialectic stalls at the brink. It achieves the moment of negation but not a positive transformation. Zeller’s diagnosis of these failures supports his case that philosophy must begin with epistemology. It is necessary to examine the conditions and limits of knowledge before attempting to accumulate knowledge. Methods determine results, therefore the value of methods must be examined first. Knife grinders who never cut are an old target, and Hegel’s ridicule, Lichtenberg’s quip, and Diderot’s counsel still carry weight. Zeller did not answer those objections in the lecture. Yet within fifteen pages he offered the outline of a path out of the morass, and the outline mattered more than the proofs. One question remained unfinished. How exactly does epistemology prevent obsolescence at the hands of the special sciences. Zeller addressed this in a later Heidelberg lecture, delivered on 23 November 1868 for the birthday of Prince Karl Friedrich of Baden. He now described the threat in terms close to Fischer’s. After freeing itself from theology, philosophy resumed its ancient vocation as a general world view. The growth of the special sciences challenged that vocation. Each discipline now had its own domain and its own methods, which made it independent. Since reality had been parcelled out, philosophy seemed to have no subject matter left. Zeller picturing the poet who finds nothing left but the dream world of abstractions captured the worry neatly. What remains for philosophy depends on our epistemology. If we assume that there is a source of a priori knowledge independent of experience, we may define philosophy as the science of such knowledge, distinct from the special sciences that pursue only a posteriori knowledge. Zeller thought that this had been the idealist option, an a priori science that would construct reality by deduction. This had failed, he said, as the Hegelian method showed. Either it produced results that conflicted with experience, or else it smuggled in experiential premises. If, therefore, there is no independent a priori knowledge of reality, and if all knowledge in some way depends on experience, how do we distinguish philosophy from science. Zeller’s answer was that philosophy too must adopt an empirical orientation. That answer sharpened the problem. If method is shared, is philosophy redundant. Hence the urgency of the question. Zeller proposed three roles for philosophy. First, it serves as logic and epistemology. Thought is the same activity in all sciences, and it is philosophy’s task to determine the laws of that activity, which means the general conditions and forms of scientific thinking. Logic in this broad sense is theory of knowledge, a universal methodology. As such it cannot be redundant, since it investigates the foundation of all the sciences and so stands above their particular questions. Second, each special science employs basic concepts and presuppositions that it does not itself examine. To investigate those falls to philosophy. Physics uses matter, motion, space, yet it does not determine their exact meaning or whether they are ultimate realities or modes of appearance. Psychology uses the concept of mind yet does not determine its exact sense. For each discipline there will be a philosophy of that discipline, an inquiry into its presuppositions and elementary concepts. Third, there must be a science that studies the interconnections among the sciences, that transcends their boundaries and brings their results into a single view. Its task is the connection of all the sciences. Its subject matter is the infinite ground of being, which is to say metaphysics. Zeller did not wish to banish metaphysics as such. He wished to replace the speculative version with a metaphysics grounded in the methods and results of the special sciences. Thus philosophy still has much to do in a scientific age. It is logic and epistemology, it is critique of the presuppositions of each science, and it is a general metaphysics that synthesises the sciences. Zeller’s conception is traditional in that it preserves the idea of philosophy as a world view. Some of his Neo–Kantian contemporaries, Lange and Windelband among them, were ready to abandon that idea as archaic. The status of metaphysics remained a live question within Neo–Kantianism. Some sought to rehabilitate it with new methods, others called for its complete abandonment. Zeller also treated philosophy and the empirical sciences as continuous in method and discourse. Philosophy differs only in the breadth of its scope and in its second order perspective. Under Helmholtz’s influence, and in the line of Fries, Herbart, and Beneke, Zeller continued to see epistemology as a kind of empirical psychology. If philosophy is to become scientific, then epistemology must engage in experiment and observation within psychology and physiology. Ironically this pushed philosophy closer to obsolescence, for it made epistemology appear as psychology under another name, a point Windelband would soon press against him. In 1872 Adolf Trendelenburg died after nearly forty years in the Berlin chair of classical philosophy. The university saw only one candidate who could match his stature, Zeller. The offer of a full professorship came in July. To be called to Berlin was the crowning honour in nineteenth century German academic life, Berlin being the cultural centre of the new Reich, and its university having the most illustrious faculty. Zeller hesitated, worried about his age, now fifty eight, and about the energy that would be required. Helmholtz, on business for the government, travelled to Heidelberg to persuade him, and Zeller accepted, beginning his lectures in the winter semester of 1872. The outcast of the 1840s had become a celebrated figure in the 1870s. His politics had also moved with the times. He did not renounce his liberal principles, nor his advocacy of radical criticism, nor his loyalty to Strauss. Yet his convictions now aligned more closely with Prussia’s position in the new Reich. A Swabian by origin, he celebrated Prussian power, supported unification on the Prussian, that is, smaller German, plan, and supported Prussia in its war with France. In lectures of 1872 he defended the separation of church and state, which also spoke to the Kulturkampf. His convergence with the Prussian establishment reached its height in 1886 with a book celebrating Frederick the Great as a philosopher on the centenary of his death. For his Berlin inaugural in October 1872 Zeller returned to the theme of his Heidelberg lecture. He now voiced confidence that the identity crisis of philosophy was resolved. There is no danger of obsolescence, he said, because the German spirit will always seek reflection on the fundamental questions of life and examine the presuppositions of the sciences. The manner in which philosophy pursues those questions must be very different from the past. Instead of a priori deduction from first principles, it must investigate the conditions and limits of knowledge by empirical methods, through the observation and experiment of the new psychology. He had never been more explicit in his empiricism, and never clearer in his realism. We should comprehend things as they are, not impose our fantasies. Our philosophy should be realist, an image of reality. This empiricism and realism fit the temper of the age, with the advance of the sciences and the growth of technology and industry. In making a virtue out of following the Zeitgeist Zeller stood far from the radical critique of his youth. His most important Berlin writings on Kant were two substantial essays on moral philosophy, read to the Prussian Academy in 1879 and 1882. They complement one another and present a single outlook. Zeller sought a middle path between Kant’s formalism and hedonism. Kant had cast his ethics as the sole alternative to hedonism, either duty for its own sake or the relativism and egoism of pleasure. Zeller argued that there is a classical middle path, the humanist ethic of self realisation or excellence found in Plato and Aristotle. The advantage of such an ethic is that it anchors moral precepts in the general laws of human nature, which supplies content, yet aims at universality. In setting this view against Kant he followed Trendelenburg, and both represent a neoclassical standpoint in modern moral thought. The chief problem in Kant’s ethics, Zeller said, is formalism. Kant rightly saw that the moral worth of a maxim cannot be derived from its consequences. From this he wrongly inferred that experience cannot justify maxims at all. He therefore adopted a purely formal criterion, universalizability. The result is an empty criterion that can sanction almost any content. Once one has abstracted from all content one cannot mark the difference between right and wrong content by form alone. An egoist can universalise his maxim and be ready to live in a state of nature, to compete with others, and the formal test will not forbid it. If we are to give content to morality we must consider its purpose. Contrary to his own principles Kant does this often. When he asks us to universalise a maxim he invites us to consider what would happen if everyone acted in that way, which introduces consequences. When he formulates the kingdom of ends he expresses a teleological ideal. Hedonism is no alternative, for it collapses into relativism. People take pleasure in different things, as Plato already observed, so that only a very general rule would be possible. In both essays Zeller’s rejection of hedonism is unambiguous. It is a mistake to read him as affirming the simple principle that pleasure is good and pain is bad. That reading trades on equivocation about eudaimonism. Zeller distinguishes a hedonistic eudaimonism, which identifies happiness with pleasure, from a perfectionist eudaimonism, which identifies happiness with self realisation. He also distinguishes subjective from objective justification, where the former values actions as means to pleasure, and the latter values them for their own sake, taking pleasure in them because they are good. If Kantian formalism risks emptiness, and hedonism falls into relativism, how can universality be sustained. Zeller’s answer is to place the foundation of morality in psychology and anthropology, which determine the essential needs and common laws of human nature. What matters are the proper ends of human beings in virtue of their inner, law like constitution. This is Aristotelian in spirit, the enquiry into what is good for a human being as a human being. Engaging in characteristic activities brings pleasure, yet that pleasure is not the reason for action. There is plausibility in this position, and it is the natural move for the classicist, but it faces difficulties that Zeller did not confront. Appeals to human nature risk relativism, for human nature varies with culture and epoch, and conceptions of excellence may be incommensurable. Herder had already drawn that moral from history, and Nietzsche was publishing his relativist conclusions while Zeller addressed the Academy. Kant wisely avoided such appeals for just this reason. A second problem concerns normativity. If the normative is distinct from the factual, as Zeller also affirms against Schleiermacher, how do we derive norms from facts. Zeller saw the force of the problem and conceded that one cannot simply list common needs and call it a foundation. We need a criterion of valid needs, not only a catalogue of wants, but he offered no answer to the question on what that criterion rests. The Neo–Kantian debates of the 1870s and beyond would circle this problem, seeking a foundation for morality that meets the twin challenges of formalism and historicism. The rise and fall of reputations forms part of this story. One of the most controversial figures in Neo–Kantian history is Otto Liebmann, 1840 to 1912. Popular accounts have long cast him as the very founder of the movement, with Kant und die Epigonen of 1865 as its inaugural manifesto, and the refrain back to Kant as its summons. Recent scholarship has urged a drastic reassessment. Liebmann did not begin the movement. He followed earlier programmatic statements by Beneke, Helmholtz, Zeller, Vaihinger, and Fortlage. His interpretations can be crude and his polemic tendentious. It is unhelpful, however, to dismiss his philosophical work on account of his later politics. The value of his epistemology and metaphysics must be assessed on their own grounds. Moreover, the caricature of his politics is often inaccurate. A fair account of Neo–Kantianism must give Liebmann his due. He was among the first to see the problems with the psychological reading of Kant. He offered an early Neo–Kantian critique of positivism. He was also one of the few with the mathematical and scientific facility to discuss Kant in relation to new developments in those fields. He was a beloved teacher and influenced Windelband, Bruno Bauch, and Erich Adickes. His first book created a stir, and several later writings were widely read and favourably reviewed. He was also the best stylist among the Neo–Kantians. In a tradition not noted for elegance, Liebmann’s prose is urbane and witty without sacrificing rigour. Viewed broadly, Liebmann stands at the transition between two phases of Neo–Kantianism. The first interpreted Kant through psychology and physiology, a tendency that ran from the 1790s through the 1860s. The second emphasised epistemology and normativity and dominated the 1870s to 1890s. Liebmann shows marks of both. He believed that physiology could confirm parts of Kant’s epistemology, yet he stressed the sui generis status of the transcendental. His work contains a tension between physiological and epistemological readings of the Critique, a tension he struggled to resolve. In later years he stressed the epistemological side, sharply separating the normative question from the natural question, which anticipates Windelband and Cohen. From 1859 to 1864 Liebmann studied philosophy, mathematics, and natural science at Jena, Leipzig, and Halle. In Jena he learned from Karl Fortlage and Kuno Fischer, who decisively shaped his own programme. In Leipzig he attended Fechner and Drobisch, absorbing psychophysics and the mathematical approach to psychology. He habilitated at Tübingen in 1864, served a short military term in 1870, became extraordinary professor at Strasbourg in 1872 and ordinary professor in 1878, and returned to Jena in 1882 where he taught until his death. He did not produce a fixed system. He treated a complete system as an ideal approaches rather than something he could ever fully realise. He worked analytically and piecemeal and repeatedly stressed the provisional character of his conclusions. His development is most visible in his changing attitude to metaphysics. He began with an almost positivist contempt for the transcendent, and ended by defending metaphysics and acknowledging the value of the transcendent. Fear of materialism and aversion to positivism pushed him from a tough minded Neo–Kantianism, careless of moral value, toward a more tender minded Neo–Kantianism that gave moral value a place in the universe. Kant und die Epigonen made his reputation. It is a manifesto rather than a piece of Kant scholarship. The youthful author declared that Kant is the pivot of philosophy, and that every attempt to go beyond him has ended in failure. Fichte, Schelling, Hegel, Schopenhauer, Fries, and Herbart, all are epigones. The course for philosophy does not lie forwards beyond Kant but back to him. The style is emphatic and witty, sprinkled with multilingual quotation. Each chapter ends with the refrain we must go back. The title seems to belittle the successors, since epigone in modern German often means a derivative imitator. Liebmann probably intended the original Greek sense, those who come after. He is careful in the introduction to say that his epigones are independent thinkers and architects of their own systems, and he distances himself from Schopenhauer’s invective against Fichte and Hegel. The context of the book was the early 1860s. The text reads as a response to the Trendelenburg–Fischer dispute. As a student of Fischer, Liebmann would have wished to defend his teacher’s side. A critique of the thing in itself would undercut Trendelenburg’s third alternative. If there are no things in themselves, then the a priori forms of space and time hold only of appearances, and Fischer would win by default. Liebmann also wrote against the broader crisis of philosophy. Like Fischer and Zeller he lamented the diminished standing of philosophy. The public had grown indifferent, or been tempted by materialism. The source of the malaise he found less in obsolescence than in internecine strife. Oracles from Schelling were dismissed by Herbart, the boldness of Hegel was denounced by Schopenhauer, Fries attacked Fichte, Schelling, and Hegel, Herbart attacked Fries, Schopenhauer attacked them all. The picture is confusion. The remedy is the same as Zeller’s, return to fundamentals. If we know what in Kant is valid and what is ill judged, we have a criterion by which to weigh later systems. What is right in Kant, Liebmann said, are the central theses of the Copernican turn. The a priori forms of sensibility and understanding are necessary conditions of experience. Subject and object are interdependent. Knowledge is bounded by possible experience. Human representation is limited to space and time. The transcendental subject is an ineliminable condition. Showing these truths was Kant’s epoch making achievement. Yet a worm lies in the fruit, the postulate of the thing in itself. To say that there is a reality apart from and prior to cognition, and that it is unknowable in principle, contradicts the very restriction to possible experience that grounds Kant’s insight. If all that we can justifiably assert to exist lies within experience, how do we assert the existence of the thing in itself. Liebmann therefore demanded its expulsion. He thought Kant had raised it as a scarecrow to frighten rationalists from transgressing the bounds of experience. The scarecrow backfired, the epigones mistook it for a signpost. Armed with this diagnosis, Liebmann surveyed recent philosophy as so many doomed attempts to know the thing in itself. He found four directions. The idealist, which turned the thing in itself into the absolute, Fichte, Schelling, Hegel. The realist, which transformed it into simple real substances, Herbart. The empiricist, which treated it as a given material, Fries. The voluntarist, which made it the will, Schopenhauer. Defeating each reconfirmed the conclusion, there is no going beyond Kant. Liebmann’s most significant contribution in the book lay not in the arguments against the thing in itself, which are weak and often ignore Kant’s second edition preface, but in his critique of psychological interpretations of Kant. He attacked Schulze, Schopenhauer, and Fries for reading the Critique as empirical psychology. The a priori is not a cause or innate capacity, it is a logical condition for the truth of empirical judgements. The problem of the Critique is not the origin of our experience, it is the conditions of its validity. Nor can one derive the principles of knowledge by inner observation and induction, for such methods yield only what is particular and contingent, whereas the principles Kant seeks are synthetic a priori, universal and necessary. Transcendental philosophy is more than psychology because its business is to examine the very possibility of psychology. An empirical psychology presupposes the methods and principles that transcendental philosophy must investigate. In this, Liebmann anticipated later Neo–Kantian readings, although his book did not yet offer a full positive account of transcendental method. Liebmann himself soon called the book a youthful indiscretion. He came to see that Kant’s thing in itself is hard to avoid on Kant’s own premises, that the postulate has reasons in the economy of the system, and that Kant’s moral and religious concerns could not be brushed aside. Yet even the early polemic contained a moral motive. The Copernican revolution shows that man is the centre of his experiential world, and that the bounds of knowledge are immanent. That epistemological lesson contains an ethical lesson. We should make human problems central. All our problems are immanent, that is, they arise for beings who live in space and time, and we should strive to solve them here and now. Speculation about a transcendent realm distracts attention, and may also undermine the convictions on which moral responsibility depends, above all the belief in freedom. Kant had introduced the noumenal precisely to defend that belief against natural necessity, but Liebmann was convinced, for reasons we shall see, that this path leads into greater difficulty. Liebmann’s diagnosis that Kant’s strategy had misfired was meant to be therapeutic rather than iconoclastic. If the noumenal will erodes the very grounds of accountability, then freedom and responsibility must be secured within the only field where we experience them, the immanent order of causes and reasons. Hence the swift sequel of 1866, a polemical tract on individual responsibility and the freedom of the will. Its target was Schopenhauer’s hard determinism, together with the mystical exception he reserved for rare conversions of character. Liebmann grants the principle of sufficient reason and rejects the fiction of a will that can choose without grounds. What he will not grant is that the necessity of an action entails compulsion. He rebuilds freedom inside nature by distinguishing constraint from determination. I am unfree when I cannot do what I will. I am not unfree when my willing itself has causes, provided that in acting I still do what I resolve to do. On this basis he also restores the point of praise and blame. They belong to the practice that shapes character across time. We do not need to say that one and the same agent, with precisely the same character at the same instant, could do otherwise. We need only the familiar fact that character is educable and revisable, so that the next time, in the same outward circumstances, we may act differently because we have become different. Schopenhauer’s transcendental will is where Liebmann draws the line. If my intelligible character lies in an unknowable act outside time, then the conscious self has been removed from the source of its deeds, and the basis of responsibility is gone. The general lesson for Liebmann is clear. The postulate of a transcendental freedom does not rescue morality. It corrodes it. The remedy is a compatibilism that keeps the causality of nature and the authority of reasons together. Yet in closing his tract he reimports a Kantian thesis that sits badly with his stated aim. To be free is to be capable of acting morally. Freedom becomes a function of autonomy in the strict sense, the power to govern oneself by the moral law. This narrows freedom until wrongdoing becomes a sign of unfreedom. The power of choice that Liebmann wanted to honour is reduced to the power to choose well. Kant himself moved away from that early position. Liebmann, for a moment, did not, and so compromised his own project. He then tried to do what his first manifesto had not done, namely to argue positively for the critical standpoint using results from the new physiology of vision. The plan was simple. If sense qualities depend on the specific energies of nerves, and if the same stimulus can yield different sensations through different pathways, then the content of sensation belongs to the subject. Direct realism fails. From there he adds intellectual conditions. We project our inner affections as outer objects because the concepts of substance and cause govern experience as universal norms. The physiological chapters are brisk and confident, the epistemological chapter clear about the role of projection and hypostasis in everyday seeing. The difficulty comes when he asks after the ultimate conditions of this whole performance. Eyes, nerves and brain are themselves items in a world of appearances. They cannot be the last word in the explanation of experience because they belong to what must be explained. At this point the argument forces him to name what he had sworn to banish. There must be a subject that perceives and an object that affects it, neither of which is an appearance within the field they make possible. He tries to deny that these are things in themselves, but his list of their roles and attributes makes the denial ring hollow. He has rediscovered the boundary concepts of the critical system in the very attempt to dispense with them. A second difficulty also follows. If the transcendental conditions are not empirical, then no accumulation of empirical findings can establish them. The very appeal to physiology presupposes the framework it was supposed to prove. Liebmann had said as much against psychologism in his first book. He now had to say it against himself. War jolted his life and sharpened his convictions. The diary of the siege of Paris records pride in discipline and sacrifice and a brief attempt to read the spirit of the categorical imperative in the drill of an army. Taken in isolation, that passage encouraged the later caricature of Liebmann as a philosopher of obedience. Read alongside his own dialogue on New Year’s Eve, it has a different force. The ethic of subordination is episodic and defensive. It belongs to the posture of a citizen in arms. In peace, the state exists for persons, not the other way around. The same notes carry professions of cosmopolitan hope that are recognisably Kantian. He imagines an age after nationalism in which commerce, cost and the destructive power of weapons render war irrational, and in which the cultures of France and Germany complement rather than compete. He admired Prussia’s efficiency and the Kaiser’s role in unification, and he spoke harshly of France in the first edition. He later confessed that the harshness exceeded fairness, and retained it only as a record of a moment. The composite that emerges is a conservative liberal of his time. He values individual autonomy and a humane culture, distrusts levelling programmes, and holds that national loyalties and cosmopolitan law must be made to live together. The intellectual consequence of these years is a gradual shift away from the hope that the new sciences could ground the Critique, toward the thought that only an analysis of knowledge as such can do so. In the early writings he stands with Helmholtz, Müller and Fechner to show how physiology humbles naïve realism. In the later writings he turns back to the question that physiology cannot answer, the question of validity. He becomes a steady critic of positivism, not because he doubts the sciences, but because he denies that their methods can account for their own norms. The distinction between the natural question and the normative question becomes explicit. How we in fact form beliefs is one thing. What entitles us to call them knowledge is another. It is in drawing that line that he influences the next generation. Windelband will recast it as the difference between explaining and evaluating. Cohen will insist that the a priori is method, not psychology. Liebmann does not produce a finished system, but he reorients the debate. He also softens his early hostility to metaphysics. What he had dismissed as empty he now treats as unavoidable, provided it is understood as reflection on the presuppositions of inquiry rather than as construction of a world behind the world. He never fully solves the tension that marks his work. He wants to keep freedom and responsibility inside the causal order without trivialising either. He wants to secure the objectivity of science without returning to a realm of things utterly beyond knowledge. He wants to use empirical findings without confusing them with grounds of validity. The best of his later writing shows him holding these threads while refusing easy resolutions. The moral remains Kantian in spirit even where it criticises Kant. If we go back to Kant, we must go back to the problem Kant set, which is how knowledge and action can be both ours and bound by law. Liebmann’s appointment to Strasbourg in 1872, shortly after the war, gave him both security and a public stage. The annexation of Alsace Lorraine had made Strasbourg a German university again, and the authorities wanted to display the intellectual seriousness of the new Reich. Liebmann became extraordinary professor of philosophy and stayed for the next decade, founding the tradition that later drew Windelband, Rickert and Lask to the region. In the 1870s he returned to the problem that had haunted his earlier work, the relation between natural science and transcendental philosophy. His first attempt to bring physiology and epistemology into dialogue had collapsed under its own contradictions. He had demonstrated the thing in itself when he meant to refute it, and refuted the physiological relevance he had meant to establish. Yet he persisted, convinced that the question was not whether the sciences were relevant to philosophy but how and in what respects they were. The relation was too intricate and too fluid for a single verdict of relevance or irrelevance. What was needed was analysis in detail, patient work from particular problems upward. The outcome was On the Analysis of Reality, first published in 1876. In this book Liebmann’s thought reached maturity. The manifest weaknesses of his earlier writings had taught him caution. He abandoned grand pronouncements and replaced them with analytic precision. Philosophy, he now argued, must begin with the particular and advance to the general, not the other way round. Any system would have to remain a distant goal, a guiding ideal rather than an achievable structure. On the Analysis of Reality became his most respected work, went through four editions, and won praise even from those who disagreed with him. Windelband called it one of the most distinctive works ever to express a philosopher’s worldview, each chapter an independent study that revealed its place in a larger living whole. Liebmann was unusually well equipped to discuss the relation between philosophy and the natural sciences. Trained first in mathematics and physics, he could handle technical material with clarity and economy. His discussions were lucid and exact, though limited by the state of the sciences in the 1870s. He wrote after the emergence of non Euclidean geometry, Darwin’s theory of evolution, and the physiological psychology of Fechner, Weber and Helmholtz, but before the revolutions of relativity and quantum theory. The essays remain valuable because they show how Neo Kantianism tried to evolve with empirical research rather than oppose it. Three essays re examine the psychology of vision that had occupied him before. The central question is whether Kant’s thesis of the phenomenal character of space can be confirmed by empirical science. Phenomenal here means relative to our sensibility, existing only in and for consciousness. Liebmann still thought the evidence supported Kant. He drew on the theory of specific nerve energies to argue that the quality of sensation lies in the organ, not in the object, and with Helmholtz he held that spatial form is an intellectual construction arising from the organisation of visual and tactile data. What we see are optical phenomena, not things in themselves. Visual space is projected by the understanding, a construction coordinated from sensory material. He described in detail the act of projection. We take ourselves as the centre of a coordinate system and assign our sensations to definite places left and right, above and below, before and behind. From these placements we construct a three dimensional world whose centre is the perceiving subject. Space is therefore an intellectual structure that the mind generates in locating and ordering its sensations. The visible world from our bodies to the stars is not an absolute external reality but a phenomenon within our sensibility. Two further essays consider whether space, time and motion are absolute or relative. Here Liebmann defended what soon seemed an outdated thesis, that physics presupposes absolute space and absolute time. He argued that axioms about temporal continuity and succession require an absolute time, and that Newton’s law of inertia and the example of rotation in empty space require an absolute spatial framework. He conceded that all empirical measures are relative, yet maintained that science depends conceptually on the ideas of absolute space and time. His most original essay, Space, Characteristic and Deduction, examined Kant’s theory of space in light of the new geometries of Gauss, Riemann and Lobachevsky. At first sight non Euclidean geometry might seem to refute Kant by showing that Euclidean space is only one among many logical possibilities. Liebmann argued instead that it confirms Kant. The new geometry constructs the possibility of many kinds of space by varying the number of coordinates in an analytic system. This does not contradict Kant, who never claimed that Euclidean space was the only possible space. He claimed only that our form of intuition is Euclidean. Other beings with different sensibilities might perceive through other geometries. To make sense of this, Liebmann distinguished logical from intuitive necessity. The axioms of geometry are not logically necessary, since other consistent systems exist, but they are intuitively necessary for us, because we cannot imagine space otherwise. The transcendental aesthetic therefore retains its force. Euclidean space is necessary and universal only for beings with our sensibility. Liebmann’s training in mathematics made him a passionate defender of the mathematical sciences against the speculative philosophy of nature of Schelling and Hegel. In On the Analysis of Reality he offered a blunt apology for the method of mathematical natural science. Nature, he argued, is fundamentally quantitative. Every being has its precise measure and magnitude, and its individuality consists in that quantitative determination. Without it, things would dissolve into nothing. The philosophy of nature, by neglecting mathematics, condemned itself to vagueness. Reason in the universe is not a world spirit or a cosmic will. It is the lawful order of quantitative relations expressed in natural laws. Yet this did not lead him to crude materialism. The more he distanced himself from positivism, the more he found himself drawn back toward the older conception of nature as purposive, self organising and rational, a conception he had once rejected as mystical. Like many Neo Kantians, Liebmann fought his philosophical battles in the shadow of the materialism controversy of the eighteen fifties. Materialism appeared to him as the chief intellectual and moral threat of the age, an account of mind that reduced thought to secretion. In On the Analysis of Reality he at last confronted it directly. He surprised his earlier self by granting much that he had formerly denied. The evidence, he now admitted, shows beyond doubt that the brain is the organ of thought and that mental activity depends on brain activity. A programme of empirical materialism, aimed at mapping exact correlations between brain events and mental sequences, is legitimate and indispensable. Yet correlation proves nothing about the nature of consciousness. However far we extend it, there remains a gulf in kind between chemical order and logical order. A change in molecular configuration can correspond to a change in thought, but it cannot explain why one sequence of thoughts is rational and another absurd. To imagine that it could is to mistake correspondence for causation. Even perfect physiological knowledge would leave the problem untouched. If reason is a product of nature, then nature must already be rational in its structure. A brain capable of logic must itself be organised according to logical principles. This conclusion drew him close to the teleological philosophies he had earlier condemned. In later essays he declared that the old opposition between mechanism and teleology was obsolete. Mechanism is the means by which teleology achieves its ends. Nature’s lawful regularity does not exclude purpose. It is the very condition under which purposes are realised. He even argued, using a probabilistic analogy drawn from Laplace, that the harmony of natural laws is too improbable to be the result of chance and must have a common cause, a rational design. Here he moved beyond Kant’s strictures, treating teleology not as a guiding rule for inquiry but as a truth about the world. He admitted that this broke the letter of the Critique, yet he justified himself by noting that Kant himself had overstepped his own limits when he treated the thing in itself as the cause of experience. If Kant could do so, why should his successors not follow him. This line of thought led Liebmann away from positivism. His earlier admiration for the exact sciences gave way to a more critical appraisal. Science is indispensable but insufficient. It cannot solve philosophical problems because it presupposes the normative structures that only philosophy can analyse. Human beings are both products and conditions of nature. Any account that treats them as mere effects of natural processes is incomplete. His later writings, culminating in The Climax of Theories of 1884, were directed against the new positivism of Richard Avenarius and his school. Avenarius had proposed to purify experience of all metaphysical residues, reducing it to a neutral field of given data. Liebmann countered that such pure experience is a chimera. Experience without the organising principles of the understanding would be a blur of sensations. The a priori principles of identity, continuity and causality are not derived from experience but are conditions that make experience possible. Any attempt to remove them abolishes intelligibility itself. In the first six chapters of The Climax of Theories Liebmann seemed to follow the positivist classification of scientific explanation into three levels, empirical, hypothetical and metaphysical. In the final chapter he overturned the scheme. There is no such thing as a theory that rests purely on experience. Every theory presupposes transcendental principles. Positivism, in ignoring this, is itself a naive metaphysics. It hides its assumptions rather than examines them. The task of philosophy is to make those assumptions explicit and to show how the sciences depend on them. Through this long struggle with science, materialism and positivism, Liebmann clarified what transcendental philosophy must be. In the eighteen sixties he had vacillated between psychology and epistemology. By the eighteen seventies he saw that transcendental philosophy concerns not the empirical causes of knowledge but its normative grounds. In The Metamorphosis of the A Priori of 1876 he explained that Kant had transformed the Leibnizian notion of innate ideas into an epistemological one. The a priori is not an inborn content of the mind but the set of forms and norms that make cognition possible. These forms are not merely subjective. They have what Liebmann called a meta cosmic status. They govern both subject and object, the whole field within which experience takes place. This, he said, was the true revolution of the critical philosophy. Kant turned Leibniz upside down, making the a priori the basis of the subject rather than the other way round. He also distinguished carefully between the transcendental and the psychological senses of the a priori. The one concerns epistemic norms, the other natural laws of mental operation. Both are legitimate, but they must not be confused. The transcendental principles prescribe how knowledge must proceed if it is to be valid. The psychological laws describe how thinking in fact occurs, whether valid or not. In this distinction Liebmann anticipated the later Neo Kantian separation of the question of fact from the question of right. His final statements, especially On Transcendental Philosophy of 1901, gave explicit priority to the epistemological standpoint. The business of transcendental philosophy is to determine the universal conditions of knowledge, not to investigate the empirical psychology of knowing. Its key principles, identity, causality and continuity, are interpolative rules that add structure to experience. They cannot be justified by experience but only by showing that without them knowledge would be impossible. Their justification, Liebmann suggested, is pragmatic and teleological. They are valid because they are necessary means to the end of attaining knowledge. In these late writings Liebmann still resisted the temptation of objective idealism. The transcendental principles are preconditions of the world for us, not descriptions of things as they are in themselves. Yet he also acknowledged that the transcendental subject, the I think that unifies experience, is impersonal and unknowable, existing equally in all finite knowers. Each personal consciousness participates in this universal self, as a copy participates in its archetype. In this figure, the thing in itself, which he had once tried to expel, returned transformed. It no longer meant an unknowable object outside experience but the unknowable ground of the knowing subject. While Cohen and Windelband were eliminating the concept, Liebmann restored it in a new key. The last phase of his work, Outline of a Critical Metaphysics of 1901, made explicit what had long been implicit. Having defended the legitimacy of metaphysics, he now attempted to construct one. It was to be critical and immanent, not speculative, yet it ventured beyond mere agnosticism. He addressed the classical questions, the relation of mind and body, the one and the many, mechanism and teleology, and sought to show both their limits and their necessity. He insisted that metaphysics arises from a natural and legitimate need of reason, the need to ask why, and that to forbid that question is itself dogmatic. Against the positivists he defended a reformed Platonism, the permanence of form amid change, the law as the enduring structure of flux, the teleological organisation of life. For Liebmann, the Platonic idea had become the natural law, the rational pattern that governs the evolution of kinds. The laws of nature are expressions of forms, and the forms themselves are ends. Teleology and mechanism are partners. Mechanism is the instrument by which purposive form realises itself. Even if science were to achieve a complete mechanical account of life, teleology would not disappear, because the intelligibility of mechanism already presupposes order and purpose. The dogmatic system builder of the eighteen sixties had become, by the turn of the century, a chastened but still metaphysical thinker, one who had learned that the limit of knowledge is not the end of reason but its proper beginning. Liebmann’s doubts about psychophysical parallelism go far beyond a polite warning that it is only a hypothesis. On his account, some central features of mental life can never be captured by any one to one mapping from brain to mind. There is no physical counterpart for the unity of the self, which is a precondition of experience rather than an item within it. Earlier, in his essay on mind and brain in On the Analysis of Reality, he had conceded for the sake of argument that an exact correlation might in principle be found between neural events and thoughts, and he had then inferred from such a correlation that nature must possess an inherent rationality great enough to build a thinking machine. In the Outline of a Critical Metaphysics he withdraws that concessive strategy. The naturalist cannot bridge the divide between the natural and the normative. Brain events are governed by natural laws. Thinking is governed by norms. The gap between what is and what ought to guide our inferences is as deep as the distinction between fact and standard. Normative laws presuppose a freedom of intellect, the real possibility of failing to follow them, just as moral laws presuppose the real possibility of acting otherwise. What neural event could correspond to that counterfactual space in which we acknowledge that we might have reasoned more carefully, or might have drawn the right conclusion rather than the wrong one. The transcendent bent of Liebmann’s later thought is clearest in his treatment of the ancient problem of the one and the many. Why is nature so pervasively regular. Why do lawful patterns hold, and why can we unify laws under still more general laws. Reviving the probabilistic analogy he had sketched in The Order of Nature, he argues that the probability of a single ground for the order of the world is overwhelming. The inference is indeed transcendent, since it generalises from order within nature to a common cause of nature as a whole. Liebmann accepts the charge, and replies that Kant himself had already crossed that line by treating the thing in itself as the cause of experience. With this, he frankly admits that a strictly immanent metaphysics cannot be maintained. His position is even less guarded when he considers the source of consciousness. He repeats that the source is wholly unknowable, since every act of awareness, even self awareness, divides into knower and known. The unity that grounds both cannot be an object for us. Having marked that limit, he then gestures toward a way round it. He opens the door to mysticism by pointing to a psychological analogue of the primal unity, dreamless sleep. In that state, consciousness lapses and subject becomes one with object, as if returning to the source of all awareness. He salutes the Upanishads and Vedānta for cultivating an insight into that unity that has no equal on earth. Whatever its spiritual value, this is no longer a Kantian posture. For Kant, the limits of discursive thinking are the limits of thinking as such, and mysticism is only an evasion of the difficulties of concept and argument. Nowhere does Liebmann depart further from the spirit of critical philosophy than in this late flirtation with mystical union. The arc of his development is complete. The defender of immanence acquires the urge to overstep it, and chooses the most extravagant means. Jürgen Bona Meyer typifies a different branch of the generation that came of age in the eighteen sixties. He is the least known among them, but he mattered to the revival. His essays in the materialism controversy were among the most subtle, and his book On the Struggle over Life and Soul of eighteen fifty six appeared before the manifestos of Fischer, Zeller and Liebmann. In the eighteen seventies he contributed to the Neo Kantian debates on Schopenhauer and Darwin. Two books earned him a place of his own. Kant’s Psychologism was the last and strongest statement of the psychological reading of Kant. Questions of the Times was an early and ambitious attempt to sketch a Neo Kantian worldview. He was also the first in the movement to raise the themes that the South Western school would later develop under the heading of the philosophy of history. The facts of his life are sparse but clear. Born in Hamburg in eighteen twenty nine to a prosperous family, educated at the Johanneum, he began with medicine and the natural sciences at Bonn, then shifted to philosophy in Berlin, working with Trendelenburg and writing on Aristotle’s biology. He contributed to the Academy’s Aristotle index, and for a while seemed set on a classical career that Trendelenburg encouraged. A year in Paris widened his horizon. He learned French, absorbed Voltaire and Rousseau, and returned to Hamburg as a private tutor who also threw himself into civic life, helping to found an art museum, a Schiller memorial, a public library and a school for business education, and co editing a popular paper. Academic security came with a habilitation in Berlin in eighteen sixty two and a lectureship at the teachers’ academy. By the late sixties he was appointed to Bonn, where he remained, becoming a popular teacher, rector of the university, and an energetic organiser of adult education in the Rhineland. In the late eighteen eighties and early nineties he drifted from Kantian dualism toward monism, but a stroke in eighteen ninety five ended the project of a final book. He died in Bonn in eighteen ninety seven. Meyer’s hallmark was a resolutely critical reading of Kant. The critical philosophy is not a metaphysics and not a new idealism that opposes materialism. It is a doctrine of limits that stands above such disputes. He belonged to the psychological line that ran from Fries and shaped Helmholtz’s approach to perception, and he did not share the later doubts of Fischer and Liebmann about psychologism. His ambition, often described as Enlightenment renewed, was to unite science and popular education. He placed himself in the tradition of Kant and Voltaire, and defended the liberal ideals of tolerance, freedom of conscience and the separation of church and state. That public spirit informed even his philosophy. The materialism controversy of the eighteen fifties was his crucible. He was present at the infamous meeting of the German naturalists and physicians in Göttingen in eighteen fifty four, heard Wagner’s moral thunder and Vogt’s provocation, and was appalled by the intolerance on both sides. The spectacle reminded him of Voltaire’s satire on metaphysicians who claim much and know little. From that disaffection came his sceptical Neo Kantianism. Unlike Fischer and Zeller, who feared the eclipse of philosophy by science, Meyer’s fear was the endless, undecidable quarrel of metaphysical schools. The critical philosophy, he thought, could show why the dispute between idealism and materialism has no rational settlement. The task was to refound critique as a doctrine of boundaries. He set out this position in his Hamburg lectures of eighteen fifty six, published as On the Struggle over Life and Soul and followed by two series of articles. Kant’s standpoint is neutral. Both materialism and idealism talk about reality in itself and therefore exceed the limits of possible experience. Neither can be demonstrated and neither refuted. They stand as hypotheses about things in themselves. On theoretical grounds there is no decision to be had. He then examined, with patience rather than polemic, the failures of demonstration on both sides. The materialists explained life and mind by the laws of matter, but could not say why the initial conditions conspire to yield just those combinations that produce life and thought. The idealists insisted on plan and purpose, but could not explain how ideas bring themselves into material existence. The proper lesson is modesty and tolerance. Meyer admitted a personal preference for idealism, but only as an avowal without theoretical force. He invoked Kant’s gesture in the Spirit Seer where, after delimiting knowledge, he allows himself a belief that sustains hope. Here, however, his reading of Kant is selective. Kant is not as neutral as Meyer supposes. He claims that materialism is false, both because matter is appearance and not thing in itself, and because apperception shows the self to be simple and therefore not in space. Kant also claims that the mind body problem can be resolved when both sides are understood as forms of representation within a unified experience. Meyer could reply that these claims do not follow from the Critique. Space and time might still correspond to things in themselves. Yet Meyer himself took Fischer’s side against Trendelenburg on that very question, which made his neutral reading harder to sustain. A second point of tension concerns faith. Kant denied knowledge to make room for a rational faith grounded in the moral law. Meyer wished to open the field to personal conviction as such, welcoming precisely the idiosyncratic beliefs that Kant meant to exclude. He criticised the attempt to provide a practical proof of God and immortality and treated the practical sphere as one of choice without demonstration. Kant’s Psychologism of eighteen seventy was the last major defence of a psychological foundation for critique. Meyer asks what role psychology plays in transcendental philosophy, how we know the a priori, and why Kant later minimised psychology. Against Fischer and Liebmann he argues that discovery and justification must be distinguished. The a priori is not justified by self observation, but it can be found through it. The method is reflective, analytic and abstractive. He reads Kant’s early prize essay on method as evidence that the critical procedure parallels the natural sciences. He concedes that Kant himself drew a sharp line between the question of right and the question of fact, but he insists that psychology is necessary for discovery even if not for proof. Here his case wavers. He sometimes acknowledges that justification is logical rather than psychological. At other times he claims that once psychology is broadened to include reflection and abstraction it can supply both discovery and proof. In so doing he collapses the very difference that later Neo Kantians would make central, namely that transcendental deduction establishes validity, not empirical genesis. The same reduction shapes his treatment of logic. Kant separates logic from psychology. Logic sets norms for how we ought to think. Psychology describes how we do in fact think. Meyer replies that we learn the rules of inference by observing good reasoning, just as we learn grammar by observing the language of native speakers. He thereby treats logical necessity as grounded in human nature and brings logic close to Friesian anthropology. He defends Kant’s psychology against Herbart’s influential critique. Herbart had attacked faculties as relics of rationalism. Meyer replies that a faculty names a genuine primitive class of effects, and that one and the same soul can act in distinct characteristic ways without forfeiting its unity. He then argues that Kant’s threefold division into representation, feeling and desire is truer to experience than Herbart’s reduction of everything to representation. Feeling is not mere sensation because it involves valuation. Desire is not mere striving of ideas because it includes the sense of need and possession. Representation is not reducible to either because we often perceive without caring or wanting. Introspection, while fallible, is indispensable if used with the same care we demand in astronomical observation. On this basis Meyer concludes that Kant’s psychology gives critique its proper foundation, and that Kant’s refusal to acknowledge that foundation led to a sterile formalism in logic and ethics. The judgment was bold, and by the end of the decade already sounded old fashioned. Within a few years Cohen and Windelband would install epistemology where Meyer had placed psychology. Questions of the Times, his major book of eighteen seventy, is a wide ranging and finely argued work. It surveys the condition of philosophy, the literature on the mind body problem, the claims of Darwinism, and the situation of religion. It is learned and accessible, shaped by the Enlightenment aim of bringing science to the public. Like his contemporaries, Meyer worried about the obsolescence of philosophy after the collapse of the grand systems. The sciences had freed themselves and prospered on their own methods. The dream of grounding them from above had faded. The dream of knowing the absolute had likewise failed, because it ignored Kant’s lesson that philosophy belongs in the depths of experience. What then should philosophy be. Meyer’s answer has two parts. First, it should become psychology, meaning a reflective study of mind as such rather than an aggregation of special sciences. This subsumes epistemology within psychology and blurs Kant’s distinction between the question of fact and the question of right. The cost is that philosophy risks dissolving into science. Second, he re admits metaphysics, not as knowledge of the unconditioned but as the attempt to form a general view of the world that brings mind and body into ordered relation, corrects dogmatism and sustains discussion. He also defends free will. He aims to show only its possibility, which is all that critical limits allow. Freedom for him means both the power of choice among alternatives and the power to act on what we judge right. It is not identical with mere self determination by one’s own nature, since it includes the power to do otherwise. The main evidence is the ordinary consciousness of responsibility. Determinists can challenge that evidence, but they cannot disprove it. If argument will not move them, the defender of freedom will quietly drop anchor in the harbour of immediate self awareness. Schopenhauer is the chief opponent here. Meyer grants that every action has a motive, but denies that motives determine us independently of our deliberation. Choice determines which motive is effective, not the other way round, and our character is not an unalterable datum. Most of us struggle, hesitate and form a second nature through resolve and habit. Schopenhauer’s examples of criminals who say they would act the same way again prove little. Their plea for punishment expresses precisely the conviction that they could have done otherwise. As for Schopenhauer’s primal intelligible act that fixes our character, Meyer deems it irrelevant to responsibility, since it is unknowable by the very terms of the system. He is no less severe on Kant’s identification of freedom with the rational will. If only the moral will is free, then immoral action is unfree, which empties responsibility of content. Kant writes as if sensible and rational natures are given in fixed strength, whereas freedom requires that we can shape our nature. Yet Meyer does not face the hard consequence of his own view. If the will acts within the realm of nature, how does it escape determination by natural law. The fundamental problem returns. Finally he confronts the theological challenge. Is human freedom compatible with divine omniscience and omnipotence. He lays down a rule of method. Begin from human experience, not from speculative doctrines of the divine. The certainty of experience should not be sacrificed to the uncertainty of metaphysics. Since our experience as agents presents freedom as an unavoidable datum, any theology that denies it must give way. On that basis he rejects pantheism, taking aim at David Friedrich Strauss. If God is identical with the world, and divine necessity is part of ourselves, the experience of choice vanishes. With pantheism set aside, he concludes that only theism remains as a framework within which genuine freedom can be made sense of. Theism, which distinguishes God from the world, can be made compatible with the human awareness of freedom. This still leaves the choice among forms of theism. How should we conceive the divine attributes and the relation between God and the world if human freedom is to stand. Divine omnipotence is the first obstacle. If God creates and sustains everything, how do human beings act on their own. Would our freedom not limit divine power. Meyer answers by drawing a boundary. God’s action is required to create and sustain the essence or being of things, but not to determine their particular actions. We must distinguish essence from act. Only essence requires the creative and preservative powers of the divine. As a free agent, God has created other free agents in his image and has provided all that is required for the exercise of their freedom. When human beings use the freedom God has given, this is not a limit upon omnipotence but a manifestation of it. Divine foreknowledge is the second obstacle. If God knows all truths, he knows our future actions. If he knows them, they seem fixed, and our freedom seems lost. Meyer canvasses three lines of reply. Foreknowledge might extend only to necessary truths and not to contingent choices. It might remain perfect even if it does not include future free actions. It might be eternal and so not belong to the temporal order in which human actions occur. He recognises the cost in each case, for each limits omniscience in some respect. He does not choose among them, leaving the reader on the brink. Whatever their merits, the reflections raise a worry about his own critical boundaries. His defence is that he does not claim knowledge of God, only an account of what God must be like if human freedom is possible, and so the whole inquiry is hypothetical. In adopting the rule that an account of God must be based upon the datum of freedom, he follows something close to Kant’s doctrine of practical faith, which grounds religious belief in morality and ultimately in the experience of freedom. Yet here too a tension appears. Meyer had been severe on Kant’s attempts to demonstrate God and immortality through practical reason. He had wanted faith to remain a matter of personal conviction. His own reflections, however, are not offered as private fancy but as demonstrations of what must be so if certain assumptions hold, including the existence of God and of immortality, and they begin from facts of moral consciousness. One of Meyer’s aims was to renew the philosophy of religion, which had declined since the flowering of Tübingen and Hegel. This aim is plain in the long chapter on religion in Questions of the Times. He diagnoses a stifling indifference to religion in German life, both among the public and among philosophers. Religion is treated as the business of clergy or as a private matter of conscience. The causes may be the spread of materialism, the discredit of philosophy, or the practical temper of the time. Whatever the cause, indifference cannot last. Writing at the close of the eighteen sixties, he has in mind the new conditions of the Second Reich, which had drawn Catholics and Protestants into one state. How could a single nation be both. What was the loyalty of Catholics to a Protestant Prussian state. The forces behind the Kulturkampf were already forming. To sort out such issues, Meyer calls for a revival of philosophy of religion, the only discipline that can address the most general questions at the root of the disputes, above all the relations between reason and faith and between God and world. He also attacks two old prejudices. The first is the claim that the ideas of the learned must be kept separate from the faith of the people. That division, found in debates from Lessing to Kant, no longer suits a more educated age in which everyone wishes to think for himself. As he puts it, we have given up distributing the right to seek truth by rank or profession. The second is the claim that religion is purely private. Religion is not only feeling but thinking. It makes claims to truth, and only open discussion can test them. Because religion now belongs to the public sphere and cannot be confined to privacy, philosophers should help create and sustain that discussion. Adapting Plato, he writes that the religious life of a nation will improve only if religious teachers become philosophers or philosophers become religious teachers. He insists, in a critical vein that goes back to the eighteen fifties, that philosophy has no objective criterion by which to prove or refute articles of faith. It can clarify controversies, assess arguments on particular points and define the limits of knowledge. Beyond this critical office he assigns a constructive task. Philosophy must show systematically how religion arises from human nature. Against the materialists, who regard religion as a dispensable superstition, a religious anthropology should show that religion is a constant feature of human culture because it meets basic needs that cannot be eradicated. The common element behind all religion is the feeling of dependence on higher powers and the need to honour them. This anthropology is frankly apologetic. Its purpose, as he says, is to say the right word on behalf of faith. Although reason cannot demonstrate the existence of God, Providence or immortality, experience can still help us judge which religion best suits our needs. This provides a kind of transcendental deduction of religion. We justify belief not by syllogism but by tracing it to its roots in our nature. Since we cannot get beyond our nature, the objective truth of religion remains undecidable. Yet it is our nature that provides the ultimate test of the worth of any religion. Meyer sketches a basis for such an anthropology. Religion arises from all sides of human nature, from thinking, willing and feeling. It involves thinking because it aims to comprehend the whole and to see the finite as part of the infinite. It concerns willing because it lays down precepts and prescribes action. It consists in feeling because it is a sense for the infinite present in the finite. He faults Kant, Hegel, Schleiermacher and Fries for one sidedness. Kant reduced religion to moral duty and made its concern with the whole superfluous. Schleiermacher and Fries rightly stressed feeling but neglected its dependence on thinking, for the sense of the infinite within the finite arises as thinking strains to go beyond sense. Hegel corrected Schleiermacher’s excess but went too far in the other direction by overstating the role of thought. A proper anthropology will justify religion by showing how it answers to all three sides of our nature. The chapter on religion most clearly displays his project of restoring the Enlightenment. He repeatedly pleads for a rehabilitation of natural religion. He does not wish to revive the old proofs of God and immortality, yet his anthropology still intends to show that religion is lodged in human nature. Even if we cannot find religion in external nature, as the deists once hoped, we can still find it within. Religion would then have a universal sanction that rises above local custom. He stresses that one value of such an anthropology is to move past the sectarian quarrels of the time by identifying a core shared by Protestant, Catholic and Jew. This would reveal a broad invisible Church and would restore tolerance, which is the first rule of all honest controversy. The latitudinarian spirit of the early Enlightenment is his guide, and his great model is Voltaire, whom he admires for scepticism toward controversy and revelation, for insistence on reason in religion and above all for tolerance. That spirit lies behind the attempt to reinstall Enlightenment ideals, which inspires the book as a whole. Meyer also made an early foray into the philosophy of history. A weakness of Neo Kantian writing in the eighteen sixties was its silence about history, despite its pride in close engagement with the empirical sciences. While the movement discussed physics and physiology with zeal, it neglected a field that had advanced quickly since the early century and that had made strong claims to scientific standing. The new critical history of Ranke and Niebuhr and the historical school of law of Savigny and Eichhorn had already set methods for sources, testimony and inference. Here was fertile ground, and the questions pressed in. What are the methods and standards of history. How do they differ from those of the natural sciences. What do we mean by science, and how does history meet that meaning. The movement would not take up these questions until the eighteen eighties and nineties, when Dilthey in Berlin and then Windelband, Rickert and Lask in the south west made the logic of history central. It is therefore striking that Meyer wrote a major article on the philosophy of history in eighteen seventy one, published in an historical journal. It surveys recent work by Lotze, Buckle, Mill and others, but it also states his own view. He answers two questions. Is a philosophy of history possible. What is its relation to history itself. He replies that a philosophy of history is possible, though recent efforts have offered only programmes and no execution. He gives the phrase a naturalistic sense. The philosophy of history should determine scientific laws of human conduct, that is, causal relations between persons and their natural and social environments. It should not begin by announcing the purposes of history. A teleological account, if any, should follow only after the empirical laws of conduct are known. Speculative idealism erred in laying down ends a priori and then scouring experience for confirmation. Confidence that a philosophy of history is possible rests on confidence in psychology. If psychology can be a science, then a history built on it can be a science. Psychology, he thinks, can proceed by observation and experiment, and Kant’s doubts only reflect an ill suited deductive ideal of science. General laws of action can then be applied to particular cases, yielding more specific laws that belong to history itself. His history here borders on anthropology, on what Mill called ethology, and on projects in folk psychology. Kant is again the model. The essay Idea for a universal history provides the thread. Amid the chaos of individual choices, there is lawlike development. Human powers tend to unfold, and not only in individuals but in the species. History thus rests on psychology. Yet Meyer also sees that history is more complex. He argues against Mill that psychology is not the whole of it. Nations and states are historical structures with a development that cannot be reduced to individual psychology. They have their own logic and require a distinct science, provided it remains causal and empirical. He also notes that the individual cannot be understood in isolation but only in social and historical context. Psychology alone cannot answer whether morality, aesthetics and logic are innate or acquired. To answer such questions, we must look at the whole of history. He does not, however, pursue the further question of how a broader, non psychological history is possible. On the relation between philosophy of history and history, he describes a life and death struggle. Each claims the title of science. History charges philosophy with generalising on too few facts. Philosophy scorns history as a mere recital of particulars that never reaches law. The critical philosopher should reconcile the parties by stressing interdependence. Theory is empty without facts and narrative is blind without causal analysis and diagnosis. He affirms the possibility of a general philosophy of history but denies that it alone enjoys scientific status. He defends the scientific standing of history in its own right against Mill, Buckle and Lazarus, who make general law the condition of science. Even when it confines itself to particular structures in a particular time and place, history can be scientific. Its results can be more certain the closer it sticks to well established particulars. Narrative is never separable from explanation. Here Meyer anticipates the view later made explicit by the south western school, that history is idiographic rather than nomothetic, a science of the particular rather than of universal laws. The article is rough and leaves questions open, but it had the merit of inaugurating the Neo Kantian discussion of history. Like much of his work, it was soon forgotten. When Windelband, Rickert and Lask wrote in the eighteen nineties, they did not mention the colleague who had gone before them. Friedrich Albert Lange now enters the story. If he comes last among the five who revived Neo Kantianism, he does not come least. His History of Materialism of eighteen sixty six did more than any other single work to restore Kant to the centre of German philosophy. His influence eclipsed that of Fischer, of Zeller and even of Liebmann’s Kant and the Epigones. Yet his exact place in the movement has been disputed. He surely belongs to the physiological and psychological line of interpretation, alongside Fries, Beneke and Helmholtz. He regarded that line as the only way to secure Kant’s significance in a scientific age. Still, this is not the whole of his contribution. He transformed the Kantian split between noumenal and phenomenal into a split between ideal and real, norm and fact, value and existence, a shift from entities to logical types. In Lange one can already see the foundations of the theory of value that would define the south western school. He is often named the father of the Marburg school. The reputation owes much to his chair at Marburg and to his patronage of Hermann Cohen. Lange was professor there from eighteen seventy two to eighteen seventy five and helped bring Cohen onto the staff. Cohen expressed gratitude and stressed debts and affinities. Yet the likeness is superficial. On close view Lange and Cohen diverge deeply in their understanding of Kant and in their sense of method. Lange’s nominalism and empiricism, his psychological reading, his reduction of religion to aesthetic ideas and his critique of Platonism all offended Cohen. In truth, Cohen’s early philosophy grew in reaction against Lange. If Lange is a father, Marburg’s lineage was founded in revolt. He is also called the founder of Neo Kantian socialism. The label remains dubious. The case joins two facts that tempt connection, that Lange was a Neo Kantian and that he helped found social democracy. A third fact resists the join. Lange himself never grounded his socialism in Kant, nor did he seek a Kantian basis for social democratic ideals. In his two main works on politics he argues in utilitarian and perfectionist terms, and he rejects Kant’s moral philosophy as a guide to political economy. In The Labour Question he criticises Kant for deducing private property a priori and for excluding communal ownership of land. He thinks the institution arose from conquest, force and exploitation, and he calls Kant’s approach a servility to power and an apology for injustice. In Mill’s doctrines he prefers the principle of sympathy to the categorical imperative. Given his empiricism and naturalism the preference is unsurprising, though it is often overlooked by commentators eager to keep Neo Kantianism and socialism together. Because the link is weak and because the History of Materialism matters most for the movement, it is best to focus on the book rather than on his politics. Lange’s early life helps to explain the mix. Born in Wald near Solingen in eighteen twenty eight, with working class roots through a wagon driver grandfather, he absorbed the outlook that later shaped his politics. His father, Johann Peter Lange, rose to be a pastor and then professor of theology, and the family moved to Zürich when the father was appointed to replace David Friedrich Strauss. At the Zürich gymnasium a talk on Hegel’s Phenomenology awakened an interest in philosophy. He prided himself on being one of the few who understood it. He matriculated at Zürich in eighteen forty seven to study theology and philology, and attended the lectures of Eduard Böckh, a Herbartian, from whom he took a lasting interest in Herbart’s psychology. He began as a Herbartian and only later turned to Kant, disappointed with Herbart. From eighteen forty eight to eighteen fifty one he studied at Bonn, took philology and art history with Ritschl and Welcker, and absorbed a historicist method. He was largely self taught in mathematics, physics and the classics, learned English from fellow students, and so gained access to English thought that later shaped his moral and social views. He did little formal philosophy at Bonn, since philology was the necessary means to a school post. Brandis’s lectures on classical philosophy made an impression, and Lange told him that he had his own wild philosophy that he wished to grow before he subjected it to strict method. A letter of eighteen fifty one to a school friend reveals that early outlook. He leans toward a thorough relativism. There is no absolute content to conscience and no objective reality outside the mind for goodness, beauty or the God of theism. All that we know is relative to human beings and arises from their psychology and physiology. Only the laws of nature are objective, and they explain how the ideas of goodness, beauty and God arise of necessity from our nature. The belief in natural necessity makes him doubt the reality of freedom, which he treats as an obsolete notion in light of science. We call an action free when decision follows our own nature. Historicism, relativism and naturalism are all present in embryo. He finished with high honours, took a doctorate on Latin metre, passed the state examinations to teach languages, history, mathematics and psychology, and after a short military service taught at a gymnasium in Cologne. Frustrated as an assistant, he left for an academic career, habilitated in Bonn in eighteen fifty five with a dissertation on Herbart’s psychology and lectured on psychology, moral statistics, logic and pedagogy. During these years he began serious philosophical study and turned to Kant. He planned a critique of psychology on the model of the Critique of Pure Reason and the Prolegomena. A letter of September eighteen fifty eight states his motives and his stance. He rejects speculation, calls the Hegelian system a relapse into scholasticism, and regards Herbart as a bridge to Kant. He aims to complete what Kant did only halfway, the destruction of metaphysics. Every metaphysics is, to him, a delusion that can be justified only aesthetically or subjectively. Logic is probability calculus. Ethics is moral statistics. Psychology rests on physiology. He wants to move within the exact sciences. This positivist temper explains his sympathy with materialism. Yet it does not exhaust him. There is also the poet. He wrote verse on every occasion and would have made a life of it if poetry paid. That poetic gift lies behind the other side of his philosophy, what he later calls the standpoint of the ideal. Humanity has two sides, the rational spirit of the exact sciences and the poetic spirit that speaks through religion and art. His mature position will try to do justice to both. Other passages in the same letter sketch his view of Kant. He finds Kant’s greatness in theoretical philosophy and in the critique of metaphysics and embraces the lesson that philosophy must remain within the bounds of possible experience, which brings it into line with the exact sciences. On the practical side he praises Kant for showing that God, freedom and immortality cannot be proved, but he has little sympathy for Kant’s positive constructions, the attempts to secure belief in Providence and immortality. That seems a timid bow to orthodoxy. He also doubts Kant’s ethical method. Yet he accepts one essential feature of Kant’s practical philosophy, its starting point. He approves the attempt to justify moral and religious ideas by appeal to practical reason, even as he rejects Kant’s particular demonstrations of the traditional beliefs. Lange’s use of practical reason to defend morality and religion was already clear in his early correspondence, and it would later become central to his mature philosophy. For him, practical reason was not a faint remnant of metaphysics but the foundation for what he called the standpoint of the ideal, the space where ethical and aesthetic values could survive the collapse of speculative theology and dogmatic metaphysics. In 1855, during his first semester teaching at Bonn, Lange drafted lecture notes on logic that he later revised and delivered at Marburg in 1873–74. These lectures were published posthumously in 1877 by Hermann Cohen under the title Logische Studien. Though little read today, they reveal much about Lange’s early views on Kant and on the foundations of logic. His main concern was whether a formal logic—one that could claim apodictic certainty like mathematics—was possible without falling into the murky questions of epistemology or ontology. The formal logic he envisioned was not the later mathematical logic of Frege and his successors. Instead, he meant something closer to Aristotle’s syllogistic logic, stripped of its ties to grammar and metaphysics. The question was pressing in the 1850s because the Trendelenburg school had insisted that Aristotle’s logic could not be separated from his metaphysics and linguistic theory. Against them, Lange argued that the validity of Aristotle’s syllogisms did not depend on his views about being or language. No matter how one theorised about the structure of thought, the formal validity of syllogistic reasoning remained evident. That validity, Lange claimed, rested on its Anschaulichkeit—its intuitive graspability. We perceive the truth of the syllogism directly, as a relation that stands firm regardless of metaphysical assumptions. This immediacy, he suggested, stems from an a priori spatial intuition. The premise behind this peculiar thesis is that when we reason syllogistically, we imagine inclusion and subsumption in spatial terms: parts within wholes, regions within larger regions. Logical inclusion becomes a spatial operation of nesting. Lange then extended this claim into a broader theory of the mind. Spatial intuition, he held, underlies all part–whole relationships, all quantitative relations, even the very concept of number. Time itself, he said, is conceived through spatial imagination, as a point moving along a line. This view clearly draws on Kant, to whom Lange constantly refers in these lectures. Yet it also departs from him in two crucial respects. First, Lange rejects Kant’s distinction between analytic and synthetic a priori propositions. For Lange, all necessary truths are synthetic: their force comes not from contradiction or definition but from intuition. There is no fundamental difference between logical and mathematical necessity. Both depend on intuition, where a particular figure or sign represents something universal. Second, Lange disputes Kant’s separation of sensibility and understanding. All intuition, he insists, involves thought, and all thought involves intuition. Even logic depends on intuition. Spatial imagination is not confined to geometry but operates in reasoning itself. Logical structure and intuitive construction are inseparable. Alongside these early reflections, Lange began work on the project that would make his name: Geschichte des Materialismus. Its origins go back to his Bonn years. In 1857, his students asked him to lecture on the history of materialism, and he complied. Those lectures provided the first drafts for what would become one of the most influential philosophical works of the late nineteenth century. The first edition appeared in 1866, to great acclaim. A second, massively revised edition followed between 1873 and 1875, in two volumes and nearly twice the length. Lange revised it while gravely ill with stomach cancer, and he lived only a year after its publication, dying in November 1875 at the age of forty-seven. The History of Materialism was far more than a chronicle of doctrines. Like Lotze’s Microcosmus or Trendelenburg’s Logische Untersuchungen, it was a total worldview. Lange chose materialism as his subject because it captured the central intellectual crisis of his century—the clash between science and faith, between mechanism and meaning. The book’s argument is both historical and philosophical: it narrates the rise of materialism from Democritus to the nineteenth century and uses that history to clarify the philosophical limits of the materialist outlook. Lange’s key message was that materialism is a valuable scientific method but an untenable metaphysics. As a research programme, it promotes precision, scepticism and clarity; as a worldview, it overreaches. The message appealed to both scientists and theologians, to both liberals and conservatives, and the book went through ten editions, remaining in print well into the twentieth century. In the preface to the first edition, Lange explained that he wrote in response to the Materialismusstreit, the fierce public controversy over the implications of the natural sciences for religion and morality. He proposed to find a middle path between crude naturalism and metaphysical idealism, and he found that path in Kant. In his view, Kant’s philosophy alone could reconcile the scientific demand for natural explanation with the moral and religious need for meaning and value. For Lange, Kant’s enduring significance lay not in dogmatic moral theology but in critical restraint. The great insight of the Critique of Pure Reason was that reason must set limits to itself. Within those limits, the natural sciences can develop freely; beyond them, the sphere of ideals remains open as a domain of value, imagination and moral striving. This was the core of Lange’s standpoint of the ideal: to defend the autonomy of value without metaphysics and the autonomy of science without nihilism. To younger thinkers such as Friedrich Paulsen, Hans Vaihinger, and Hermann Cohen, this reconciliation between science and value was revelatory. They saw in Lange a philosopher who preserved the Enlightenment faith in knowledge and progress while safeguarding the moral depth of German idealism. Lange thus became to the 1860s what Reinhold had been to the 1790s: the populariser who made Kant once again a public philosopher. Yet Lange’s project was not purely academic. He repeatedly said that his aims were practical and civic. He wanted philosophy to help preserve the moral and cultural life of his nation amid the upheavals of industrial modernity. The History of Materialism was his attempt to hold together what modernity threatened to pull apart: science and spirit, fact and value, matter and meaning. For all its success, the book’s argument was subtle. Lange did not attack materialism from the pulpit of metaphysics. He shared its empirical, nominalist, and mechanistic commitments. What he opposed was its dogmatism, its uncritical realism, and its contempt for the ideal. The materialists, he wrote, had been right to expose superstition but wrong to think that the destruction of faith meant the destruction of value. Their real enemy was not religion as such but the authority that used religion to enslave thought. For Lange, the antidote to superstition was not cynicism but criticism. Science should liberate, not impoverish. The proper task of philosophy was therefore critical mediation: to distinguish the legitimate sphere of empirical knowledge from the creative sphere of moral and aesthetic ideals. Kant’s philosophy, rightly understood, was not a compromise between faith and reason but the foundation for a renewed humanism, one that could sustain the ideals of culture, freedom and beauty without recourse to dogma. From this point, his argument moves inexorably towards his critique of both speculative idealism and mechanistic materialism, preparing the ground for his own practical and aesthetic synthesis, the standpoint of the ideal, which he saw as the spiritual education modernity most urgently required. Lange cannot quite do without the thing in itself. In the first edition he defends its existence. In the second he tries to remove it as unknowable and faults Kant for asserting what exceeds his limits on knowledge. Yet he continues to rely on it as a limiting or problematic concept and even as an unknowable source or non ego that affects sensibility. The result is that the thing in itself proves functionally ineliminable. A pluralism of standpoints secures this result. The same object appears in irreducibly different ways to different kinds of being. A worm, a beetle, a human being and an angel each confront one tree yet form four representations. None grasps the tree as it is in itself. This variation underwrites Lange’s warning against projecting human cognition onto reality as such. He reads the transcendental project as a naturalistic research programme. The a priori is reinterpreted as stable features of our physical and psychological organisation that condition experience. Discovery may proceed empirically while the claim to apodictic demonstration is treated as a survival of rationalism. On this view the a priori ranges beyond space, time and the categories to include lawful structures in sensation and neurophysiology, for example regular relations between stimulus intensity and felt intensity. He often insists that the transcendental is not psychology in a doctrinal sense, yet he still grounds it in our constitution. He also distinguishes the empirical and the transcendental self, the latter an indeterminate X that conditions experience, which echoes the very difficulty posed by the thing in itself. He sets limits to monism. A full naturalistic explanation of consciousness remains impossible because neural processes and conscious qualities are heterogeneous. He moves between a two worlds manner of speaking and a Spinozist two aspects manner of speaking and then retreats, pointing again to the standing limit signalled by the thing in itself. At the same time he is a nomological exclusivist about explanation in the external world. Introspection may register what it finds, but genuine explanation is mechanistic and law governed, and natural laws suffice for human action in nature. The deeper dualism for him is not mental and physical but values and existence. Ideals do not disclose what is. They set norms for what ought to be. This anticipates the later value theory of the Southwest school. In that light he proposes to save religion by recasting it as aesthetic creation. Religion moves from dogma and metaphysics to poetry that embodies communal ideals. It belongs to the realm of value rather than knowledge and should be judged on aesthetic rather than theoretical grounds. He follows Romantic predecessors while denying cognitive status to the aesthetic. Traditional metaphysics becomes a positive philosophy that constructs world pictures artistically and is assessed by taste and historical spirit rather than universal validity. Critical philosophy collapses into empirical science. Philosophy as once understood is squeezed, a provocation to successors such as Cohen and Windelband. He justifies the practical force of Kantian ideas not by moral deduction but by an aesthetic necessity, with the sublime doing much of the work. He rejects universal a priori moral deductions and leans towards a historicist and sentimental grounding. Politically he and other Neo Kantians oppose Schopenhauerian and Hartmannian pessimism as quietist and potentially reactionary. Their alternative is neither optimism nor pessimism but a sober realism that affirms human autonomy and responsibility for change. Two lessons stand out. The attempt to eliminate the thing in itself fails because finitude and diversity of perspective force a reference to an extra subjective source. The bold naturalising of the a priori opens fruitful paths for inquiry but risks collapsing transcendental conditions into psychology. The appearance and thing in itself divide persists in practice, yet the master split becomes value and existence. With the aesthetic turn, religion and metaphysics are recast as poetic production, to be judged aesthetically rather than for truth. Philosophy is pressed from both sides by empirical science and by poetic system making, leaving little room for a normative and autonomous role, which explains the later reactions in Marburg and the Southwest. The political moral is a refusal of quietism that supports agency without faith in inevitable progress. Schopenhauer thought the best life was one of calm, detached contemplation. Live like that, he said, and you’ll be serene and at peace. That was his spin on the Stoic ideal of calm, the Christian idea of rebirth and grace, and the Buddhist goal of nirvana or enlightenment. Of these, he liked the Buddhist model best. According to the historian Kuno Fischer, Schopenhauer was serious about this, hoping Buddhism might become the West’s new religion. He cast himself as something like its sage and his book as its gospel. The Neo-Kantian reaction to Schopenhauer’s pessimism could not have been colder. They took apart every premise and conclusion and threw the whole package out. That might sound odd at first, since good Kantians don’t exactly cheer the pleasures of life; they will even concede that the world looks bleak by the standards of happiness. What bothered them wasn’t the grim portrait, it was what Schopenhauer did with it: the ethic of denouncing the will, renouncing life, and resigning yourself to the world’s ways. To the Neo-Kantians, that was surrender to evil. The point of life isn’t to flee the world, it’s to change it. With so much at stake, they felt they had to beat Schopenhauer’s pessimism decisively. And for about forty years, from the 1860s into the early 1900s, they kept coming back to that fight. One central strategy was to strip pessimism of any claim to be science or philosophy. In various ways, Windelband, Paulsen, Liebmann, Meyer, and Riehl all argued that Schopenhauer’s doctrine can’t be proven—neither empirically nor a priori. In the end, they said, it’s a statement of personal attitude, not a fact about the world. Whether life is worth living is a question of value, which is for each person to judge from experience. Who was Arthur Schopenhauer to tell everyone their lives are worthless? By pushing pessimism as if it were deep metaphysical truth, he blurred the line between facts and values. Values aren’t settled by pure reason alone; we can use many reasonable standards to judge life, and our conclusions will vary with the standards we choose. Windelband pushed this point hardest. The only way to make an objective claim about the value of existence, he said, would be if we knew the world’s purpose. Then we could ask whether the world fits that purpose. But we don’t and can’t know that, because metaphysics is impossible: as Kant rightly taught, we have no way to know reality as a whole. Another variation, developed by Paulsen and Meyer, was this: Schopenhauer’s pessimism would be scientific only if we had a “hedonic calculus,” some method to weigh pleasures and pains and see which side wins. He didn’t claim to have such a calculus, but his argument seems to presuppose it. He needs suffering to outweigh happiness overall to justify the verdict that life’s not worth living. But, they said, that presupposition is absurd. Pleasures and pains are too heterogeneous, and you’d have to measure not just amounts but kinds. Paulsen noted we couldn’t even do that for a single ordinary day. How would you weigh the pleasure of a good breakfast against the annoyance of burnt soup at dinner? Or the pleasure of reading a fine book against the irritation of background noise? If we can’t add up one day’s ledger, how could we do a whole life’s—let alone everyone’s? To be fair, Schopenhauer didn’t base his case on data; he thought it was a priori, built from general facts about desire, pleasure, and human life, more metaphysical than empirical. The Neo-Kantians knew this, and they met him on that ground too. Paulsen, Meyer, and Volkelt argued that Schopenhauer’s picture of pleasure and desire is flawed. He treats pleasure as something outside the act, a payoff at the end. But much pleasure is in the doing itself. There’s a difference between the pleasure of gratification (the feeling of fullness after a meal, the rest after effort) and the pleasure of activity (playing the piano, reading a good book). Schopenhauer narrows pleasure to gratification, as if that were the only kind, and then claims the pursuit of pleasure is painful. That move props up his pessimism, but it’s a mistake. They also objected to his claim that pleasure is merely negative—just the removal of pain. Even if desire aims to remove a lack, it doesn’t follow that satisfaction is only the lack’s disappearance. There can be a positive feel to satisfaction. And we have pleasures that aren’t preceded by felt deprivation at all—life has pleasant surprises. The most serious a priori worry targeted Schopenhauer’s core concept: the “will.” The Neo-Kantians doubted that he’d given it any clear meaning. Oto (Otto) Liebmann asked: what kind of will has no motive or end? To will is to will something; a will needs an object. Liebmann found it strange that the will was supposed to generate the body, when all the desires we know presuppose having a body. For his part, Meyer didn’t see how the essence of a person could simply be will. We are always conscious of ourselves as acting, yes, but acting can be thinking or feeling as much as willing. Later, Alois Riehl sharpened the point: “the will” is an abstraction from particular acts of willing, and every such act depends on a motive or purpose. Strip away motives, and you’re no longer talking about will but about bare desire. Will as a distinctively human kind of agency is purposive by nature. Schopenhauer’s metaphysical leap was shakier still. He held that will is the inner nature of everything, not just humans. He suggested that if I know the will is my inner nature, I’ll naturally generalize that to all things. To Liebmann, Meyer, Haim, and Riehl, this was a breathtaking leap across a chasm—treating the strict limits on speculation with astonishing nonchalance. Meyer thought the inference was bolder than anything by the “nature-philosophers.” And Riehl said the will, in Schopenhauer’s sense, was so mysterious that using it to explain the world was a case of explaining the obscure by the even more obscure. Critics also pressed a contradiction in Schopenhauer’s “redemption” story. He says the will directs the intellect, which is just a tool for means–ends calculation. If so, how can knowledge free us from the will and let us rise above striving? The intellect is supposedly bound to the will, yet somehow liberates us from it. Schopenhauer saw the problem and, at the end of The World as Will and Representation, tried to answer it—but mainly by restating his conviction that knowledge can change the will’s direction. That’s precisely what’s in question. In the end, he seemed to lean on reports of Christian and Buddhist spiritual lives. It apparently didn’t occur to him—though it later did to Nietzsche—that this “aesthetic” or ascetic life might itself be another form of the will’s drive, the will to power, just under the surface. Given that, the Neo-Kantians doubted that any real deliverance from suffering was possible on Schopenhauer’s own terms. What I’ve just sketched is only a slice of the Neo-Kantian polemic against pessimism. It was richer and more nuanced than this survey can show. But we should keep its secondary status in view. The point of the polemic was tactical: to undercut Schopenhauer’s quietism, his way of draining the will to change the world. Why the Neo-Kantians were so set against quietism, and how their philosophy is profoundly activist, is the next issue. Only when we see the roots of that activism can we fully grasp their stance on pessimism. 

Neo-Kantianism as a kind of new paganism (activist humanism) People often think pessimism is a nineteenth-century thing, especially from the 1860s on, when Schopenhauer was rediscovered and Eduard von Hartmann published The Philosophy of the Unconscious (1869). But pessimism is an eighteenth-century problem too. Its strongest early voice was Jean-Jacques Rousseau, who in his First Discourse (1750) argued that the progress of arts and sciences corrupts morals instead of improving them. That was a direct challenge to the Enlightenment, whose creed was that civilisation’s growth makes us better and happier. Kant, a committed Enlightenment thinker, was shocked by Rousseau’s thesis and felt obliged to respond. In a way, his mature philosophy is shaped by that response. If Kant is going to defend Enlightenment and the authority of reason, he has to answer Rousseau’s pessimism. Kant’s answer shows up in his 1784 essay “Idea for a Universal History with a Cosmopolitan Aim.” He never names Rousseau there, but the target is clear. Kant argues that nature’s own mechanism pushes us toward freedom and equality, toward a republican constitution, which is a better condition for humanity than the state of nature, where our powers would never develop. The core of the story is his teleology: nature aims at the full development of human capacities. Its mechanism is what he calls our “unsocial sociability”—competition for power, property, and prestige. That rivalry forces us to work, think, and invent, developing our abilities. Without this mechanism, humanity would live a pastoral dream of harmony and self-sufficiency—Rousseau’s idyll—but we would be sheepish in the bad sense, our powers undeveloped. We lose pastoral happiness, Kant admits, but we gain the flowering of human capacities. He then twists the knife: the same mechanism inclines us to build a republic. Self-interest pushes everyone to favour a constitutional order that maximises freedom while protecting each from others’ interference. A republic is a managed form of unsocial sociability, and that’s what most develops human powers. So the freedom and equality Rousseau mourned in the past, Kant relocates as a political goal for the future. There’s an implicit concession here: we may be less happy as culture advances. Kant isn’t bothered. He thinks happiness is the wrong measure. If nature gave us reason for the sake of happiness, it chose the wrong tool; instinct would have worked better. A pessimism that only weighs happiness misses the whole point of reason, which is to act for the sake of law, that is, for moral principle. The value of life isn’t to be found in pleasure but in being worthy of happiness—living for moral ideals. Chief among our shared ideals is the “highest good,” a state in which happiness is proportioned to moral desert. That fits with the republican ideal: a just constitution tries to match reward to merit. So the proper response to cultural pessimism isn’t to retreat but to take up political action toward a just order. Still, Kant puts real constraints on action. He doesn’t think human beings, acting together, can guarantee republican outcomes. Success depends too much on fortune. The emergence of a republic is due to nature’s mechanism—ultimately, Providence. So Kant’s reply to pessimism rests, in the end, on a kind of practical faith: that a divine design guides us toward our end. The Neo-Kantians kept Kant’s hope in progress but dropped his theology. They believed in human will and direct action, not Providence. People must take their fate into their own hands; they can’t wait for nature to do the work. If we organise politically, we can reform the order and move toward Kant’s ideals. You see this activist turn in Fichte’s Fifth Lecture “On the Vocation of the Scholar” (1794), given in Jena. Against Rousseau, Fichte says moral corruption is the fault of a specific culture and state—this regime—not of culture and the state as such. The golden age Rousseau longs for belongs ahead of us as a goal, not behind us as a memory. Fichte’s remedy is political activism. He ends with a call to action: act, act—that’s why we are here. No one believed more fiercely than Fichte in the power of the human will to transform the world. That Promethean faith, not Kant’s Providence, became central for the Neo-Kantian mainstream. The activist streak shows up clearly in the early 1860s. Figures like Kuno Fischer, Jürgen Bona Meyer, Rudolf Haym, and Eduard Zeller rallied around Fichte as a champion of liberal, national ideals after the failed 1848 revolutions. With a new Prussian king in 1861, liberals wanted to remind him of his duty to unify Germany. Who better than Fichte—the firebrand of 1794, who urged resistance to French occupation and demanded a single German nation? In May 1862, the centenary of Fichte’s birth was celebrated across Germany, with thousands attending in Berlin alone. Neo-Kantians spoke prominently. The “Fichte festival” helped rehabilitate Kant too, because many speakers underlined that Fichte’s philosophy grew out of Kant’s. Fischer led that line: he argued Kant’s system was “completed” by Fichte theoretically and practically. Just as Fichte eliminated the thing-in-itself from theory, he pushed the last religious remnants—Providence—out of practice. For Fischer, Kant reformed philosophy; Fichte wanted reform through philosophy. Armed with that optimism, the Neo-Kantians faced the new fashion for pessimism. For all the differences between Rousseau and the nineteenth-century German pessimists, they shared one dangerous idea: political action is futile. We cannot remove the sources of misery by striving. That quietism is what the Neo-Kantians could not accept. Quietism says you must resign yourself to life’s evils because they cannot be fixed. The Neo-Kantian answer: no—fight them. Schopenhauer’s World as Will and Representation might as well hang over its door the sign “abandon hope, all who enter.” In book four, he piles up reasons why resignation—the denial of the will to life—is the only sane response. Why is hope pointless? First, even if we create the perfect state, life’s intrinsic evils remain. The state’s job is to stop people harming one another; it can’t make us happy. And even if conflicts within states are settled, states will still conflict. Second, virtue can’t be taught; it rests on inner disposition and inborn character, so laws and schooling can only touch outward behaviour. That means political reform and education can’t make people truly virtuous. Third, there is no historical progress; everything stays the same—“the same, only differently,” as one of his mottos has it. The idea that history realises rational ends confuses contingent facts with necessary truths. Fourth, cosmic justice isn’t some ideal arrangement where happiness fits merit. The world itself is “just,” he says, only in the sense that whatever happens follows the will’s blind striving. Our job isn’t to judge the world by external moral standards, but to adjust ourselves to its immanent “justice,” resigning ourselves to whatever happens as a manifestation of the cosmic will. This is essentially a revival of old Christian and Buddhist ethics—salvation through self-denial and renunciation. Schopenhauer knew it and leaned into it. He said the heart of Christianity lies in recognising the nothingness of earthly happiness and turning toward a wholly different life. Near the end of The World as Will and Representation he emphasises the affinity of his ethics with Christian self-abnegation. He didn’t believe in God or heaven, but he rehabilitated ideas of sin, grace, deliverance, and redemption—now defined as withdrawal from the world and renouncing all striving. Nothing could be further from Fichte’s Prometheanism. Instead of resignation, Fichte preaches rebellion and transformation. The very will Schopenhauer wants to extinguish is what Fichte wants to ignite. For Fichte, striving is the only means to redemption, because only striving can realise the ideals of a republic. Nowhere is Fichte farther from Christian tradition than when he says that the union of all striving, Fichtean agents would be nothing less than “God.” It’s an unreachable ideal, but we can approach it. That Promethean spirit is the driving force behind the Neo-Kantian critique of pessimism. It’s not always explicit, but it’s there—sometimes very clearly. Take Herbart’s appreciative yet critical review of The World as Will and Representation (1820). Schopenhauer had claimed that optimism is both absurd and harmful because it makes light of human suffering. Herbart’s reply: he is an optimist of a practical kind. The world is a rough place, but he is disposed to do what he can to improve it. Physical suffering is bearable, he says; the deep sources of misery lie in social relations, which we are duty-bound to reform. He compares humanity to a neglected bean patch: plants grow wildly; some smother others from lack of light. If beans were conscious, they’d become Schopenhauerian pessimists, lamenting the useless urge to live and then renouncing it. But the problem isn’t hopeless. They lack gardeners with poles and twine to train growth so all can thrive. The moral is obvious: humanity needs reformers who can guide social life by wise laws and institutions. Herbart’s faith in education and reform shows how much Fichte remained in his bones. Or consider Meyer’s illuminating essay “Pleasure and Pain” (1886). He imagines what most of us would do if offered the chance to end life’s burdens at once. Some might take it, as Schopenhauer predicts. But many would act like the overburdened man in the fable who, when Death approaches, quickly hoists his load again and asks only for help to lighten it. The lesson: life is not intrinsically unbearable; with mutual help, it’s endurable. Writing in the late 1880s, Meyer finds the ongoing vogue for pessimism puzzling. Look at the age’s achievements—national unity, victory in war, technical and social progress. These are not times for black lamentation. We can renew our faith in a moral world order—but not by invoking Providence or the “laws of history.” Our faith rests on our own actions. We should build that order through our deeds. Humans aren’t born to suffer, lament, or resign themselves. Life’s purpose is to fight evil and misery. Our deepest happiness lies in working for the good, the beautiful, and the true—and that striving is itself a source of joy. Otto Liebmann made the point vividly in a charming “Trilogy on Pessimism” from his book Against the Skeptics. He tells three stories: Hegesias, the ancient who taught suicide as the only way out; Timon the misanthrope, who retreats from humanity after being cheated; and the Buddha, who teaches renunciation of desire. Liebmann finds each attitude understandable but ultimately too extreme. Life is neither heaven nor hell, and we aren’t gods, looking down at it as if it were merely a play. We should struggle and act. In itself, existence is neither good nor evil; those are relative to how we take things and what we do with them. By now the pattern should be clear. The clash between Neo-Kantianism and pessimism is, at bottom, the clash between Fichtean activism and Schopenhauerian quietism. That wasn’t their only point of friction, but it was the live wire. 

University philosophy and Schopenhauer’s broadside In the late 1840s, Schopenhauer wrote an essay, “On University Philosophy,” for his collection Parerga and Paralipomena, attacking the whole practice of teaching philosophy in universities. Professors, he said, are servants of church and state, modern sophists who live off philosophy rather than for it. His main targets were Fichte, Schelling, and Hegel, but he also took shots at early Neo-Kantians like Fries and Herbart. He died before the Neo-Kantian “movement” took shape in the 1860s, but it’s clear what he’d have said about its members: most were professors and would have been in his crosshairs. Because the essay is biting and witty, it was widely read, and Neo-Kantianism has lived in its shadow ever since. The piece helped cement the picture of Neo-Kantianism as conservative, backing the status quo. It also fed the idea—later reinforced by Kierkegaard and the young Nietzsche—that the truly creative nineteenth-century philosophy happened outside the university: Schopenhauer, Marx, Kierkegaard, Nietzsche—these are the revolutionary figures, so the story goes, and they get the textbook chapters. The Neo-Kantians, being professors, drop out of sight. It’s worth taking Schopenhauer’s complaint seriously but also checking it against the record. The essay is mostly a screed—mocking, sweeping, short on careful argument. We learn little about what’s actually wrong in Fichte, Schelling, or Hegel. His motives aren’t hard to guess: he felt ignored by the professoriate and imagined a conspiracy to deny him recognition. Had those professors praised him, would he have written so fiercely? Hard to believe. Still, the essay isn’t worthless. Schopenhauer points to a real danger: state universities can constrain intellectual freedom. Professors are employees; the state can censor. Philosophy, however, needs freedom to follow the truth wherever it leads, regardless of consequences for church or state. Lessing made that case in the eighteenth century; Schopenhauer extended it to the university setting. That’s a serious concern even today—especially in systems where professors are civil servants. But does his portrait fit the Neo-Kantians? Not really. From the 1820s to the 1860s—the formative decades—many early Neo-Kantians were harassed or prosecuted by the state. They paid for their convictions. Fries, Beneke, Fischer, Zeller, and Lange all suffered in one way or another. As for their reaction to Schopenhauer’s rant, they knew his views before the essay was published; he had scattered jibes at Fichte, Schelling, and Hegel through The World as Will and Representation. They thought his tone beyond the pale. Beneke called the tirades unworthy of a philosopher; Herbart went out of his way to note how close some of Schopenhauer’s ideas were to Fichte’s later thought—proof that the lines weren’t as stark as the polemics suggested. Later Neo-Kantians answered him more directly. In one of the first monographs on Schopenhauer, Rudolf Haym mocked the university essay as a torrent of invective—“noisy insults.” He repeated the point about Schopenhauer’s rudeness: never had public debate seen such unvarnished coarseness. The roughness wasn’t about ideas; it was about personality—vanity and the hunger for fame. Haym also noted Schopenhauer’s debt to Fichte, which Schopenhauer tried to obscure. Kuno Fischer, for his part, argued that nothing would have helped Schopenhauer more than sustained university work: teaching would have forced him to clarify and update his ideas, face objections, and engage the sciences, instead of repeating early convictions in isolation. Paulsen took a more psychological tack in an 1882 essay later republished in his book on pessimism. He said you can’t make sense of Schopenhauer’s contempt for professors unless you see the obsession with recognition beneath it. What did he want from professors? Not reviews or citations, but disciples. Ironically, the very independence Schopenhauer doubted in academics is what kept them from becoming his acolytes. Paulsen also thought Schopenhauer knew himself too well to stay in a job that demanded exams, grading, and committees—he wasn’t cut out for that life. Behind the contempt, Paulsen saw class snobbery: a patrician disdain for those who had to earn their living by lecturing and publishing. Fischer went further and compared Schopenhauer’s life to his preaching. Here was a man who praised renunciation but lived like a bon vivant, who preached humility but craved literary glory. Judge him by aesthetic, not ethical, standards, Fischer suggested, and it makes sense: he saw himself, like many Romantics, as a genius, and he kept the pose. In a larger study of Schopenhauer’s life, Fischer highlighted two telling discrepancies. First, Schopenhauer’s desire for an academic career: he was a university man himself and attempted to secure posts. He lectured one semester in Berlin and kept his status as a private lecturer for ten years—using it to impress a British publisher—yet later railed against “university philosophy.” Sour grapes may have done some of the talking. Second, Schopenhauer styled himself a nineteenth-century Lessing, champion of free inquiry; but when political reaction came in the 1850s, he rejoiced as left-wing professors lost their right to teach. The supposed hero of academic freedom cheered on censorship. Fischer had reason to push back. Schopenhauer had smeared the integrity of people who had paid a price for their views: Ludwig Feuerbach, David Friedrich Strauss, Theodor Vischer, Bruno Bauer, Arnold Ruge—many were persecuted and lost university hopes on principle. Fischer could have added Zeller, Lange, and himself. Leave aside the personalities, though. There is a philosophical kernel in Schopenhauer’s complaint. He charges that professors—under the thumb of theology—ignore the most basic question: whether life is worth living. Later, Karl Löwith would say something similar about Neo-Kantians: they lost sight of this existential question, which became central for Kierkegaard, Nietzsche, and the neo-Hegelians. There’s some truth there. In the 1860s and early 1870s, Neo-Kantians often defined philosophy as “the logic of the sciences,” leaving out its traditional ethical concerns. But they recognised the shortcoming and broadened their definition in the 1880s and 1890s, making room for ethics and the question of life’s value. On that question, they parted ways with Schopenhauer, Kierkegaard, and Nietzsche in one crucial respect: for them, the value of existence is largely a political question. The state can’t cure all suffering, but a just state—founded on liberty, equality, and fraternity—makes life far more bearable and worthwhile. Schopenhauer, Kierkegaard, and Nietzsche, in their view, made suffering eternal by ignoring the role of society, the state, and history. The neo-Hegelians would make similar complaints, though the Neo-Kantians rejected Hegel’s faith in historical inevitability. For them, the world becomes more rational only by our actions—by taking responsibility and building better laws and institutions. 

The rise of Darwinism in Germany (brief setup) By the end of the nineteenth century, one historian quipped that Germany had produced Darwinism as France had produced Newtonianism. Darwin himself looked to Germany for support, telling the biologist Wilhelm Preyer in 1862 that German backing gave him hope his ideas would prevail. He got more than he hoped for. Around 1899, a Berlin magazine’s reader poll named the three greatest thinkers of the century as Helmuth von Moltke, Immanuel Kant, and Charles Darwin, and picked On the Origin of Species as the most influential book. Why did Darwin take such deep root in Germany? There’s no single reason. Politically, after the failure of the 1848 revolutions, left-leaning intellectuals shifted the fight from barricades to ideas, building a secular, humanist, materialist worldview to counter the throne-and-altar alliance. Darwin seemed to remove the need for supernatural intervention, so he became a useful ally. Early German Darwinians even linked his theory to social progress: what Darwin saw in nature—the improvement of species through struggle—many translated into politics as the natural law of advancement. Ernst Haeckel’s famous 1863 lecture “On the Modern Development of Darwinism,” delivered at a meeting of naturalists and physicians, makes this crystal clear. He argued that the same principles—struggle for existence and natural selection—drive civil and social life toward higher culture. Reactionary efforts by priests and despots might slow progress, he said, but because progress is a natural law, they will only provoke stronger advances. Intellectually, Darwin’s seed fell on prepared soil. In the 1840s, German “biophysics” promoted mechanical explanations of life; in the 1850s, a robust materialism was popularised by figures like Vogt, Büchner, and Moleschott. When Darwin appeared, many were ready to welcome him. Even though Darwin avoided crude materialism, German materialists eagerly claimed him, and the public soon linked Darwinism with materialism. There was little scandal in Germany as there had been in England; the ground had already been cleared. Within weeks of Origin’s 1859 publication in Britain, Heinrich Georg Bronn offered a German translation, which appeared in 1860 and again in 1862. Reception was cautious at first—Huxley joked that “Germany needs time to consider”—but Haeckel’s 1863 lecture electrified audiences and pulled many along. Newspapers noted the excitement and applause. Haeckel was only the first of a spirited cadre—Alfred Brehm, Carl Vogt, Ernst H. Müller, Fritz Müller, Wilhelm Preyer, Friedrich Ratzel, Ludwig Büchner—who championed Darwin. By the late 1860s, Darwin dominated life-science debates. As Friedrich Albert Lange observed in the second edition of his History of Materialism (1875), the controversy over materialism had already morphed into a controversy over Darwin. By the mid 1870s the old German materialists had faded into the background, as Lange noted. A new edition of Büchner’s “Force and Matter” no longer caused a stir, and Moleschott was almost forgotten. All eyes were on Darwin. You were either for him or against him. Estimates at the time already called Darwinism the winner in Germany. Darwinians were growing in number and clout. Haeckel and Carl Gegenbaur were now professors in Jena, and they steered important journals such as Das Ausland and Kosmos. The anti-Darwinian camp was shrinking and aging. Only a few held the line, among them Adolf Bastian, Albert Wigand, and Rudolf Virchow. In 1875 Otto Liebmann quipped that, apart from religious zealots and a few cranks like himself, almost all intelligent opinion in Germany now sided with Darwin. Darwin’s prestige had gone fully official. In 1867 he was made a knight of the Prussian Order Pour le Mérite, and in 1878 he was elected to the Berlin Academy of Sciences. It is striking that the rise of Darwinism coincided with the rise of Neo-Kantianism. Both crystallised in the 1860s and dominated the 1870s and 1880s. How they related depended on whether people tied Darwin to materialism. Some Neo-Kantians insisted on a sharp line between Darwin’s theory of natural selection and materialism. Natural selection was an empirical theory, they said, while materialism was a sweeping worldview that overreached. If Darwinism meant only the selection theory, they were happy to endorse it. They welcomed its naturalism and mechanism as genuine scientific progress. If Darwinism came packaged with materialism, especially in Haeckel’s version, they fought it hard. Haeckel was, to them, a materialist in disguise who needed to be exposed. There was no single party line among Neo-Kantians. Three figures from the 1860s generation led the early responses, and they disagreed. Friedrich Albert Lange was enthusiastic, Jürgen Bona Meyer was highly sceptical, and Otto Liebmann was cool and halfway. Lange and Meyer were glad to leave Aristotle behind. Liebmann wanted to keep parts of the Aristotelian legacy and fuse them with Darwin. Even with all these differences, each response was recognisably Kantian. Lange stood for Kant’s naturalism and mechanistic streak, Meyer for his scepticism about what we can know, Liebmann for his dualism about nature and freedom. Only at the century’s end did relations sour. Haeckel’s blockbuster “The Riddle of the Universe” in 1899 alarmed Neo-Kantians. Here was a bestselling, basically materialist book that claimed Darwin’s authority. Later Neo-Kantians such as Friedrich Paulsen and Erich Adickes wrote polemics against Haeckel. In them, another Kantian theme came to the fore, a firm antimaterialism. Darwin’s success forced a big question on Neo-Kantians. Can biology count as a science in the Kantian sense. Kant’s own negative verdict looked dated in light of Darwin. Kant had denied that origin stories about species could stay within the bounds of experience, and biology hardly matched his mathematical model of science. The challenge for Neo-Kantianism in the later nineteenth century was to rethink its picture of science so it could fit the day’s actual sciences. Otherwise Kant’s philosophy would seem tied to an older scientific era. This chapter looks at how they took up that challenge in biology. First, the 1870s responses of Lange, Meyer, and Liebmann. Then, the early 1900s critiques by Adickes and Paulsen against Haeckel. 

 Lange, the naturalist The first Neo-Kantian to engage Darwin in depth was Friedrich Albert Lange. He wrote about Darwin in the first edition of “The Workers’ Question” in 1865, and again in the first edition of his “History of Materialism” in 1866. In the second volume of the second edition of the “History,” published in 1875, he greatly expanded the Darwin material, turning a 12-page note into a 44-page chapter on Darwinism and teleology. Looking back, Lange said that when he first wrote on Darwin, the fight had not yet begun. Friends of Darwin had not organised, foes had not absorbed the message. By the second edition Darwin ruled the field, and biology revolved around him, so Lange felt he had to go much deeper. Of all Neo-Kantian treatments, Lange’s was most sympathetic. The materialist leanings that are usually implicit in his “History of Materialism” became explicit with Darwin. For Lange, Darwin was an ideal of the modern world, the foremost voice for scientific naturalism. Natural selection was the triumph of that naturalism. It showed that a naturalistic method could explain organic nature as well as inorganic. Where Liebmann later raised philosophical worries and Meyer raised empirical ones, Lange endorsed Darwin both philosophically and empirically. Philosophically, Darwin pushed a naturalistic worldview that spoke to both heart and intellect. Empirically, the theory gave a unified explanation that no facts had overturned. Lange admitted parts of the theory were still hypothetical, but he was confident research would confirm them. Darwin shaped Lange’s politics too. In “The Workers’ Question,” a classic of early German socialism, Lange puts the struggle for existence at the centre. He takes it straight from “On the Origin of Species,” which he cites at length five years before Darwin published “The Descent of Man.” The struggle applies to people as much as to plants and animals. In civil society the struggle plays out in the market. Workers compete to survive, just as organisms compete for scarce resources. Nature scatters enormous seed for a few plants to grow. Society throws up an enormous supply of workers and only a few get a living wage. Natural selection and the struggle for existence mean the strong rule the weak, not only in nature but also in society. An elite will dominate the many. Lange even speculated that, if class divisions persisted for millennia, they could harden into quasi racial differences between workers and bourgeois. Unlike Haeckel, Lange did not think these mechanisms yield steady progress and perfection. He thought the opposite. Left alone, they create oppression and misery. It is a grim picture, and he denies his reader even the thin consolation Darwin adds at the end of Origin’s third chapter. We know the terrors of annihilation, we feel the pressure of perpetual struggle, and virtue offers no guarantee of survival. So far Lange may sound like a social Darwinist. In fact he uses Darwin against social Darwinism. He wants to show the plight of workers and the need for reform, so that law and policy can cancel the blind effects of selection. For Lange, selection and struggle are not fate. People can and should resist them, and soften them, through institutions and politics. Two forces move history. Natural forces push toward inequality and domination. Moral and spiritual forces push toward equality and freedom. History is their ongoing conflict. That sounds like a reprise of Kant’s split between nature and freedom. Lange had questioned that split in the “History of Materialism,” placing moral action inside the phenomenal world. One might wonder how his politics escape the struggle for existence without bringing back some version of that dualism. Hoping to collaborate, Lange sent “The Workers’ Question” to Marx and Engels in March 1865. They pushed back, mainly against the Darwin theme. Engels replied at length that modern inequality springs from social and economic relations, not nature, above all from private ownership of the means of production and the class conflict that follows. Economic laws are not eternal natural laws. They are made by people in specific social conditions. Engels implied that Lange, like the classics of political economy, hypostatised contingent relations as natural law. Lange took note. In a later edition he replied that class conflict would not arise if workers were not forced to compete and sell themselves on the market to subsist. Competition and the need to live are basic natural facts behind social conflict. The factory owner’s power is one expression of his position in the struggle for existence. Darwin mattered for Lange’s whole outlook as well as for his politics. The modern ideal, for him, vindicated naturalism, mechanism, and nominalism against teleology and Platonic-Aristotelian realism. Because Darwin had excited so much opposition, Lange set out to defend him in the “History of Materialism.” Much of his Darwin chapter is a critique of what he calls the new Aristotelians. Resistance to Darwin, he says, comes from those who cling to an old teleological world picture. They argue that gaps in mechanical explanation must be filled by purpose. They picture creation by analogy with human craft. As we design a machine, so God designs an organism. Lange answers that natural selection has swept away this anthropocentric teleology. Leaving aside Darwin’s breeder analogies, Lange stresses one key implication. Nature does not make organisms the way we make artefacts. We choose simple, efficient means, and we try to leave nothing to chance. Nature showers the world with chances. It fires a blunderbuss of seeds. A few survive. Judged by human standards, nature looks like blind luck. Success is the exception in a sea of birth and death. Old teleology turns the exception into the rule, as if nature followed a plan. Much of Lange’s anti-teleology assumes that teleology means a supernatural interruption of mechanism. By mid century almost no serious philosopher held that view. Schelling and Hegel, then Trendelenburg and Lotze, had revived a different teleology, one in which purposes work through mechanisms, since mechanism is the means by which ends are realised. Lange notes this and even calls it the correct teleology, then limits it by recalling Kant’s “as if.” We may use purposiveness as a regulative idea in life science, but it has no metaphysical force. We cannot say nature really has purposes, only that we must often proceed as if it did. Kant, Lange says, gives two such ideas that fit naturalism. One is a formal purposiveness, where we organise inquiry as if nature formed a system of genera and species. The other is an objective unity, where we treat organisms as if designed. Neither commits us to real purposes. Kant’s teleology does not end mechanical explanation. It says only that the work of mechanical explanation is never finished. For Lange, the more science advances, the less we will need even the regulative language of purpose. He thinks Kant went too far in treating teleology as a necessary habit of the mind. Lange also tackles species. Fixed, eternal species had been a pillar of anti-Darwinian resistance, so he takes it on. Even some materialists, such as Carl Vogt, clung to fixity. Lange has no patience with that. He calls it the most conspicuous superstition in science. It persists, he says, because of ancient roots in Aristotle, who treated universals as if they existed in things. As a nominalist, Lange treats that as hypostasis. He does not lean on this point in the Darwin chapter. Instead he makes two pragmatic arguments to show the doctrine is obsolete and redundant. First, the doctrine came from doing biology without a microscope and starting at the top of the scale. Start with the microscope and the lower end, and you are overwhelmed by the profusion of forms that do not fit neat Linnaean boxes. Second, Darwin can explain the relative stability of species. Once a population fits an environment, it can persist for millennia, which gives the impression of fixity. We can explain that impression without invoking real universals or a creator. Lange tries to uproot another Aristotelian legacy, the idea of organic form. Even committed mechanists like Virchow and Vogt kept it to explain an organism’s essence. For Lange it is another scholastic relic. It relies on two assumptions. The whole is prior to the parts. Every part has a necessary role in the whole. He rejects both as obsolete. Modern research shows that parts can live and act apart from wholes, for example isolated cells, or a frog’s heart beating after dissection. Organs can be transplanted. At the lower end, creatures join by fusion of independent cells. As a mechanist he gives priority to parts, and treats the whole as the sum of parts. He wisely does not press this to an extreme. He concedes that the old assumption holds in many cases, and denies only that it is a necessary truth. He also questions the assumption of natural unities. A plant or animal looks like a self-sufficient unity. We are tempted to think something holds it together from within. That, Lange says, is a hangover from Aristotle. We think there is a real universal, a species essence, that makes the unity. For Lange, unity is due to how we group things in thought. Nothing stops us from treating the parts as unities too. The whole plant is one, so are the stem, the leaves, and the bud. Each can count as a living unit in its own right. Lange leans here on recent research, especially Haeckel’s work on radiolarians, tiny marine invertebrates that can live on their own or fuse into larger organisms. Whether we treat them as unit or part depends on the investigator’s perspective. On classification, Lange’s radical nominalism drifts away from Darwin. Darwin rejects both Aristotelian essentialism and pure convenience. He argues that the right basis of classification is genealogy, the lines of descent. Lange is less concerned with that point. He is not trying to be Darwin’s bulldog. His chapter both defends and revises Darwin. He worries that certain formulations make the theory vulnerable, so he advises amendments. Darwin’s main mistake, Lange thinks, is to lean too hard on natural selection, as if it were the only mechanism. Selection determines which forms survive. It does not determine which forms are possible. That is the pool of variation, and the source of variation needs its own account. Lange also presses the familiar worry that Darwin gives no clear source of variation. Darwin separates variation from environment, as if useful novelties were sheer chance. To ease this, Lange proposes a law of development for each organism, a built-in pattern that sets its structure and stages of growth. He borrows the idea from German anatomists such as Bronn, von Baer, and Kölliker. For Lange this means an organism has an inherent drive to survive and adapt. When conditions change, that drive produces variations that fit the new world. This reads Darwin in a Lamarckian way, with acquired traits inherited. Lange praises Darwin as if he had proved such inheritance. Does this smuggle in substantial forms. Lange says no. The law of development is not mystical or purposive. It is the unity of many mechanical laws working together, which creates the appearance of directed growth. To calm doubts, he floats Haeckel’s chemical suggestion. Since life is based on carbon, perhaps the plan of growth is nothing more than the characteristic substitutions and combinations of carbon. On one large claim Lange keeps his distance from extreme Darwinians. He is cautious about monophyletic descent, the idea that all organisms come from one primal ancestor, and about strict recapitulation theory. Similar early stages may be only superficially alike. We should not confuse morphological likeness with real identity. Microscopic structure and chemistry may differ under the surface. It is more plausible, he says, that basic types come from different original seeds. That fits the great variety of forms. There is much more in Lange’s chapter than we can summarise here. The sketch above gives the main lines.

Meyer, the sceptic The sharpest and best informed Neo-Kantian critic of Darwin was Jürgen Bona Meyer. Trained in medicine, he was at home in anatomy, zoology, and embryology, and well read in recent French and German biology. He also knew the history, having written his habilitation on Aristotle’s biology under Trendelenburg. None of Trendelenburg’s neo-Aristotelian animus against Darwin rubbed off. Meyer revered Aristotle as the father of organic science, but not as a model for future biology. As soon as Darwin’s work appeared, Meyer dug in. He read Origin closely, and “Variation of Animals and Plants under Domestication.” In 1866 he wrote a long review of the German translation of Origin’s second edition. A few years later, in “Philosophische Zeitfragen,” he gave a 65-page, exacting examination. He begins with respect. No one, he says, should doubt Darwin’s thoroughness and learning, or his contribution to science. Even if one disputes his conclusions, Darwin reopened questions that had been treated as settled. Above all, he forced a re-think of the fixity of species, which had been a near dogma in the early nineteenth century. Georges Cuvier, head of the Academy of Sciences, had reaffirmed fixity with data, method, and zeal in his “Animal Kingdom.” He insisted on exact observation, condemned nature-philosophy speculations, and piled up facts, so his stance looked like sober science. Lamarck and Geoffroy Saint-Hilaire looked like dreamers, lacking data. By mid-century, new fossils had shaken Cuvier’s authority, and Darwin’s timing was perfect. After Darwin, Meyer wrote, no one could doubt that species change. The live questions were how and how far. Meyer notes one of Darwin’s best moves. He questioned sterility as a strict mark of species. The old argument had been simple. Breeding across species leads to no offspring or to sterile offspring. That is nature’s boundary stone. Fertile crosses happen only within species. Darwin challenged this. Many distinct species can cross, many similar ones cannot. Fertility and sterility come in degrees, and there is no clear line. Since the terms species and variety are ill defined, these debates go in circles. Naturalists define species by successful interbreeding, then use successful interbreeding to prove species identity. Meyer thinks Darwin did not give enough evidence for fertile crosses of true species, yet he praises him for ditching fertility as a general criterion, and for putting the whole matter back into empirical hands. Meyer himself does not take a stand on whether one species evolves into another. True to his scepticism, he remains agnostic. The evidence was not enough either way. He insists that naturalists respect the limits of knowledge and hold back from speculation beyond experience. On this score, he says, both Darwin and his opponents overreached. Cuvier and even Alexander von Humboldt defended fixity on the slender basis that many species had not changed since ancient Egypt, which is far too short a time window. Darwin’s broader window shows only that species have changed, not that one species has grown out of another. Hypotheses are fine in science, Meyer says, provided we keep the difference between hypothesis and fact straight. Here he calls Darwin a sinner. Darwin blurs the line and presents speculation as if it were science. This was bound to be controversial, since Darwin prided himself on staying within experience and bringing slippery topics into scientific reach. Meyer grants that virtue to a point, then argues that Darwin violates his own method where it matters most. Meyer’s central technical complaint is variation. Darwin puts weight on inheritance and the reproductive system, and less on environment, because children of the same parents differ even in the same conditions. Yet Darwin hedges. He also says environment can affect the reproductive system. On facing pages he calls heredity the predominant power, then calls the conditions of life of the highest importance. Meyer pounces on the ambiguity and repeats the charge of obscurity. Darwin himself had admitted that the laws of heredity were unknown. Meyer praises the modesty, then faults him for building too much speculation on that admission. Like Lange, Meyer sees Darwin leaning toward Lamarck, more often than people admit. Darwin often appeals to use and habit. When Darwin tries to reconcile heredity and environment, Meyer says he lands very close to Lamarck. Environment acts indirectly, through effects on reproduction, which then produces variation. Lamarck could agree with that. The difference is emphasis. Darwin stresses reproduction. Lamarck stresses environment. Meyer pushes a revision. The struggle for existence should not be separate from variation. It should be one main source of variation. Darwin treats them as independent variables. If we separate them, then adaptation hangs on luck. Variation by pure heredity need not be adaptive. Often nature reproduces bad or indifferent variants for generations. Even if a useful trait appears, there is no guarantee it will carry on. Parents can die before breeding. They may not mate with similar carriers. Offspring may not inherit the trait. They may not survive. Given this long chain of contingencies, Meyer wonders how any useful trait becomes established without a large dose of luck. For Meyer the only way to reduce the role of chance is to take the selection metaphor literally. Darwin’s core analogy is artificial selection. Breeders change species by choosing. Nature does something similar, he says, and even more powerfully, because it works on the whole machinery of life. But the idea of a selector suggests an intelligence or a design that ensures useful variants are chosen. Darwin insists no such agent exists. Selection is just the name for the results of many small survivals in the struggle for life. Meyer replies that only a literal selector makes sense of the key fact Darwin wants to explain, the emergence of new species. Without it the chance element is too high. In short, Meyer thinks Darwin cannot so easily banish teleology from his theory. On Meyer’s final balance sheet, Darwin’s vice is grand speculation without evidence. He talks the talk of empirical science, but does not always walk it. The thinness is clearest when he argues that one species can become another. The hardest evidence he offers is pigeon breeding. Many varieties come from the rock pigeon. That shows that a pigeon remains a pigeon. It does not show transformation of species. There is even less evidence for universal descent from a few primitive ancestors. The fossil record shows that very different animals once existed, not that they grew out of one another, still less that we grew out of them. Embryology and morphology show affinities, but similarities in structure are not proof of genealogy. Meyer’s model for handling the origin of species is straight from Kant. He cites Kant’s 1775 essay on human races, which set strict limits on origins talk. The limits of natural explanation lie within possible experience. We exceed them when we speculate about the origin of life itself. Kant goes further and warns us off speculating about the origin of species. Experience shows only how one creature comes from a similar one. To argue about how one species arose from a different one is an adventure of reason. That is exactly what Darwin attempts. Meyer’s verdict is that Darwin’s hypotheses outrun science. Hypotheses can be useful when they explain facts. They lose value when there are no facts to explain. In Darwin’s case, Meyer says, we have presumed facts built for the sake of the hypothesis. Meyer denies he is holding Darwin to a higher bar than Darwin set for himself. He stresses that they share the same ideals of observation and experiment, and he concedes that Darwin sometimes meets his own standard. Kant’s limits on experience did help on some fronts. Darwin had been careful when testing fertility as a mark of species, in showing that variability runs wider than people assumed, and in consulting the geological record to back change over time. Still, he went beyond experience when he treated species as transformable and as descending from a few parent stocks. Meyer’s critique, though sharp, raised problems of its own. It is one thing to say Darwin outran the current evidence. It is another to fault him for asking questions that could never have evidence. We have to distinguish scientific speculation from metaphysics. Meyer did not keep that line clear. That left room for a fair reply in Darwin’s favour. Darwin’s guesses were scientific, even if underpowered by data. In principle they could be tested. Further observation and experiment might confirm them. Darwin knew he was pushing the envelope on origins. He also thought new evidence would come, which by Meyer’s own lights had already begun to happen. Meanwhile, could such bold hypotheses not serve a purpose, by steering inquiry. Drawing boundaries for knowledge is tricky. Draw them too tight and you choke inquiry, which is dogmatism. Draw them too loose and you let in metaphysics, fantasy and fervour. Meyer drew them too tight. By insisting that speculation must rest only on already verified facts, he shrank theory to what was already known. He judged like a philosophical sceptic, not like a working naturalist. Had Darwin followed Meyer’s rules, there would be no Origin of Species. That is the final undoing of Meyer’s scepticism. The last Neo-Kantian to take Darwin on at length was Otto Liebmann. He wrote a long essay, “Platonism and Darwinism,” in his book “On the Analysis of Reality” in 1876, then several shorter pieces in “Kant and the Facts” in 1899. Liebmann carved his own niche. Unlike Lange and Meyer, he brought back the old Aristotelian line that Darwin had set out to overturn. He was not trying to roll back the clock. His aim was to reconcile the warring camps, so the English naturalist and the Greek could live in peace. His reconciliation was Neo-Kantian in its own way, founded on Kant’s dualism between the natural and the normative, the phenomenal and the noumenal. When Liebmann first wrote on Darwin in the early 1870s, he felt he was swimming against the current. Darwin’s theory was so entrenched in Germany that life science revolved around it. The public, unless held back by religious scruples, had largely converted. Liebmann counted himself among the rare few who wanted to question it. He did not attack Darwin empirically. He wanted to mark its philosophical limits. His key question was whether Darwin’s theory could underwrite a materialist worldview. Were Büchner, Vogt, and Haeckel right to treat Darwin as their gospel. Liebmann doubted the materialists who had turned Darwin into a creed. His goal was to keep Darwin strictly within the empirical realm and to block any leap to broader metaphysics. Liebmann’s stance is almost the opposite of Meyer’s. Meyer measured Darwin by empirical standards and found him wanting. Liebmann focused on metaphysical fallout. He did not say Darwin had broken scientific method. He even called natural selection the best account we had of species origins, and praised Darwin for amassing evidence for transformism. Darwin did not invent the idea, which is ancient, but he gave it exact form. Any fair reader of the Origin, Liebmann said, will find it enlightening. It is the thread of Ariadne through the maze of organic nature. That does not make it fully confirmed. We cannot assign a probability to it. There is still too little evidence and too much work to do. Even so, because it fits many facts and explains much, we have good reason to adopt it as a regulative guide for further research. Liebmann’s Kant cuts the other way from Meyer’s. Where Meyer waved Kant like a talisman to ward off all talk about origins, Liebmann cited Kant as an early speculator of exactly that sort, even a forerunner of Darwin. He quotes a long passage from Kant’s 1775 essay “On the Different Human Races” that sketches descent from a few prototypes. A true program for Darwinism, he exclaims. He then quotes Kant’s Anthropology, where Kant floats the thought that human beings could have emerged from apes. It is striking, Liebmann says, to find the austere idealist out in front of the notorious ape theory that got Vogt in trouble. To probe the metaphysics at stake, Liebmann poses one question. What is the relation between Darwinism and Platonism. Are they at odds, at peace, or complementary. By Darwinism and Platonism he means two worldviews, not the letter of two men’s doctrines. Darwinism stands for the attempt to explain life by mechanical laws, and in general for the Epicurean materialist line. Platonism stands for the attempt to explain life by ideal principles, that is, by teleology. Behind them stand two takes on universals. The Epicurean is a nominalist, treating universals as concepts only. The Platonist is a formalist, giving universals real standing above or beyond things. Liebmann uses Platonism broadly, to include any view that grants reality to universals. His own version is closer to Aristotle than to Plato, because, as we will see, he places universals within living things. Liebmann’s central claim is that the two worldviews can be reconciled. Platonism begins where Darwinism leaves off. Each is needed for a full account of life. Liebmann is clear about the value of pushing mechanism and matter as far as we can. To understand life we must know how it works and what it is made of, which means knowing mechanical causes and chemical stuff. He is sharply critical of the old talk of “vital force” because it places life outside the scope of universal laws of physics and chemistry. One of Darwin’s great achievements, he says, was to extend mechanism and material explanation to the origin of species. Yet, despite expelling occult forces, Liebmann thinks mechanism and matter hit a wall. They are necessary, not sufficient. They explain the workings and the components, not how and why these elements come together as a single living individual. The first causes of life, and of organic structure, lie beyond mechanical and material accounts, because those first causes are the preconditions for any living phenomenon. Natural science can explain any particular living event. It cannot explain why there are living events at all. That is a metaphysical question. Here Liebmann thinks the old notion of a vital force retains a kernel of sense. It names the leftover, the something more that mechanism and matter cannot capture. It is this extra that calls for Platonism. The extra is the form, the universal inherent in the living thing that explains its stable structure and development. We need the idea of organic form, Liebmann argues, to explain the difference between living and nonliving. In living things the form is essential and necessary. In nonliving it is inessential and accidental. The form of a living thing grows from within and is inherent. The form of a stone is imposed and could be otherwise. The organic form gathers a being’s characteristic properties into one, habits, instincts, talents, inclinations, degrees of intelligence. In stressing substantial form as central to life, Liebmann goes back to Leibniz and, ultimately, to Aristotle, where the mark of life is its characteristic form and energy, an entelechy that realises the form. Liebmann sees no clash here with Darwin, because Darwin was not trying to draw the great line between living and nonliving. On that wider question the old Platonic tradition still earns its keep. Even so, as a good Kantian, Liebmann withholds full, constitutive status from these metaphysical ideas. Substantial form and entelechy are, for him, strictly regulative. They are ideals with subjective validity for us, aids that help us make sense of life. We have no right to claim they are objectively true. Metaphysics, he says, is not a science, but a postulate and a problem. It is one thing to deny a problem, as the positivists do. It is another to recognise it and admit we cannot answer it. On this point Liebmann quietly corrects Lange, who had dismissed metaphysics as mere poetic fiction. For Liebmann, teleology and organic form are more than poetry. They still explain, even if their role is only regulative. Lange and Liebmann both call teleology regulative, but they mean different things. Lange thinks purposiveness will fade as mechanism advances, though never be fully replaced. Liebmann thinks purposiveness is irreducible and necessary, an indispensable tool for understanding organic life. Bold and clever as it is, the reconciliation has problems. Meyer blurred the line between science and metaphysics. Liebmann makes it too sharp. Can there be a rigid border between them. Do scientific theories not carry metaphysical weight, which is part of their importance. Arguably Liebmann did not fully grasp the metaphysical thrust of Darwin’s program. A central Darwinian claim is that varieties are budding species, that form grows out of selection and struggle. If so, substantial form is not needed to explain life. By reviving Aristotle and Leibniz, Liebmann was smuggling back the very tradition of fixed species that Darwin set out to break. The Linnaean system, which Darwin aimed to topple, is deeply Aristotelian. It treats species as concrete universals. In the Origin, Darwin explicitly rejected the Linnaean view that genus or species is prior to living things rather than derived from them. Linnaean classification cannot give true causes, because it focuses on form and structure, which are not basic but downstream. A true system, Darwin said, must be genealogical, showing common origins and parents. Structures are the product of inherited potentials tested in the struggle for life. Darwin replaces a formal, intellectualist picture with a genetic, historical one. Liebmann did not take that on board, and so his well meant truce between Darwin and Plato was bound to fail. All mysteries solved In 1899, worn and sixty five, Ernst Haeckel published his last will and testament, “The Riddles of the Universe.” He called himself a child of the nineteenth century and thought its end a fitting time to end his work. The book was meant to sum up his philosophy, the capstone of a naturalist’s life. It did exactly what he hoped. It sold about forty thousand copies in its first year, hundreds of thousands by the First World War, and it drew howls of protest. It is one of the most aggressive statements of a scientific, naturalistic worldview ever printed. Haeckel fires at every sacred cow in sight. If he was leaving the old world, he wanted to level it on the way out, and ground a new twentieth century on scientific morality and a scientific religion. At its core the book sets out Haeckel’s monism, what we would now call naturalism, the claim that everything is in principle explainable by natural law. The enemy is dualism, the claim that there are limits in principle to science, alleged islands of life or mind beyond nature in a supernatural realm. Haeckel presents monism as the philosophy of science, the worldview backed by the achievements of the century that had done more for knowledge than all previous centuries combined. He is so confident that he says science has solved all the great riddles except one, and that the last one, free will, is not a real riddle, since free will does not exist and is not a fit object for science. A close friend, Emil du Bois-Reymond, had listed seven great riddles, the essence of matter or force, the origin of motion, the origin of life, the apparent design of nature, the origin of sensation, the genesis of consciousness and language, and free will. Haeckel announces that natural science has cracked the first six and that the seventh is a non issue. It is a breathtaking claim. Put in context, it is a reaction to what Haeckel saw as the timidity and betrayal of old allies. They had lost their nerve. Where once they saw questions that science could answer, they now saw limits it could not cross. Though pitched as a philosophy for the future, the book is really a rearguard action, the last stand of an old style naturalist who felt abandoned. He wrote it to vindicate himself against colleagues who had been proud mechanists in youth but had turned dualist in age, Rudolf Virchow, Karl Ernst von Baer, Emil du Bois-Reymond, and Wilhelm Wundt. They had worked with Haeckel to purge teleology and vital forces from embryology, physiology, and psychology. Later they declared the mechanist program unworkable. Haeckel called them traitors to the cause and set out to defend it alone. The title itself is a counter to du Bois-Reymond’s “The World Riddles.” Du Bois-Reymond meant his riddles to be warnings to an overconfident naturalism. Haeckel wanted to show they were hollow, arbitrary, and artificial limits to scientific progress. Besides laying out monism, the book attacks every face of dualism and the moral and religious interests behind it. The main targets are the three core dogmas of metaphysics, God, freedom, and immortality. All three, he says, are incompatible with monism, because they presuppose a realm beyond nature. Science has already shown, one, theism rests on anthropomorphism, the projection of human wishes onto reality, two, freedom does not exist because everything happens by natural necessity, and three, the soul is mortal because it depends on the brain and body. Monism is therefore atheism, determinism, and, as Haeckel calls it, psychomortalism, the mortality of the soul. He does not mind calling monism pantheism, the view that God and the world are one and the same. He notes that pantheism has always been the worldview of modern science, then reminds readers, with Schopenhauer, that pantheism is often a polite name for atheism. In the great conflict of science and religion, reason and faith, Haeckel takes a hard line for science. There is no halfway house in which reason can justify faith. The deeper we push inquiry, the more we find not only a lack of evidence for God, freedom and immortality, but evidence against them. They are simply false. There can be no compromise. The old faith must go, and people must learn to live without the old gods. Faith without possible verification is superstition. He concedes religion’s moral and practical value, but insists that any creed must be grounded in reason, not in church authority. He calls for a palace of reason, with a new trinity of truth, goodness and beauty in place of Father, Son and Holy Ghost. Not least, Haeckel takes aim at the Neo-Kantians. He attacks Kant’s limits on mechanical explanation in biology. How could Kant have foreseen, he jeers, that the Newton of the blade of grass would appear in Darwin, who showed mechanism could explain the origin of life. Kant’s worst mistake, he says, was his dualism, especially the move to rescue God, freedom, and immortality by practical reason. What Kant barred at the front door of theory, he smuggled in at the back door of practice. The split between theoretical and practical reason is, for Haeckel, a trick to preserve religion. The claim that these beliefs are neither provable nor refutable is wrong. Science has piled up evidence against them. In trying to save them for moral use, the Neo-Kantians show they are out of touch with science. Their movement, he says, rests on this failed strategy. He then hammers their reverence for Kant in a long footnote, listing Kant’s lack of medical training, his narrow travels, his limited horizons, to ask if this is the right sage for a new century of science. In spirit and stance, “The Riddles of the Universe” reads like a fresh materialist manifesto, a late successor to Büchner’s “Force and Matter.” Many contemporaries saw it that way, a blast from the past. Haeckel tries to separate himself from the older materialists. They knew nothing of Darwin and science had moved on. More important, he insists monism is not materialism. Where materialism denies mind and dissolves the world into dead atoms, monism affirms mind and treats matter as living forces. He identifies his monism with Spinoza’s, where mind and body are two attributes of one reality. That identification is a smokescreen. Haeckel also defends a defining materialist thesis, that the soul is nothing but a name for a sum of brain functions. That is reductive materialism, not Spinoza. For Spinoza, mind and body are equal and independent attributes of one substance. Neither reduces to the other. There is, however, another monism peeking out of Haeckel’s book, more like vitalism, the idea that everything is alive. True to a vital materialist streak, he treats matter as active force, not inert extension, and ascribes feeling and willing to all atoms. He never works out this line, which could have brought him closer to Leibniz and to the philosophy of identity in Schelling and Hegel. He leaves his view wavering between full materialism and a vital monism. His Neo-Kantian critics pounced on the tension. Restoring mysteries Since Haeckel targeted the Neo-Kantians, they answered in kind. Two major replies appeared in 1901, Erich Adickes’s “Kant versus Haeckel,” and Friedrich Paulsen’s “Ernst Haeckel as Philosopher,” published in his “Philosophia militans.” Both set out to criticise scientific dogmatism, meaning the uncritical move to base metaphysics on natural science. That cuts to the nerve of Haeckel’s claim to speak for a philosophy of science. For the Neo-Kantians, there is no such thing as a philosophy that simply repeats science. Paulsen’s tract, as philosophy, is thin. It targets Haeckel’s habits more than his theses. He wants to show that Haeckel is not to be taken as a philosopher. He laments Haeckel’s tendentious reasoning, shallow evidence, and confusions, which make it hard to pin any firm doctrine on him. He hates above all the dogmatism, the air of having solved what he has not begun to examine. Haeckel judges others without studying them, he says, and misses the depth of the problems he claims to solve. All this is fair, but Paulsen does not move the discussion on. He does not answer Haeckel’s serious challenges, for example the attack on Kant’s split between theory and practice. Instead he spends pages proving Haeckel is a bad Kant scholar. Who expected otherwise. Later, in a calmer postscript, Paulsen concedes something important. He credits Haeckel for fighting for Darwin when it was unpopular, which explains some of the polemical tone. In that cooler mood, he makes one sharp point. He notes the deep tension in Haeckel’s monism. On the surface it is plain materialism, of a piece with Büchner and Vogt, though Haeckel lacked the candour to admit it. Underneath it is organicism or vitalism, the claim that reality at bottom is alive. That comes out whenever Haeckel says feeling and willing are inherent in all things. If the outer face of things is motion and extension, their inner face is feeling and thought. That puts him, at moments, in the line of Spinoza, Bruno, and Giordano Bruno’s followers. Had he followed that current, Paulsen says, he would have ended near his contemporary Gustav Fechner, who saw all reality as alive. Instead Haeckel slides back to materialism by reducing life to matter. Adickes’s book is very different. Rather than belabour Haeckel’s style, he goes for the main issues and states his own view. “Kant versus Haeckel” is not a blanket defence of Kant. Adickes warns that he does not accept everything in Kant. What he does take over is Kant’s critical, epistemological stance. That stance is the bar he will hold Haeckel to. On that standard, the verdict is clear. Kantian criticism, or more broadly, a reflective critique of knowledge, should have been the foundation of the whole book. Had it been, Haeckel’s book could not have been written. From start to finish, Adickes says, it is dogmatic metaphysics, a new dogmatism that claims to rest on science rather than pure reason, but dogmatism all the same. Kant’s old sentence fits Haeckel. The dogmatism of metaphysics, the prejudice that one can make progress without a critique of reason, is the true source of unbelief and confusion. Like Paulsen, Adickes reads Haeckel as a materialist and dismisses the evasions. The tell is the reduction of mind to matter. Haeckel runs through all three classic reduction moves. He treats thought and feeling as properties of matter manifest under certain conditions, he identifies thought and feeling with brain motions, and he derives thought and feeling as effects of material causes. Since his philosophy is materialism, it inherits all the old objections. Adickes is amazed Haeckel learned so little from the materialism controversy. The weaknesses that Lange exposed in Büchner, Vogt, and Moleschott apply to Haeckel too. The big one is that there is no evidence for matter in the materialist sense, a thing existing in space and time with all the properties we perceive, even when no one perceives it. Physiology and psychology show how our cognitive processes shape what we know. We cannot treat matter as a simple given of sense. Rather than say reality in itself is matter, we should say the opposite. The physical is derived from the psychic. Matter is a product of mind, existing as a state of consciousness. This is epistemological idealism, the view now linked to Kant’s name. Adickes does not think this point alone defeats every reading of Haeckel. He shares Paulsen’s sense that there is also a hidden vitalist strand in Haeckel, which appears when he ascribes feeling and desire to all matter. On that claim, Haeckel has no observational support. It is as much an act of faith as belief in God and immortality. If we stress this vitalist side, Adickes says, we can make better sense of Haeckel’s nods to Spinoza. Then reality has two equal and independent sides, an inner, where things feel and desire, and an outer, where they are motion and extension. That would be a fair version of Spinoza’s dual attribute view. Adickes thinks this doctrine is implicit in the book and regrets that Haeckel did not develop it, held back by his taste for materialism. Like Paulsen, he concludes that Haeckel’s monism is a monster, a confused fusion of materialism with the vitalist philosophy of identity in Schelling and the nature philosophers. Far from refuting Kant’s doctrine of practical faith, Adickes says, Haeckel confirms it. Kant’s old strategy, to deny knowledge so as to make room for faith, still holds. Had Kant read Büchner and Haeckel, he would have said again what he wrote in the Critique of Pure Reason, that beyond the world as we experience it lies an empty space, and that whoever sails off the little island of experience into the open sea of reality itself can do so only in the little boat of faith. For Adickes the thing in itself is the outcome of transcendental idealism, and it gives shelter to the whole realm of faith. Haeckel has not refuted God, freedom, and immortality, because they are about the transcendent. They sit above proof and refutation. Theoretical reason must be agnostic. The realm of faith is as broad as everything that cannot be proved or disproved by reason or experience. That includes all metaphysics, including Haeckel’s own. It is naive to think first principles flow straightforwardly from observation and experiment. These never prove universality and necessity. Adickes defends Kant’s practical faith, though he gives it a very personal reading. What one believes is a matter of individual choice and feeling, justified pragmatically by the needs of life. He drops the moral argument from the categorical imperative. His complaint about Haeckel is not that Haeckel ignored morality, but that he ignored how vital faith is for many people. Who was Haeckel to strip people of belief in God and immortality when that gave them comfort in hard times. Haeckel’s atheistic, materialist worldview is itself an act of faith, because it goes beyond the limits of experience. Adickes ends by asking why Haeckel’s book was so popular. He lists four reasons. People overestimate science. There is a hunger for an all in one worldview. Radical poses are fashionable in intellectual circles. Anti clerical and anti Christian feeling is rising among the educated. It is a plausible diagnosis of the mood of the age, and it leaves one wondering whether, despite the Neo-Kantian attacks, the times were on Haeckel’s side. Introduction to the new establishment The 1860s were the breakthrough of Neo-Kantianism. The 1870s were its consolidation. Through that decade, Neo-Kantianism became the leading movement in German philosophy. The facts, gathered by Klaus Christian Köhnke, are telling. After 1862, writings on Kant grew each year at a geometric rate, and Kant lectures in the 1870s more than tripled those of the 1860s. By the late 1870s there was at least one Neo-Kantian professor in ten major German speaking universities, more than any other school. From the 1870s to 1900, Kant was so dominant in journals and lecture halls that it is no exaggeration to call this the Neo-Kantian period of German university philosophy. What explains the success. Politics and institutions helped. The more liberal climate of the 1870s mattered. The legislation of 1873 increased church state separation. Academic life had more independence from church control. The bad old days of the 1850s were gone, when a reference to David Friedrich Strauss or a whiff of pantheism could cost you your chair. The growth of the university system mattered too. After unification in 1871 there was a hiring boom. New universities opened, and old hiring gaps from the 1850s had to be filled. These were years of opportunity for talented young scholars. In the 1850s a candidate waited on average fourteen years to become an ordinary professor. In the 1870s the wait fell to eight. Between 1876 and 1878, Liebmann, Cohen, Riehl, and Windelband all became ordinary professors. Those factors could have lifted any movement. What lifted Neo-Kantianism in particular were its intellectual selling points. First, it was a powerful bulwark against materialism. Second, it offered the best available story about philosophy’s role in a scientific age. The line that philosophy should chiefly examine the logic of the sciences seemed to guarantee its survival. It gave philosophy a distinct vocation that science could not absorb, and it made philosophy a helpful partner to science. For these reasons Windelband, Riehl, and Paulsen kept pressing the 1860s view, first worked out by Fischer, Zeller, and Meyer. Old rivals were also weakening. Hegelianism was fading fast. Lotze and Trendelenburg tried to save the idealist legacy, its teleology and organic view of nature, but they were fighting a rear guard action. Materialism was declining too. Lange says in the second edition of his “History of Materialism” that talk of Darwin had completely overshadowed the old materialism. Büchner still had readers, but new editions no longer caused an outcry. Vogt was rarely mentioned. Moleschott was almost forgotten. The old dragon of the 1850s lay slain, with two victors standing over it, Helmholtz and Lange. Yet the 1870s also reveal cracks in the foundation. There was a tension in the Neo-Kantian picture of philosophy that would fuel controversy in the late 1870s and 1880s. The picture rested on two inconsistent ideals, that philosophy be autonomous as a discipline in its own right, and that it imitate the model of the natural sciences. The more philosophy copied science, the more it became like science, lost its autonomy, and sped toward obsolescence. This was most obvious in psychology. Psychology was meant to model scientific epistemology, but the more scientific psychology became, the less it needed philosophy. Then philosophy became superfluous. A bigger challenge hit the definition of philosophy as epistemology. As this definition took hold, doubts grew that it was too narrow. If philosophy is simply the second order analysis of scientific reasoning, then it gives up its old role as a worldview that answers basic questions about meaning and purpose. Those questions have been central since antiquity. Should they be ignored. The risks of ignoring them were already clear in the 1870s, in the popularity of Schopenhauer and Hartmann. If the Neo-Kantians stuck too rigidly to epistemology, they would lose the public. Their work would become esoteric, for specialists only, which is a first step toward irrelevance and then toward obsolescence. A fragile alliance One defining feature of Neo-Kantianism in the 1870s was its close alliance with positivism. In the last quarter of the century, positivism became a force in German philosophy. Its leading voices included Richard Avenarius, Ernst Laas, Ernst Mach, and Eugen Dühring. Their main platform was the “Quarterly for Scientific Philosophy,” edited by Avenarius, Karl Göring, Max Heinze, and Wilhelm Wundt. The alliance was mostly tacit and tactical. Neo-Kantians wrote for the journal. Friedrich Paulsen, Hans Vaihinger, Otto Liebmann, Eduard Zeller, and Wilhelm Windelband all contributed. For a time Alois Riehl even helped edit. On the face of it, the journal’s program fit Neo-Kantian ideals. Avenarius’s opening essay promised a scientific philosophy, whose task was to examine the logic of the sciences, and to tackle traditional problems only as far as they were empirically testable. Many old problems, he said, were pseudo problems because they went beyond experience. Hostility to metaphysics, experience as the limit of knowledge, philosophy as the logic of science, all this sounded Kantian. But the alliance was flimsy. It was a marriage of convenience against common foes, the metaphysicians, Lotze and Trendelenburg, the old church party, and the new irrationalists, Schopenhauer and Hartmann. It worked only by pretending away deep differences. Neo-Kantians were critical of the positivists’ extreme empiricism, their naive faith in given facts, and their claim that science has no metaphysical presuppositions. These worries surfaced in the later 1870s. In the first volume of his “Philosophical Criticisms” in 1876, Riehl quietly took aim at positivism when he criticised Locke and Hume’s empiricism. By 1878 Karl Schmidt said out loud that positivism is false criticism because of its naive empiricism. By the 1880s the rift widened. In 1884 Liebmann tossed a bomb into the positivist camp with his “Theories at the Turning Point.” The biggest differences were not about knowledge but about the identity of philosophy. In the late 1870s the Neo-Kantians grew restless with the strict epistemology only line, which ruled out inquiry into meaning and value. You can see the shift in several moves, in Volkelt’s call to renew Kantian ethics, in Windelband’s turn toward ethics, in Riehl’s renewed attention to practical philosophy, and in the refocus of “Philosophical Quarterly,” now devoted to systematic knowledge of the highest and most general ideas and aims of humanity. The more they pushed beyond narrow epistemology and into ethics and practice, the further they moved from positivism. Positivists had their own ethics, empiricist in spirit, but the Neo-Kantians distrusted empiricism in morals even more than in theory of knowledge. They were convinced it slides into relativism and nihilism. As Paulsen put it, it is a firm axiom that crude empiricism leads to materialism, then to full scepticism, and finally to moral nihilism. Some historians claim the break with positivism was triggered by the assassination attempts on Kaiser Wilhelm I in May and June 1878, which fed anti socialist panic and harsh laws. On that reading, the Neo-Kantian turn to the practical was an attempt to devise an authoritarian ethics to keep the masses in line. There are problems with that story. We lack evidence about the politics of many Neo-Kantians in the 1870s, and the turn to practice predates 1878. More to the point, the practical turn was driven less by fear of socialism than by the public success of pessimism in the 1860s and 1870s. Schopenhauer and Hartmann had seized the old philosophical ground, the question of existence and the value of life, while Neo-Kantians and positivists were lecturing on the logic of science. If a philosophy does not speak to the public, its books do not sell and its lecture halls do not fill. Livings and reputations depended on both. From psychology to epistemology The 1870s mark a sea change in reading Kant. Herman Cohen, Alois Riehl, and Wilhelm Windelband broke with the old psychological reading, first framed by Fries in the 1790s and long treated as orthodoxy. They insisted that the critical philosophy is first of all epistemology. Its concern is the validity of synthetic a priori knowledge, not the causal origins of our beliefs. Focus shifted from the quid facti, the facts and causes of knowing, to the quid juris, the grounds that make judgments true and inferences valid. The psychological interpretation was now treated as a mistake, built on the false assumption that Kant’s main task was to answer a question about origins that, on the texts, he did not set himself. This new orthodoxy cast transcendental inquiry as second order, a reflection on our knowledge of the world, not on the world itself. Psychology, by contrast, is first order, since psychic events, like physical events, are within the world. There is a large logical gap between talking about the world and talking about our talk about the world. Cracks in the psychological reading had already opened in the 1860s. Fischer and Liebmann noted that Kant’s transcendental project cannot be just psychology, because it investigates the possibility of all empirical knowledge, of which psychology is only one part. If transcendental philosophy were only empirical psychology, it would be circular, presupposing what it is meant to examine. Even so, the authority of the sciences kept people from pushing the implication home. There was no dramatic revolt, just a slow death for psychologism. It was never a clean break. Cohen, Windelband, and Riehl had been enthusiastic students of Herbartian psychology in their youth and kept a role for psychology in understanding cognition. They wrote for Steinthal and Lazarus’s “Journal for Folk Psychology and Language Science,” which aimed to expand psychological study to group life and culture. Even as they stressed the sui generis status of logic, they held that logical rules regulate and refer to psychic events, and they did not forget Fries’s old point about the difference between the order of discovery and the order of justification. Only in the 1880s did Cohen, Windelband, and Riehl drop their interest in empirical psychology and devote themselves to the logical, epistemological side of Kant’s project. Part of the slow turn has to do with psychology’s own ambiguity. Some psychologists, such as Fechner and the Webers, took psychology to be a straightforward natural science, mapping causal relations between psychic or psychophysical events by observation and experiment. Others, most notably Brentano and the young Dilthey, saw psychology as something richer, an inquiry into psychic contents and their meanings as well as events and causes. On that broader view the gap with epistemology narrows, since the logic of intentional contents is the heart of epistemology. The confusion shows up most clearly in the young Alois Riehl, who first defined philosophy as a science of consciousness, then recast it as psychology in a new sense, the interpretation of contents rather than causes, and finally drew a sharp line between philosophy and psychology understood as the search for natural laws of mental life. Why did the change come when it did. There is no simple answer. Partly it turns on the shifting thoughts of particular figures in the late 1860s and early 1870s. Partly it reflects a broader cultural mood. Hard facts are thin. What is clear is that a young Herman Cohen was central to the turn. The preface states the aim with complete clarity. Cohen is not offering a new system. He means to defend Kant against misunderstandings, above all against Trendelenburg’s claim that the proofs for the subjectivity of space and time leave a gap. The book is conceived as a careful reconstruction of Kant’s argument, not a free retelling. Cohen asks the reader to judge him by fidelity to Kant’s own steps. He warns that psychology in the empirical sense will not help here. The inquiry is into grounds and validity, not into causes and origins. That signal sets the course for everything that follows. The plan of the first edition mirrors Kant’s path but with a polemical edge. It begins where the dispute bites, with the transcendental aesthetic. Cohen lays out why space and time are pure forms of intuition. He stresses that Kant’s point is not about what we often experience, but about the necessary form in virtue of which anything can be experienced as outer or inner at all. Against Trendelenburg he insists that the proofs are not inductive generalisations from psychological facts. They are demonstrations from conditions of possible experience. Cohen spends time on the famous Third possibility and explains why it is ruled out. If space and time were both subjective forms and also features of things in themselves, the very distinction between appearance and thing in itself would collapse, and with it the Copernican turn. From the aesthetic he moves to the synthesis of imagination. Here the book shows its distinctiveness. Cohen makes synthesis the living nerve of objectivity. Objects are not given as completed units and then judged. They are constituted through the unity of synthesis under rules. The threefold synthesis, apprehension in intuition, reproduction in imagination, and recognition in the concept, are not psychological episodes but moments in the structure of objective experience. Cohen presses the point that only a transcendental reading preserves their necessity. Read as psychology they become habits and associations and the argument loses its force. He then turns to the categories and their deduction. The strength of the treatment is its refusal to reduce the deduction to a catalogue. Cohen follows the line from the unity of apperception to the objective unity of experience. The I think is not a separate inner item. It is the function by which the manifold is combined according to rules. The categories name these rules in their pure form. Against the temptation to treat them as inborn ideas, Cohen gives them an epistemological sense. They are conditions of the possibility of experience that can be exhibited in the lawful structure of the sciences. A striking feature of the first edition is its insistence on empirical realism within transcendental idealism. Cohen dwells on Kant’s claim that appearances are not illusions. There are external things and they are given in space. What is ideal is the form, not the existence of objects. This clears away the caricature that Kant denies reality to the world. It also answers the realist who thinks only a thing in itself can anchor objectivity. For Cohen the anchor is the lawful form of experience itself. Throughout, Trendelenburg is the silent partner. Where needed, he becomes explicit. Cohen shows that Trendelenburg reads objectivity as correspondence with things in themselves, and so misses the revolution in the concept of object. He also shows that importing a physiological story of the senses into the transcendental proofs is a category mistake. It answers the wrong question. Where Fischer had asserted these points, Cohen strives to demonstrate them step by step. The closing chapters of the first edition sketch the principle behind Kant’s method of thought. Cohen calls it the transcendental method. It starts from a fact of science, above all the apodictic character of Newtonian mechanics, and asks for its conditions. It does not try to derive science from first principles, nor to secure it against all possible doubt. It takes science as a given achievement and explicates the forms that make it possible. Paul Natorp later rightly saw in this the seed of the Marburg programme. The seed is already fully visible here. It is worth seeing why this first edition matters in its own right. Because it is shorter, the line of argument is lean and direct. Later expansions added breadth, but also new themes that can blur the original intent. Here the intent stands out. Defend the Copernican turn as a change in the concept of objectivity. Read the a priori as conditions of validity, not as mental furniture. Keep psychology in its place as a useful empirical study that decides nothing about truth and necessity. Given that the archives do not help us much, it is striking how much the text itself reveals about the forces that shaped it. The materialism controversy is present in Cohen’s defence of empirical realism and his refusal to let natural science be patronised by metaphysics. The Fischer and Trendelenburg dispute is present in the precise framing of every proof in the aesthetic and the deduction. The Herbartian past is present as a foil. Terms are sometimes shared, but the meanings are turned. Priority becomes logical rather than temporal. Association gives way to transcendental affinity. Form and content are no longer feeling and object, but rule and manifold within one order of experience. This also explains the speed of the summer of 1870. Cohen did not change his mind on a whim. The earlier essays already show him groping toward an epistemological reading. The dispute gave him the occasion and the focus to write it out as a system. Letters report the flow. By mid July the space doctrine was in place. By early August the transcendental logic was underway. By early October the defence was complete in outline. The one year delay to print hides the intensity of that season, but the preface date reminds us when the thinking was done. Taken together, the first edition offers a clear picture of the new epistemological interpretation. It is faithful to Kant’s text without being pedantic. It is historical without anachronism. It is systematic without metaphysics. And it sets the template for Marburg method by beginning from the fact of science and working back to its conditions. Windelband draws the line with care. Psychology describes how we in fact think, feel, choose. It collects regularities of mental life and explains them by causes. Philosophy, by contrast, asks whether our thinking is correct, our willing is right, our judging is true, and it justifies the standards by which such questions can be answered. Metaphysics, finally, concerns what there is. If philosophy is folded into psychology, the question of reasons becomes a question of causes and validity disappears. If philosophy is absorbed by metaphysics, norms are treated as beings among beings and again their distinctive status is lost. The crisis of obsolescence is thus resolved by restoring philosophy to its proper seat as the tribunal that determines validity, not as a laboratory of mental facts nor as an inventory of entities. The centre of gravity is the concept of validity. Windelband inherits from Lotze and Herbart the contrast between being and validity and he turns it into a guiding thread. Truth is not a picture that resembles its object, it is the holding of a judgement under a rule. Rightness is not a psychological compulsion to act, it is the holding of an act under a law. Beauty is not a sensation of pleasure, it is the holding of an intuition under a canon. In each field we meet claims to universal standing. Science claims necessity for its laws, ethics claims unconditionality for its commands, art claims exemplary force for its standards. Philosophy identifies, articulates and criticises the norms that would make such claims defensible. This immediately raises the hard question that Windelband does not evade. Where do these norms come from and what sort of thing are they. He refuses a metaphysical story that would place them in a supersensible realm. He also rejects psychologism which would reduce them to customary habits or natural propensities. Their source is practical and theoretical reason itself. They have no existence apart from our activities, yet they bind those activities by an authority that is not the same as force or custom. To say that a norm holds is to say that a claim can be justified by reasons that any competent agent could in principle recognise. The universality at stake is that of a community of rational justification, not that of a transcendent object and not that of a statistical average. From here Windelband develops the well known triad. Logic deals with the norms of true judging, ethics with the norms of right willing, aesthetics with the norms of correct forming and appreciating. He insists that this tripartition is not a mere taxonomic convenience. It marks three irreducible modes of normativity. Attempts to absorb one into another, for instance to reduce ethics to psychology or aesthetics to feeling, always end by confusing causes with reasons and preference with validity. The unity of philosophy is not found by collapsing these regions but by recovering the common structure of norm governed activity in each. He is alert to the charge of relativism. If norms are not discovered as independent things, and if cultures plainly diverge in their canons, does not normativity dissolve into historical contingency. Windelband’s answer is twofold. First, description of diversity belongs to history and psychology, but the question whether a standard is valid is different in kind. Second, the very practice of criticism presupposes a claim to more than local assent. To criticise is to appeal from habit to rule and from rule to reason. The task of philosophy is not to legislate a final code, it is to make explicit the commitments that are already at work when we claim truth, rightness or beauty, and to test those commitments for coherence and scope. That task may vindicate only form and procedure rather than substantive content, but even form has bite, since it can rule out whole families of standards as inconsistent or question begging. This is the point at which Windelband’s conception intersects with his work on history. The famous distinction between nomothetic and idiographic inquiry protects history from an alien standard without denying its rationality. Nature is known under laws, hence explanation by subsumption under general rules. History is known under values, hence understanding by individuation under significance. Philosophy as critique of norms can therefore justify different canons of validity for different domains without retreating to relativism. The validity at stake in a good historical account is not predictive law, it is adequacy to meaning and worth within an objective framework of relevance. That framework is not a private taste, it is anchored in shared cultural values whose claims can themselves be argued about and refined. Windelband nevertheless recognises limits in a purely critical conception. Norms must be more than bare forms if they are to guide life and culture. This concern explains his later oscillation on world view. Early he warns that Kant did not give us a world picture, only a theory of normal consciousness. Later he concedes that philosophy cannot live by critique alone. Human beings need orientation. Without a regulative synthesis the disciplines splinter and culture drifts. He therefore admits a chastened metaphysics, not as dogmatic knowledge of supersensible objects, but as a reflective articulation of the highest and most general ideals that unify our activities. In this sense a world view is not a rival to critique but its completion. It gathers logic, ethics and aesthetics into a coherent image of the good life and a humane culture, always under the discipline that the claims it makes remain accountable to reason. Against this background Windelband’s divergence from Cohen becomes clearer. Both reject psychologism and defend the quid juris. Both insist that the a priori names conditions of validity, not inner furniture or outer archetypes. Yet Cohen keeps the model of exact science at the centre and builds his method around the analysis of mathematical physics. Windelband widens the field. He places side by side the sciences of nature and the sciences of spirit and he shifts the focus from construction to evaluation. For Cohen the guiding maxim we know only what we in some sense put into objects drives the deduction of categories. For Windelband the guiding maxim is truth is normativity of thinking, and its counterparts in willing and forming. The first is a theory of constitution, the second a theory of justification. This shift affects their handling of the thing in itself. Cohen tends to neutralise it into a limiting concept in order to secure a fully immanent account of objectivity. Windelband has less interest in that controversy. The decisive move for him is to relocate the criterion of objectivity in rules of justification rather than in correspondence with a noumenal order. Whether or not there are things in themselves, the mirror model is mistaken. What matters is the norm that entitles a judgement to claim validity, and that norm is explicable without a traffic between pictures and prototypes. Finally, Windelband’s rehabilitation of philosophy lies in the public role he assigns it. If philosophy is the science of norms it has an office that no other discipline can assume. It does not compete with physics or psychology. It clarifies their claims to validity. It does not dictate to ethics or art. It makes explicit the standards implicit in their best practice and tests them. In an age where the special sciences multiply and fragment, such a role is not ornamental. It is the condition under which culture can remain intelligible to itself. He rejects any suggestion that the aim of knowledge could be read straight off its causal history. Causes explain how a belief arose, they do not show whether it ought to be held. In the early treatise this distinction is present more as a tension than a settled doctrine. He wants psychology in the room because thought is an activity, yet he also wants a standpoint from which activity can be judged. The result is a three voiced inquiry. Logic articulates forms, psychology supplies the mechanism that moves us through those forms, metaphysics frames the claims about being that our best judgements seem to commit us to. The young Windelband is still searching for the right balance between these voices. The search turns on the problem of certainty. He thinks a purely formal logic will never still the sceptic, because form alone cannot tell us why the intellect should commit itself here rather than there. He thinks a purely psychological story will never suffice either, because the fact that we are caused to believe something does not make it worthy of belief. Hence the initial syncretism. He wants a route from description to prescription without confusing the two. He probes cases where logical form, psychological compulsion and metaphysical claim pull apart. Habit may incline us to inductive leaps, logic may license only a narrower step, and metaphysics may demand clarity about what sort of being our conclusions presuppose. In these moments the need for a governing concept of validity first comes into view. Lotze and Sigwart help him name that need. From Lotze he learns to mark the difference between what is and what holds, between existence and validity. From Sigwart he learns to take seriously the norm character of logical principles without turning them into innate ideas. These lessons are not yet the later doctrine, but they reshape the project. If logic is a body of norms, then psychology cannot found it, at most psychology can describe the conditions under which those norms are followed or ignored. If metaphysics speaks about what there is, then it cannot legislate the standards by which true claims about what there is are made. The path opens for a conception of philosophy as the science that makes those standards explicit and assesses their reach. The pull of contemporary science remains strong. He reads the new psychophysics with respect, and he grants that it confirms a central result of the critical turn, namely that what we perceive is co-shaped by our forms of apprehension. Yet he will not let this result consume its parent. If construction reaches that far, the question of objectivity becomes sharper, not softer. What entitles the sciences to universal standing if their content is so conditioned. The answer cannot be another experiment, since experiments already presuppose rules of inference and measurement. The answer must name the norms in play when we count a finding as a finding. This is the bridge from the early, mixed epistemology to the mature, normative one. He tests the bridge on the old battlefield of foundationalism. He abandons the dream of a single axiom from which all knowledge may be derived, but he keeps the more modest claim that some commitments stand as conditions of the possibility of inquiry. They are not proven by prior premises, rather they are shown by the role they play. They function as rules without which there would be no judging, no proving, no refuting. To display that role is not to reduce them to habit. It is to exhibit their necessity for the very practices by which we check and correct ourselves. At the same time he continues to refine the place of metaphysics. He will not call validity a thing, nor place norms in a realm of entities. He will, however, allow that reflection on what must be the case if our practices are to make sense has metaphysical consequences. It tells us that reality, as the sciences grasp it, is always already filtered by rules of synthesis and measure. It tells us that persons, as moral life understands them, are bearers of responsibility under rules that do not collapse into description. These are modest consequences, but they matter. They free philosophy from the impossible task of inventing the world, and they keep it from the equally impossible task of surrendering to bare fact. The idiographic and nomothetic distinction crystallises the same thought on the side of method. Nature is investigated under laws, history under values. The point is not that history is subjective or arbitrary, rather that its canons of adequacy are different. Explanation by covering law does not fit the kind of understanding that gives an event significance in a life or a culture. A good historical account is answerable to reasons, but the reasons are about meaning and worth, not just about frequency and prediction. Here again the thread is normativity, the authority of a standard within a practice. By the mid 1880s the pieces lock. Philosophy is not a rival science, and not an overseer that dictates results, it is the critique that clarifies the standards by which results claim validity. Where the early Windelband sought certainty against the sceptic, the later Windelband seeks legitimacy against the relativist and the reductionist. Legitimacy does not come from an inventory of causes, and not from an appeal to a supersensible storehouse of forms, it comes from the public force of rules that any competent agent can in principle recognise and use. This leaves intact the worry that rules can be parochial in disguise. He does not deny the danger. He treats history as the antidote. We learn what our rules do by watching them at work in science, art and morality across time. The lesson is not that validity reduces to local custom, but that content cannot be fixed in the abstract. Critique needs material. That is why the later Windelband warms to Hegel without becoming a Hegelian. He can grant that reason discloses itself historically while still denying that the march of events carries necessity of the logical kind. The final adjustment is ethical. Freedom is treated neither as a ghostly power that breaks laws nor as an illusion that laws produce. It is the name we give to the way reasons become our causes. When we take a norm as our reason and act on it, the act belongs fully to the order of nature, yet it is also answerable to appraisal. Responsibility needs nothing more mysterious. It needs practices of address and correction that presuppose both law and norm, both explanation and appraisal. This is all that is required for the bridge between the natural and the normative to bear weight. Seen whole, the development is steady. Syncretism gives way to a division of labour, and the division of labour is then stitched back together by the notion of validity. Psychology remains, but it describes. Metaphysics remains, but it follows. Logic leads, but as critique rather than as invention. In this settlement philosophy is neither obsolete nor imperial. It is indispensable because only it can say what our claims to truth, goodness and beauty amount to, and what would entitle us to make them. Windelband always thought of logic and psychology as addressing different sides of the same process, two ways of understanding how we think and know. Logic asks about the validity of thought, psychology about its causes. He explained the distinction through two kinds of necessity. In psychology, necessity means causal compulsion: thinking happens according to natural laws, and in that sense every mental act, whether sound or mistaken, is equally necessary because it follows those laws. In logic, necessity has an entirely different sense. It refers not to what must happen, but to what ought to happen if we are to think correctly. Logical necessity has more in common with moral necessity than with causal necessity. Logical laws are imperatives, not descriptions. They tell us how we should reason if we want our thinking to be valid. We can, of course, make these laws into habits so that they become part of our natural mental life, but that does not change their status. Even if they come to operate automatically, they remain rules we ought to follow, not merely processes that happen. Confusing the two leads to the mistake of thinking that logic is just psychology under another name. In his early essay On Certainty, Windelband goes further, describing the laws of logic as hypothetical imperatives. They tell us what to do if we wish to know. They lay down the formal conditions for the acquisition of knowledge. In that sense, they are what he calls “laws of ends,” or norms. This is the first time he uses the term “norms,” which would later become central to his philosophy and to the entire Southwest school. For Windelband, then, logic is justified teleologically: its rules are justified because they are the necessary means to achieve the end of knowledge. If a rule really is necessary and sufficient for knowing, that is all the justification we can give for it, and all that is required. Yet even as he stresses this normative view, Windelband retains a place for metaphysics, especially in his early writings. As a student of Lotze, he is convinced that epistemology ultimately leads into metaphysics. The question of knowledge conceals within it, as he writes, the puzzle of existence itself. The psychological aspect of epistemology naturally opens onto the metaphysical, because once we treat knowing as an event, as something that comes into being, we must ask what it means for such an event to occur at all. Understanding a process requires an account of being. He agrees with Herbart that psychology presupposes metaphysics, since it depends on assumptions about what sort of reality the mind and its objects have. He gives another reason for linking epistemology and metaphysics: the analysis of knowledge always comes up against the given, the raw content of sensation that cannot be derived from the laws of our subjectivity. Explaining what this given is, and how it stands in relation to experience and to other things, is the task of metaphysics. On this point, Windelband again follows Herbart, who made the ultimate elements of experience the subject matter of metaphysics itself. For Windelband, then, metaphysics culminates in the theory of knowledge, because knowledge is the highest form of being. In the early 1870s, philosophy thus appears as a deliberate synthesis of logic, psychology, and metaphysics. Logic and ethics are already understood normatively, but the normative aspect is only one strand in a much wider enterprise. Before he could reach his later conception of philosophy, he would have to abandon this early syncretism, removing psychology and metaphysics from the epistemological core. The first sign of that shift appears in his 1874 review of Christoph Sigwart’s Logic. Here Windelband shows sympathy for Sigwart’s project of a purely formal logic. The key question becomes how logic can stand on its own as an autonomous discipline, independent of both psychology and metaphysics. He likens these two fields to Scylla and Charybdis, dangers between which logic must steer if it is to remain independent. Psychology, he argues, cannot provide the concept of truth. From the standpoint of natural law, all thinking, whether right or wrong, follows the same causal patterns. Logic, however, is defined precisely by its concern with truth and the means of attaining it. Metaphysics, by contrast, raises questions that cannot be settled. The moment we ask what truth is in a metaphysical sense, we are lost in speculation. Hence, logic should avoid metaphysics as well as psychology. The key to such autonomy is a strictly normative conception of truth. Truth consists in normative necessity, in the obligation to follow rules that lead us toward knowledge. This necessity tells us what we ought to think, not what we are compelled to think. Logic thus becomes a discipline of norms, steering clear of both psychological and metaphysical entanglements. Its task is to determine whether thought conforms to its own inner laws, whether it is self-consistent, not whether it mirrors some higher reality. Still, Windelband does not yet abandon his earlier synthesis. His review concerns only formal logic, one branch of epistemology. Logic may stand apart from psychology and metaphysics, but epistemology in the broader sense still seeks to unite them. In the same review, he even warns that logic should not isolate itself completely from epistemology and psychology, since only by referring to them can it demonstrate its relevance to actual knowledge. This position is reaffirmed a year later, in his 1875 article “Knowledge and the Folk-Psychological Approach,” published in the Zeitschrift für Völkerpsychologie und Sprachwissenschaft, the same journal where Cohen had made his debut. There Windelband again endorses a broadly synthetic approach. He insists that while the laws of logic and ethics appear eternal and unchanging, they are still products of human culture. We become aware of them only through education, language, and historical development. To imagine them as existing in isolation from social life is an illusion. He even argues that the forms of logic have meaning only through reference to psychological activity. Norms are not free-floating entities; they direct and regulate human thinking. Without thinking, they would be empty. The laws of logic presuppose communication and discourse—persuasion, correction, and criticism. Even the law of non-contradiction makes sense only within the practice of asserting and denying, which are themselves acts of speech. The principle of sufficient reason, likewise, depends on the activity of giving and demanding reasons, an interpersonal process aimed at persuasion. This emphasis on psychology and culture led some readers to call Windelband a relativist or pragmatist. Yet he ends the article by affirming the universality and necessity of logical laws. Explaining their origin does not undermine their validity. They remain absolute norms even if their recognition has a history. In these years, then, he is still firmly committed to a synthetic conception of epistemology, combining logical, psychological, and metaphysical dimensions. But centrifugal forces are beginning to pull them apart. In his 1876 inaugural lecture at Zurich, “On the Present State of Psychology,” Windelband again praises the alliance between philosophy and the empirical sciences, especially psychology. But he also insists that cooperation requires clear boundaries. The old days of speculative philosophy are over, yet philosophy must not lose itself in empirical work. If the disciplines are to collaborate, each must know its proper task. This insistence on boundaries reflects the broader academic climate. By the 1870s, psychology was rapidly becoming an independent science, and philosophers risked losing their chairs to psychologists. Windelband’s strategy is subtle. Instead of defending philosophy’s independence directly, he calls for the independence of psychology. If psychology becomes a self-sufficient science, it will no longer compete with philosophy. Psychology, he argues, can make progress only when it frees itself from metaphysics. Cooperation with philosophy is impossible while metaphysical disputes remain unresolved, and metaphysics has too often relied on abstract entities like “the soul” or “life-force” that hinder empirical research. Philosophy should therefore let psychology pursue its own empirical path. What remains for philosophy itself is the justification of scientific method and the grounding of the fundamental forms of explanation—in short, logic. This move effectively breaks apart his earlier synthesis. Philosophy becomes logic, psychology becomes an independent science, and metaphysics is left behind. The shift is not yet final, but the pieces are starting to separate. The break deepens the following year, in his 1877 article on Kant’s doctrine of the thing-in-itself. Windelband argues that Kant held three inconsistent views of the thing-in-itself: that it is unthinkable, that it may be assumed though unknowable, and that it must be assumed to explain appearances. Kant’s genius, he claims, lies in the first of these: the thing-in-itself is not merely unknowable but meaningless. Objectivity derives not from correspondence with an external reality but from the lawful synthesis of sensations within experience. The true spirit of critical idealism abolishes the thing-in-itself entirely. This interpretation has far-reaching consequences. If Kant’s philosophy needs no thing-in-itself, then epistemology has no need of metaphysics. Knowledge must be explained wholly within itself. And since the causal relation between representations and objects was the basis of Kant’s psychological questions, dropping the thing-in-itself also removes psychology from the picture. The focus shifts from causes to justification, from quid facti to quid juris. By 1877, then, Windelband has arrived at an almost fully normative conception of philosophy. Two pressures brought him there: the institutional division of labour, which separated philosophy from psychology and metaphysics, and his reading of Kant as a pure critical idealist. From now on, philosophy would concern itself not with how knowledge arises, but with what entitles us to call it knowledge at all. A later scholar, Klaus Christian Köhnke, gave this development a political twist, arguing that Windelband’s move to normativity was prompted not only by intellectual reasons but by the political turmoil of 1878, when two assassination attempts on Kaiser Wilhelm I provoked panic among conservatives and led to Bismarck’s anti-socialist laws. According to this reading, Windelband’s insistence on universal values was a reactionary defence of elite culture against the rising working class and democracy. There is some truth in this, though it oversimplifies. Windelband was indeed politically conservative and wary of mass democracy, but his conception of universal norms was not meant to exclude people by birth or class. It was meant to affirm the authority of reason, which, in principle, any educated person could share. His lectures on Hölderlin and on Socrates from the late 1870s reveal this ambivalence. He attacks the fragmentation of modern society and the shallowness of popular culture, yet he also insists on education as the path to autonomy and on philosophy as the force that can unify the sciences into a coherent worldview. If he mistrusted democracy, it was the uneducated variety that he feared, not the ideal of public reason itself. His Socrates is no enemy of Enlightenment, but of its superficial forms. True reason, Windelband says, becomes authority only for those who have not yet learned to think freely. When reflection is complete, authority and autonomy coincide. By the end of the decade, his conception of philosophy is clear. The early syncretism has broken down under the pressures of academic specialisation and critical reflection. Philosophy’s task is now the justification of knowledge, not its psychological explanation or metaphysical grounding. Logic, understood as the science of norms, becomes the model for all philosophy. Psychology and metaphysics continue their own paths, but philosophy stands apart, guarding the idea of validity itself. Rehmke begins from a deceptively simple premise: what exists must be composed of simple entities. From this he draws striking consequences. These simples, he says, can be thought of as atoms, much as modern physics does, yet they are not physical atoms in space. They are non-spatial and non-material. The spatial and physical character of the world comes only from the way these simple beings combine. Matter, therefore, is not a basic substance at all but an aggregate, a construction from more fundamental elements. To treat matter itself as a thing is to reify an abstraction. This leads him to a radical revision of Kant’s theory of space and time. Kant’s Transcendental Aesthetic, often praised as the best example of critical reasoning, strikes Rehmke as deeply flawed. He cannot accept the idealist claim that space and time are purely subjective forms of intuition, which would vanish if there were no human minds to perceive. Still, he believes that Kant left hints of a more realist interpretation. Kant, after all, never claimed to derive the concrete spatial relations between things directly from the pure intuition of space; he even suggested that these relations depend on dynamic interactions such as attraction and repulsion between bodies. Kant also denied that space is an innate idea preceding perception, instead saying that our idea of space develops through experience of spatial relations. For Rehmke, Kant’s only legitimate conclusion is that our subjective idea of space resembles real space qualitatively but not quantitatively. Yet Kant overreached, he says, by asserting that space and time are only subjective and would disappear with us. Why did Kant do this? Rehmke suspects a theological motive: Kant wanted to preserve human freedom by keeping the noumenal world beyond space and time. That concern for faith distorted his theory. Rehmke reverses the order of dependence. We perceive spatially and temporally, he says, not because our minds impose space and time upon the world, but because the world itself is spatial and temporal, and our senses have adapted to it. Space arises from the relations among things, not as a container in which they sit. If there were no things, there would be no relations, and without relations no space at all. This objective order of relations constitutes what he calls intelligible space—a structure grasped by thought, not by sense. We infer it from the harmony between our perceptual order and the real causal order of things. In this respect his view follows Herbart and Leibniz, though he admits a Kantian element when he recognises that there is also a subjective order of space, the form of intuition that organises our perceptions. The subjective form has an a priori side, not as an innate idea but as a natural tendency of the mind to conceive space as a single infinite expanse. We imagine infinite space though no such infinity exists in nature. Despite his criticism of Kant’s Aesthetic, Rehmke retains much of Kant’s distinction between appearances and things in themselves. He rejects any crude realism that equates what appears with what is, yet he will not accept a dual-world doctrine that separates phenomena from noumena absolutely. Appearances are not entities distinct from things in themselves; they are those very things as they are perceived. When we say “this is red,” we are not merely describing a private experience. The object really is red in relation to beings like us. The relation between appearance and thing parallels that between a composite and its simple parts. The world consists of independent substances whose interactions are combined in perception into unified appearances. This view recalls Leibniz’s claim that appearances are confused representations of the underlying monads, showing again the debt Rehmke owes to Leibniz’s metaphysics. Three principles shape his early philosophy. The first is nominalism: everything real is individual, universals exist only in and for thought. From this follow several consequences. There are no genuine forces in nature, only repeated patterns we describe with general terms. There is no teleology in the classical sense, since ideas or forms have no causal power. And there is no empty, absolute space or time, only the network of relations among things. The second is naturalism: all that exists belongs to nature. Knowing itself has its origins on earth, and there is no separate realm of spirits or intelligibles beyond the natural order. To treat human thought and will as natural processes commits him to granting reality to nature itself. The third is vitalism in a special sense. Everything in nature is alive or psychical, not in the mystical sense of a special life-force, but because the simplest entities must be active, not inert. Matter arises from the activity of these elements, and the difference between the physical and the psychic is a matter of degree, not of kind. At the highest degree of this inner striving lies consciousness. This vitalistic strain, inherited from Leibniz, would later vanish from his thought, but in his youth it animated a heady synthesis of Kant’s transcendental idealism, Leibniz’s monadology, and Herbart’s nominalist naturalism. Rehmke claimed not originality but reconciliation. Yet the reconciliation was fragile. Having denied teleology, he was forced to reintroduce it indirectly through the concept of striving, which implies purposiveness. More seriously, his ontology of independent monads made interaction puzzling: if each is self-contained, how can they affect one another? Leibniz had faced the same problem, solving it with the doctrine of pre-established harmony; Rehmke simply assumed that each monad somehow causes the sensations of others, which only restates the difficulty. His realism therefore lacked secure justification. Recognising these tensions, Rehmke turned to the problem of method. Like many Neo-Kantians, he feared that philosophy was losing relevance in an age of triumphant science. In Über Begriff und Form der Philosophie (1872) he tried to show that philosophy still had a distinct vocation. Two years after his Grundzüge, the tone had changed completely. He had abandoned the syncretism of his earlier period, rejected Herbart’s metaphysics, and reduced Leibniz to a historical influence. Kant, by contrast, now stood at the centre. He begins that little book with a broad sketch of intellectual history. Since antiquity, he says, there have been two main traditions: the scientific one, represented by Aristotle, and the aesthetic-religious one, represented by Plato. The Aristotelian tradition treats knowledge as discursive, achieved by method, definition, and inference. The Platonic tradition treats it as intuitive, achieved by inner vision and inspiration. Modern representatives of the latter include Schelling and Schopenhauer. Rehmke insists that we must choose between them, and he sides decisively with the scientific. To confuse aesthetic or religious feeling with knowledge is, he says, a grave mistake, and to imagine that it stands above science is worse. The criterion of choice is practical: judge them by their fruits. Science has delivered progress and clarity; intuitionist philosophy has produced only vague systems unable to account for the concrete world. The aesthetic-religious path ends in a dualism between lofty vision and empirical fact. By siding with science, Rehmke reveals his positivist leanings, but only up to a point. He admires the rigour of scientific method—its careful induction, its precise definitions, its respect for experience—but he writes not as a positivist but as philosophy’s defender against positivism. His aim is to show that philosophy, too, has a legitimate and distinct domain. The difference, he argues, lies not in method but in subject matter. Science studies the natural world; philosophy studies consciousness of that world. It is the doctrine of consciousness (Bewusstseinslehre). While history deals with particular states of mind, philosophy seeks the general structure of consciousness itself. Truth, goodness, and beauty all exist only for a consciousness; therefore philosophy must study the laws and objects of consciousness scientifically. This raises an immediate difficulty: how does philosophy differ from psychology? Rehmke answers that philosophy studies the content of consciousness—the objects as they appear—whereas psychology studies the processes that produce them. Philosophy analyses products; psychology explains causes. The distinction is partly strategic, protecting philosophy from absorption into the new experimental psychology, but it also anticipates later developments. It prefigures Brentano’s descriptive psychology and Dilthey’s interpretative approach, while marking a sharp break from Herbart’s mechanistic psychology. Yet Rehmke had not thought through the consequences. If philosophy and science share the same method, can we really use scientific method to study the meanings and contents of consciousness? Dilthey would later say no: understanding requires interpretation, not explanation. Rehmke lacked that hermeneutic awareness. He still held that philosophy must proceed scientifically, though he conceded that consciousness cannot be reduced to physical laws. The contents of experience are too heterogeneous for that. His position thus oscillates. He insists that philosophy and science share one method, yet he draws a firm line between the investigation of nature and that of consciousness. Epistemology, ethics, and aesthetics, he admits, require a mode of inquiry different from that of natural science, though he cannot yet say what that mode should be. Still, the little book contains valuable insights. It vigorously defends philosophy against its scientistic critics. The usual complaint, he says, is that philosophy is a priori and deductive, whereas science is inductive and empirical. This view is wrong on both sides. Pure induction is impossible: science always relies on hypothesis, on a priori intuition and deduction to frame and test its questions. A science without pure thought would never reach general laws. Deduction and induction work together, guided by imaginative intuition—the element of insight that allows discovery. Each experiment, he writes approvingly, is a question to nature that already contains an a priori judgement within it. This account of method leads him back to Kant. A year after Cohen’s first book, Rehmke too attacks the psychological reading of Kant and presents him as a logician of knowledge rather than a psychologist. Kant’s aim was not to trace the origin of ideas but to analyse the logical structure of judgements in science, art, and morality. The a priori does not refer to innate forms of mind but to the necessary conditions of valid experience. While Rehmke rejects Kant’s transcendental idealism for its subjectivism, he admires Kant’s critical method. Its great advance, he says, was to investigate the limits and conditions of experience logically, not psychologically. Where Kant went astray was in treating the transcendental subject as if it stood outside nature, instead of within it. Humanity is part of nature, not above it. The a priori forms we find in consciousness might therefore be true not only of thought but of the world itself. Yet this anti-psychological reading of Kant sits awkwardly with Rehmke’s earlier definition of philosophy as the doctrine of consciousness. He seems torn between describing philosophy as a kind of psychology and insisting that it must exclude psychology entirely. His tract ends unexpectedly by turning to history. Since consciousness cannot be separated from its development, he concludes, the history of philosophy is part of philosophy itself. Philosophy should become an historical science, tracing the evolution of spirit through its logical, ethical, and aesthetic forms. Here Hegel, the great philosopher of history, replaces Kant as hero. The enthusiasm was short-lived. Within four years, in 1876, Rehmke published the first volume of Der philosophische Kriticismus and completed his conversion to critical philosophy. The historical and psychological elements now fall away. Philosophy, for him, becomes the critique of metaphysics and the logic of the sciences. The philosophy of Kant, purified of both psychology and idealism, is his model. Critical philosophy, he writes, knows no psychology. Still, his “criticism” is not identical with Kant’s. It means a spirit of inquiry that tests the limits of knowledge while discarding Kant’s dualisms. He sees in Kant two tendencies: one toward the positive sciences, the other toward moral theology. The second must go. Criticism, he now says, is the destruction of the transcendent and the foundation of a humanist philosophy that calls us to build heaven on earth rather than seek it beyond. Because he aligned criticism with humanism and natural science, some have labelled Rehmke a positivist. The label fits only partly. He admired science and distrusted metaphysics, but he also rejected crude empiricism and naïve realism. His aim was to reform philosophy so that it could ground the sciences without being absorbed by them. Rehmke’s mature position is a form of realism, but one carefully balanced between idealism and naïve realism. We know a world that exists independently of us, yet what we know are its appearances, structured by our cognitive activity. The difficulty is to show how those appearances can give genuine knowledge of the things themselves. That challenge drives the long analysis of sensation, space, time, and understanding in the later volumes of his Kriticismus. Sensation, he concludes, is our most basic point of contact with reality. From it all knowledge begins. Riehl makes sensation carry the weight of realism. If we follow the thread of what can be felt, seen and heard, he says, we reach what exists outside us. Touch is exemplary because resistance teaches otherness with a kind of plain force. The world pushes back. The fact that sensory contents arrive and depart without our consent also tells against theories that make the entire scene a hidden product of mind. Diversity across the senses points the same way. If colour, sound and texture hang together, they do so as aspects of one thing. For Riehl, the surest knowledge is closest to concrete sensation, and certainty ebbs as we move into abstraction. This immediacy is not inferential. To perceive is not to argue from inner images to causes. We meet the object itself in space, rather than a picture in the head. Hence his resistance to Helmholtz’s talk of unconscious inference and to physiologists who reify images and retinal happenings. Yet the empiricist emphasis is balanced by a Kantian claim. Sensation is never merely passive reception. It contains an implicit reference to an object, a tacit placing of its source, and so already functions as a primitive judgement of existence. Here belief is both indubitable in practice and indemonstrable in theory. That is Hume’s point recast in a critical vocabulary. Against Müller’s specific energies, Riehl argues that nerves conduct but do not fix the quality of sensation. Evolutionary considerations support him. Senses are adaptations to features of the environment, so it would be strange if they delivered only information about the body rather than about the scene that matters for survival. Still, each sensation bears both an objective and a subjective side. There is the thing sensed, and there is felt tone. The outcome is appearance in the strict sense, that is, how things exist in relation to creatures with our equipment. This is a cautious realism that borders on idealism. We know with confidence that something exists. We do not thereby secure its essence. The quantitative frame alters the picture. In space and time, Riehl pushes further. Purely formal features such as homogeneity, continuity, and the thought of the infinite are a priori, meaning they are supplied by the mind as necessary conditions of experience. But particular relations of coexistence and succession are learned from experience. Three dimensionality is an empirical axiom rather than an a priori truth. We coordinate touch and sight to acquire spatial and temporal representation. On that basis, Riehl treats measurement as discovery rather than construction. The number of times a rod fits a length is fixed by the object, not by our procedure, so size and distance look like properties of things themselves. If the story ended there, we would have a robust scientific realism about the world’s metric structure. It does not end there. In his later volume Riehl confronts the mind body problem as it appears within the life sciences. Biology needs the efficacy of consciousness to make sense of adaptation. Physiology treats consciousness as a by-product of neural events. The standoff is dissolved, he thinks, by critical monism. There is one reality approached by two methods. First person, qualitative concepts pick out the same processes that third person, quantitative concepts describe. Mechanical explanation then ranges over appearances only. It does not reach the thing as it is in itself. This move weakens the earlier realism. If mechanical orders are confined to appearance, then precise spatial and temporal attributions no longer state how things are in themselves. Riehl accepts this loss rather than grant materialism the claim that the spatial temporal world is the last word about reality. He defines materialism as the thesis that appearance and its external ground are congruent. To block that thesis he preserves a gap. What remains is a thin but deliberate realism. Existence is real and independent. Natures are not known. Riehl’s defence of things in themselves is therefore central. He reads Kant as a formal idealist who must presuppose a real source of the matter of experience if he is to avoid Berkeley. To appear is always to be something that appears. He distinguishes the noumenon in the narrow sense, the object of intellectual intuition, which is a problematic idea only, from the thing in itself as ground of appearance, which he takes to be assured. He invokes Kant’s distinction between thinking and knowing to explain why causal concepts can be extended beyond experience without violating the limits of proof. He also reconstructs the argument in phenomenological form. If one analyses representation, one finds a contributed form and a given content. Given content implies a source that is not ourselves. These interpretative manoeuvres oppose both Schopenhauer’s reduction of the empirical to illusion and the Neo Kantian tendency to dissolve the thing in itself into a mere rule or goal. Riehl grants the moral motive behind Kant’s second sense of the noumenal but denies that a hypothetical realm of intelligibles can support ethics. He promises a realist foundation for value but does not supply it. His late work returns to the fate of philosophy. The Freiburg lecture pushes a severe line. Science does the world describing. Classical systematic ambitions and grand world views are obsolete. Philosophy survives as epistemology, a second order inquiry into the logic of the sciences. This rescues autonomy but at a cost. It sidelines the practical vocation that has belonged to philosophy since antiquity. Riehl soon widens his proposal. Alongside the theoretical task he now places a practical one concerned with ethics, politics and aesthetics. That practical side prescribes ends and sketches a plan of life. It sits above the sciences because it answers a different kind of question. Here too, however, the foundations are left unsettled. He oscillates between saying that values are discovered and saying that they are creations of will and feeling. He gestures toward Kantian ideas but doubts that the categorical imperative can yield concrete guidance. The result is a divided conception. Logic of science below, guidance for life above, with no clear bridge between them. Riehl’s project is held together by a simple discipline. Begin from sensation. Distinguish the formal from the material. Treat measurement as disclosure but keep mechanics on the side of appearance. Affirm the thing in itself for the sake of realism, while denying that science exhausts what there is. In doing so he keeps faith with the critical spirit and with the naturalistic temper of his time, yet accepts a modest boundary. What we can justifiably claim to know thins at the point where explanation would become metaphysics. What matters for conduct thickens at the point where knowledge would become advice. The two halves never fully meet, but the line between them is marked with unusual care.