BEISER'S IDEALISM (6): Kant 1750-1780

Since the historical approach promises the best chance of solving some of the most difficult interpretative disputes, Beiser turns first to Kant’s lifelong struggle with idealism. He traces this struggle from Kant’s earliest writings in the 1750s through to the Opus postumum, the final work of Kant’s life. Each stage shows Kant wrestling with variants of idealism, testing different distinctions and revising his own views in response to both critics and to his own developing sense of the limits of reason. What emerges from this long story is not a simple switch from subjectivism to objectivism or the reverse, but something more layered. Kant’s transcendental idealism is neither a purely subjective doctrine in which everything begins from the inner life of consciousness, nor a purely objective doctrine in which a rational structure transcends the subject. It is a synthesis that takes elements from both sides, while resisting the reductive tendencies of each. 

This synthesis is at once subtle and precarious, and that is why it has generated such heated debate. The task of scholarship, as Beiser sees it, is to specify exactly which parts of the doctrine lean toward the subjectivist model and which lean toward the objectivist one, and how these leanings can coexist in a single system.

Kant’s idealism is objectivist in so far as the necessary structures of experience are not simply ideas in a mind, but the conditions for having ideas at all. These structures are the conditions of both subjectivity and objectivity, since they determine what counts as an inner state and what counts as an object in the external world. In this sense the forms of intuition and the categories are not psychological features of an individual but the a priori architecture without which there could be no experience of any sort. At the same time, Kant’s idealism is subjectivist in so far as appearances are always connected to a transcendental subject which synthesises and orders them, and this subject cannot be erased or replaced by an impersonal function. Kant gives it self awareness and spontaneity, which means that it cannot be reduced to a logical constant. These two sets of commitments do not cancel each other, but they do create tensions that scholars need to understand rather than ignore.

Beiser also notes that Kant occupies an ambivalent position with respect to the older way of ideas, the tradition that begins with Descartes and continues through Locke, Berkeley and Hume. On the one hand Kant denies some of the central assumptions of this tradition, in particular the claims that ideas are given in an immediate and self evident way and that they resemble their objects. On the other hand he sometimes adopts the view that the immediate objects of awareness are representations. For Kant, just as for Berkeley, an idea resembles nothing but an idea. Yet Kant changes the meaning of the principle by applying it to outer as well as inner experience, so that even the perception of objects in space counts as immediate awareness of one’s own representations. By extending it in this way he neutralises the usual sceptical inference. There is no privileged access to the inner, since the inner is known under the same conditions as the outer. Both are known only as appearances and not as things in themselves.

This leads Beiser to another central point: Kant’s transcendental idealism is irreducibly ambiguous. The meaning of the term appearance shifts depending on what problem Kant is addressing. Sometimes an appearance is an aspect of a thing in itself, an extrinsic property that results from the way things affect our sensibility. Sometimes an appearance is nothing more than a representation in the subject. This dual use is not the result of careless language but of Kant’s complex polemical situation. When arguing against transcendental realism, which mistakenly treats appearances as things in themselves, Kant emphasises the representational side. When distinguishing his doctrine from Berkeley’s metaphysical idealism, which dissolves the world into ideas, he emphasises the aspect side. The ambiguity becomes a feature rather than a flaw when viewed from the transcendental standpoint, where appearances can legitimately be taken as both representations and properties of things in themselves. It is only if one tries to impose a single meaning across all contexts that the doctrine appears incoherent. This contextual sensitivity also explains why the debate between the two worlds reading and the two aspects reading cannot be resolved by direct appeal to the text, since Kant’s usage supports both. 

For Beiser, the dispute is sterile because it assumes that one meaning must be primary. Kant’s own practice shows otherwise. The doctrine has both psychological and epistemological dimensions, and the psychological dimension cannot be ignored without undermining the way Kant responds to sceptical problems. He links questions of what we know to questions about the structures that make knowledge possible. Any interpretation that tries to reduce transcendental idealism to a purely logical or structural thesis misses half of what Kant is doing. 

Beiser then turns to the question of Kant’s opponents. Kant’s primary targets were Descartes and Leibniz rather than Berkeley or Hume. He did not think of Hume as an idealist at all, and he interpreted Berkeley’s idealism in largely Leibnizian or Platonic terms. In fact he saw Leibniz as the most important representative of dogmatic idealism and criticised him throughout his career. Many features of Kant’s transcendental idealism, such as the distinction between sensibility and understanding, the empirical reality of space and time, and the restriction of knowledge to appearances, were forged in response to Leibniz’s rationalism. The foundations of Kant’s transcendental idealism were already present in the 1770 Inaugural Dissertation and remain through to the Opus postumum. The later work does not mark a fundamental break. It expands the earlier doctrine by incorporating new ideas about dynamics, but it retains the thing in itself and rejects the extremes of both Fichte’s subjective idealism and Schelling’s absolute idealism. Beiser also does a drive by on recent Kant scholarship. He notes a tendency among some scholars to take extreme positions on the relation between transcendental idealism and scepticism, either praising Kant’s response to scepticism while downplaying his idealism or praising his idealism while downplaying his response to scepticism. Beiser rejects both extremes on the grounds that Kant’s transcendental idealism and his refutation of scepticism are inseparable. Kant saw transcendental idealism as the only possible defence of empirical realism, and only empirical realism can block scepticism. To detach these elements is to misunderstand the very structure of Kant’s project. Another scholarly dispute concerns whether Kant’s transcendental deduction is a reply to scepticism. A modest reading denies that it is. Beiser agrees that Kant is not a foundationalist in the Cartesian sense and that he does not attempt to prove the existence of the external world in the strong sense. But he argues that Kant was concerned with scepticism, since the refutation of idealism in the second edition aims to establish the empirical reality of outer objects against Cartesian doubt. Kant believed that transcendental idealism makes this possible, even though the proof is modest and does not claim to show the reality of things in themselves.

A further controversy concerns the extent of Kant’s subjectivism. Some scholars claim that Kant’s idealism is essentially subjective and barely distinguishable from Berkeley’s. Others claim that it is radically opposed to Berkeley and contains no significant subjectivist element. Beiser argues that both sides overlook the way Kant combines subjectivist and objectivist strands. Those who defend a purely anti subjectivist Kant often ignore the objectivist interpretation developed by Schelling, Hegel and the Marburg school, and in doing so unintentionally adopt assumptions from the very subjectivist reading they reject. They frequently fail to address basic questions, such as the status of the categories or the indispensability of the transcendental subject. The common assumption motivating these debates is that recognising both sides of Kant’s doctrine reveals its incoherence. Beiser argues instead that the synthesis is coherent, though complex. What is incoherent are the attempts to force the doctrine into one exclusive model.

He outlines his alternative: Kant always sought a middle path between subjective and objective idealism. The synthesis he produced is not a patchwork of inconsistent stages but a coherent attempt to unite the strengths of both without succumbing to the weaknesses of either. From this broad sketch Beiser shifts to Kant’s early struggle with idealism, long before the Critique of Pure Reason. People often assume that Kant only became concerned with idealism in the 1780s after critics accused him of being an idealist. But Kant had been wrestling with idealist doctrines since the 1750s. He wrote refutations of idealism in the Nova dilucidatio of 1755 and the Inaugural Dissertation of 1770. His lectures throughout the 1760s and 1770s discuss idealism frequently. In the 1766 Dreams of a Spirit Seer he explores the motives behind idealist metaphysics. His aim in these early decades was to distance his views from what he called the cancer of metaphysics, a disease he associated with idealism in its various forms. Kant viewed idealism and materialism as the two dangerous extremes of metaphysics. By the 1760s German philosophers frequently attacked idealism in their writings and lectures. Berkeley and Hume were already well known. Many thinkers followed the Scottish common sense philosophers, who claimed that Hume’s scepticism exposed the destructive potential of the way of ideas. For Kant, idealism came in several varieties. There was the dogmatic idealism of Plato and Leibniz, who believed that the senses gave only confused appearances and that true knowledge lay in rational insight. There was also the sceptical idealism of Descartes, who doubted the reality of the external world because the inferences behind it might be uncertain. Finally there was the egoism of more radical metaphysical systems that threatened to collapse the world into a single self.

Kant distinguishes these positions carefully in his lectures. Idealism holds that only the immaterial exists or at least only the immaterial is known. Egoism holds that only the self exists or at least only the self is known. Both can take problematic or dogmatic forms. Problematic versions doubt the existence of the world. Dogmatic versions deny it. Kant believed problematic idealism had some value, since it forces us to examine the limits of sense knowledge. But dogmatic idealism, which denies the reality of sense experience, is dangerous for moral and religious reasons and must be rejected. The most important form for Kant, especially in his early years, was the dogmatic idealism of Leibniz and the Platonic tradition. This is unsurprising given Kant’s early education in the Leibnizian school and his later struggle to free himself from its influence. The later Kant even defined all idealism in Platonic terms, describing it as the doctrine that reduces all sensible knowledge to illusion and reserves truth for the ideas of reason alone. For Kant, this is the essence of dogmatic idealism, and it explains why he repeatedly aimed his criticisms at Leibniz.

Several elements in Kant’s early development come directly from his reaction to Leibniz. His first theory of mental physical interaction, which he used to oppose solipsistic consequences of Leibniz’s monadology, later contributed to the refutation of idealism in the first Critique. His doctrine of the parallelism of inner and outer sense, which claims that both provide immediate knowledge of things, grows out of his response to Cartesian problematic idealism. His effort to create a critical idealism that recognises the limits of human cognition stems from his encounter with Swedenborg’s visionary idealism. Perhaps most importantly, his distinction between empirical reality and transcendental ideality was developed in direct reaction to Leibniz’s Platonic metaphysics. Kant’s first explicit refutation of idealism appears in the Nova dilucidatio. It arises within a broader metaphysical debate concerning two principles: the principle of succession, which states that no substance can change by itself and that all change results from its connection with other substances, and the principle of coexistence, which states that substances do not interact simply by existing but require a divine act to place them in harmony. These principles were part of Kant’s attempt to solve the mind body problem without falling into the difficulties of occasionalism, pre established harmony or physical influx. Kant extended the principle of succession beyond bodies to all substances, thus rejecting Leibniz’s claim that all change originates within monads. He limited interaction to extrinsic properties, attempting to preserve the distinct inner nature of mind and body while acknowledging their correlation.

The refutation of idealism in the Nova dilucidatio arises from this theory of interaction. Kant argues that the soul undergoes inner changes, that these cannot arise from the soul alone, and therefore must come from something external to it. He then adds a causal theory of perception to show that a representation is true if it arises from its object. This argument may stop a sceptic from denying that representations have external causes, but it does not show that these causes are material. It could be that the cause of a representation is another mind or even God. Kant tries to meet this difficulty by claiming that space results necessarily from interactions among substances, implying that whatever interacts must be spatial. But this answer risks materialism, since it seems to place even the mind in space. Kant replies that only the extrinsic properties of the mind are spatial and that its intrinsic nature as a thinking being remains untouched. Beiser observes that the most likely target of this early refutation is Leibniz rather than Berkeley or Descartes. Leibniz held that all perceptions arise from within the soul and that external causes play no role. This leads to a quasi solipsistic horror position, since monads could have all their perceptions even if no bodies existed. Kant frequently criticised Leibniz in the Nova dilucidatio and later described him as an idealist and even an egoist. For Kant, the pre established harmony collapses into a form of idealism because it denies genuine interaction and makes the external world superfluous.

Although Kant later abandoned the metaphysical framework of the Nova dilucidatio, its central strategy survives in the first Critique. The critical Kant no longer appeals to interaction among things in themselves, but he still argues that the reality of a representation depends on its place within a lawful system of appearances. The mutual attraction and repulsion of substances in the Third Analogy plays a similar role in establishing the objective reality of experience. Beiser then turns to one of Kant’s strangest early works, Dreams of a Spirit Seer. Although this book mentions idealism only in passing, the entire tract functions as a critique of idealist metaphysics. Kant uses Swedenborg’s mystical visions as a case study in how reason becomes deluded when it attempts to grasp a spiritual world beyond experience. He draws a parallel between rationalist metaphysics and mystical metaphysics. The metaphysician attempts to describe the spiritual world through pure reason. The mystic attempts to describe it through special visions. Both claim access to a realm beyond experience and both fall into nonsense when they ignore the limits of human cognition. Kant takes Swedenborg’s vivid stories of spirits appearing in material places as evidence that the Mystic himself cannot conceive spirituality without smuggling in spatial images. This reveals the central illusion behind both mysticism and dogmatic idealism: they try to speak of what cannot be an object of human intuition. The moral of the Dreams is that metaphysics must become a science of limits. It should not attempt to establish the existence of spiritual substances, since such claims transcend the conditions of experience. Instead metaphysics should clarify what human reason can and cannot know. Kant also insists that the practical motive behind religious belief must not be confused with theoretical insight. Belief in immortality has a moral basis rather than a theoretical one. A critical idealism must therefore avoid speculation about substances beyond experience and instead recognise the empirical reality of sense knowledge.

From this point Beiser moves to the 1770 Inaugural Dissertation, where Kant again distinguishes his doctrine from idealism. He criticises Plato and the Eleatic tradition for disparaging the senses and claiming that reason alone grasps reality. Although the Dissertation retains much of the structure of metaphysics inherited from the rationalists, Kant already argues that sense knowledge is a legitimate form of cognition with its own proper domain. He rejects the Platonic notion of intellectual intuition, insisting that human knowledge is discursive and must receive its objects through sensibility. He also argues that mathematics applies only to appearances because its principles depend on the forms of space and time, which govern the sensible world. Against the dogmatic idealist he insists that appearances give genuine knowledge, not confusion or illusion. This defence of sense knowledge deepens Kant’s project and anticipates the first Critique. He argues that appearances are effects of objects on the mind and that empirical judgments can be true even if they refer only to phenomena. He claims that space and time are forms of intuition that provide order to sensations and allow us to make objective judgments. This enables him to show how the axioms of geometry are necessarily true of the objects of experience. The empirically real yet transcendentally ideal status of space and time is already implicit in this early work, showing that the seeds of transcendental idealism were present before the silent decade.

Beiser highlights an objection raised soon after the Dissertation. Mendelssohn and Lambert worried that if time is ideal, then the changes we experience would also be ideal and therefore unreal. Kant replied that changes are real for appearances even if they are not features of things in themselves. This led him to stress the parity of inner and outer sense, an argument that plays an important role in the refutation of idealism. Both inner and outer experience present immediate representations, so there is no asymmetry between the certainty of inner awareness and the insecurity of outer perception. That asymmetry had been a cornerstone of Cartesian idealism. Kant counters it by insisting that both inner and outer experience are subject to the same conditions of representation. 

Beiser then examines Kant’s ambivalent scepticism in the 1760s and 1770s. In some lectures Kant admits that idealism and egoism cannot be refuted on theoretical grounds. He even defends Berkeley against common objections, suggesting that Berkeley cannot be disproved logically. But he rejects both doctrines on moral grounds, since they undermine the possibility of religion and natural theology. This sceptical attitude reflects Kant’s decreasing confidence in reason during those decades. He becomes increasingly aware that reason cannot prove the existence of anything without empirical evidence and that real causes must be determined by experience rather than by analysis. This raises an apparent problem. If Kant believed reason cannot prove existence, how could he later return to a refutation of idealism. Beiser shows that the tension dissolves once we see that the later refutations do not attempt to prove the existence of things in themselves. Instead they aim to show that certain forms of experience presuppose others. The refutation of idealism shows that inner experience depends on outer experience, not that the external world exists independently of all consciousness. Those who read the refutation as proving the existence of things in themselves misinterpret its critical character.

Finally Beiser examines Kant’s relation to Hume. Although Hume is often described as a sceptical idealist, Kant never uses this term for him. Kant always reserves that label for Descartes. The reason is that Hume’s scepticism targets the principle of causality itself, not the inference from perceptions to external objects. Kant sees Hume as a transcendental realist, someone who naively treats appearances as things in themselves. This reading may seem odd, but it fits with Kant’s view in the second Critique that Hume assumes a realist standard of truth and then doubts that we can meet it. Kant also read Hume narrowly, focusing on his doubts about causality rather than on his broader scepticism about the senses. This narrow reading fits with Kant’s aim in the transcendental deduction, which is to show that causal relations are conditions of experience. In this way Beiser shows that Kant’s early philosophical development is inseparable from his constant confrontation with idealism in all its forms. The arc from the 1750s to the 1780s reveals a thinker slowly constructing the framework that will allow him to keep the strengths of rationalism while discarding its illusions, to defend the validity of sense knowledge without falling into naïve realism, and to respect the limits of reason without surrendering to scepticism. This long and complicated struggle is what finally yields the critical idealism that becomes the foundation for later debates.