Kant’s pervasive dualism stands in stark contrast to the anti-dualist and, more generally, anti-pluralist approach in first philosophy sought by his predecessors in German school philosophy with their reduction of all mental activity to operations of a single force, the force of representation (Vorstellungskraft, vis repraesentativa), believed to unify the many mental faculties and capacities under a common real force from which they allegedly originate as from a single source. On Kant’s contrary account, the invocation of a single, all-encompassing force amounts to but a nominalist maneuver surreptitiously and superficially gathering the manifest plurality of mental forces under a shared designation (“representing,” “representation”; vorstellen, Vorstellung) to which no real particular force along with its actual exercise can be found to correspond.

But Kant’s critical anti-monism seems equally alien to the core concern of his own successors, the German idealists, chiefly among them Fichte, Schelling, and Hegel, who—each in their own and different way—aim at overcoming the perceived shortcomings of Kant’s pioneering but allegedly incomplete efforts at a radically reformed and rehabilitated form of philosophy. In particular, the German idealists regard the pervasive dualism of Kant’s critical philosophy a dogmatic remnant to be overcome by a truly radical, originally unified account of reason, with the latter variously figuring as “the I” (das Ich), “spirit” (der Geist), or “the absolute” (das Absolute).

While Kant was hardly in a position to respond, much less to address in detail, the German-idealist charges against his principled dualism, the critical philosophy is entirely able and well suited to counter the post-Kantian programmatic reduction of duality and plurality to unity and identity. Anyone sufficiently familiar with the letter and the spirit of Kant’s critical philosophy will point out the elusiveness, if not the illusionary nature, of the alleged unitary force or faculty underlying the mind’s many modes. Moreover, such a knowledgeable reader of Kant will cite the various ways in which the three Critiques themselves address the maintenance of unity and identity over and against plurality in general and duality in particular: from the schematism of the pure concepts of the understanding in the first Critique, which introduces transcendental schemata as a priori time determinations mediating between the sensual and the intellectual, through the doctrine of the highest good in the second Critique, which mediates sensuous desires and moral motivations, to the third Critique’s purpose of bridging the gap between nature and freedom by means of the reflective power of judgment.

Among the chief devices deployed by Kant himself to balance the dualism characteristic of the critical philosophy with his equal concern to maintain the overall unity of reason and the thoroughgoing identity of the human mind’s principal structure is the power of the imagination (Einbildungskraft). The power of the imagination is featured prominently in the first Critique, especially in the Transcendental Analytic, and also exercises a significant function in the third Critique, specifically in the Critique of Aesthetic Judgment. In the first Critique, the power of the imagination is pointedly introduced to bridge the gap between sensibility and the understanding in the dual constitution of objectively valid theoretical cognition in general and of synthetic a priori cognition in particular. The power of the imagination thus is charged with serving as a mediating third between otherwise opposed extremes.

To be sure, introducing a missing link risks to invite the infinite regress of having to insert ever further devices connecting the newly established opposed ends—a fallacy dating back to Aristotle’s “third man” argument (tritos anthropos). Therefore, the sought conjunction of sensibility and the understanding cannot be externally added but has to be generated from within the opposed duality that is to be unified and integrated. Accordingly, Kant introduces the power of the imagination as a cognitive force akin to sensibility but open to, and expressive of, the exercise of the understanding. On Kant’s account, the power of the imagination is preordained to reconcile the obvious opposition between sensibility and the understanding by providing a shared sphere for their meet and match.

As an intermediary faculty between sensibility and the understanding, the faculty of the imagination in Kant partakes in both basic capacities of the finite, human mind. In its most elementary function, the power of the imagination involves images (Bilder) as modes of mentation that are both sensory and intellectual: sensory in the presentment of figures in space and time, and intellectual in the determination of spatial-temporal shapes in accordance with concepts. Images in this basic figurative sense are regions of space and stretches of time delineated through conceptual determination.

But Kant’s concern in dealing with the power of the imagination as an imaging faculty is not with particular figures involving particular spatiotemporal arrays determined by particular concepts, such as this plate being round. Kant is not even concerned with general figures involving general spatiotemporal features in accordance with general concepts, such as the visual demonstration of triangles having a sum total of internal angles equaling 180 degrees. Rather, Kant is intent on addressing the absolutely preliminary, “transcendental” issue of the very production of any and all images in the first place or “at all” (überhaupt).² In the first Critique, the faculty of the imagination is introduced as a transcendental function for the very generation of images. Accordingly, the deliverances of the faculty of the imagination under scrutiny are not so much images—not even images of a higher order, such as meta-images or images of images. Rather they are procedures, rules, or techniques for the very production of images.

On Kant’s understanding of the matter, the power of the imagination crucially includes and essentially encompasses the absolutely preliminary, transcendental function of making images—particular as well as general images—possible at all by providing a set of procedural devices that predelineate possible figures and configurations in space and time in accordance with most general conceptual determinations. Kant’s technical term for the generative source function for possible images is “schema,” more specifically “transcendental schema.” While ordinary, nontranscendental schemata serve as prototypes of ordinary images, transcendental schemata function as most general generative rules for images of all kinds and hence for images “at all.” To cite Kant’s own example, the schema of a dog is a generic rendition of all such animals without the specifics that a particular, or any particular kind of dog, might exhibit (Kant 1904: B180; 1911: A141).

By contrast, transcendental schemata as rules for the generation of images of any kind involve an extraordinary power of the imagination that is not just reproductive, as the recollective capacity due to which the mind is able to retain or retrieve past images. Neither does the specifically transcendental function of the power of the imagination remain within the confines of the imagination’s productive power manifest in the fabrication of novel images characteristic of artistic invention (Aristotelian poiesis). Rather than merely reproducing earlier images or producing new ones by de- and recomposing previous ones, transcendental schemata make images possible in the first place, and they do so by providing rules for the possible concretion of space and time in general into stretches of time and regions of space in particular.

When Kant terms a schema in general and a transcendental schema in particular a “product of the faculty of the imagination” (Produkt der Einbildungskraft) (Kant 1904: B179; 1911: A140), also referring to a “transcendental product of the power of the imagination” (Kant 1904: B181; 1911: A142), he employs the word “product” in a specific and even technical sense. Transcendental schemata are products being brought forth by the faculty of the imagination. They are not just shaped out of preexisting material by means of fixed forms into which that material is brought. Instead, transcendental schemata in Kant are brought about in a genuinely procreative process, modeled on an organism’s first generation and subsequent growth on the basis of “germs and dispositions in the human understanding” (Kant 1904: B91; 1911: A66). Kant’s familiarity with the conceptuality of organic production dates from his extensive work in natural history in general and in contemporary theory of generation in particular, as evidenced by a series of essays in physical anthropology from the late 1770s and early 1780s, and would find its methodological and doctrinal culmination in the second part of the Critique of the Power of Judgment, the Critique of the Teleological Power of Judgment.³

In producing transcendental schemata, the nonempirically productive power of the imagination, according to Kant, brings forth further features in what is given a priori by the senses, namely, “the manifold of pure intuition a priori” (das Mannigfaltige der reinen Anschauung a priori) (Kant 1904: B102; 1911: A77). Those features in turn are informed by most general conceptual forms (“categories”) that reside, in germinal guise, in the understanding and are first unfolded when being brought to bear on the sensory manifold. The latter, considered in and of itself, is but a virtual complex (“sum-total,” Inbegriff) (Kant 1904: B220; 1911: A177) of possible regions of space and possible stretches of time, with no determinate space and time being as yet delineated. Moreover, the process of transcendental production—of bringing forth schematic structures in the preempirical, “pure” manifold of space and time—results in proto-structures that reflect both the intuitional formal features of spatiotemporal sensibility and the conceptual formal features of the categorial understanding.

In the systematic architectonic of the first Critique, the intermediary status and the joining job of the power of the imagination, in its original function of producing transcendental schemata, form the center of the “schematism of the pure concepts of the understanding” (Kant 1904: B176; 1911: A137), which itself links the two key parts of the Transcendental Analytic, the Analytic of Concepts, and the Analytic of Principles. More specifically, the section so titled follows the Deduction of the Pure Concepts of the Understanding with its sustained proof that the categories possess, in principle, objective validity with regards to both the experience of objects and the objects of such experience (“appearances,” “phenomena”). The section on the transcendental schematism in turn precedes and in fact prepares the presentation and the proofs of the most general principles (“laws”) governing material nature as the sum-total of objects in space and time. In addition, the Schematism chapter of the first Critique refers back to the initial section of the entire work, the Transcendental Aesthetic, with its exposition and elucidation of space and time as the two pure forms of sensibility that serve to shape all sensible intuition.

The central position of the Schematism chapter in the first half of the first Critique clearly corresponds to the special status and the crucial function of the power of the imagination for bringing together the two sets of principal cognitive conditions distinguished by the first Critique: the forms of sensibility (space and time) and the forms of thinking (the twelve categories). In Kant’s generative imagery, the two are jointed through their joint product or offspring, the transcendental schemata, in their further functions as basic structural features of possible experience and its objects.

Still the imagist specification of the categories to intuition-laden, sensorily realized covering concepts for possible empirical objects (sometimes termed “schematized categories,” a term not to be found in Kant though), introduced by Kant in the first Critique, is marked by a peculiar preference for time over space in the categorial uptake of the forms of intuition. According to Kant, the schemata furnished to the categories by means of the original generative power of the imagination involve time rather than space. More specifically, Kant introduces the transcendental schemata provided by the power of the imagination as “a priori determinations of time according to rules” (Zeitbestimmungen a priori nach Regeln) (Kant 1904: B185; 1911: A145, emphasis in the original). The technical term, “determinations of time according to rules,” is coined by Kant to convey the status of transcendental schemata: they result from categorial determination that is brought to bear on a pure manifold of intuition that, in and of itself, is devoid of any determination—a priori as well as a posteriori determination—but which is amenable to such subsequent determination and which, moreover, is prepared for it in terms of its general disposition to eventually assume the character of containing specifically formed particular intuitions.

Rather than having both space and time, as the twin conditions of intuition, be the target of categorial schematization through the power of the imagination, Kant limits the transcendental schemata to time determinations at the exclusion of a matching set of schematic determinations of space. The exclusive function of time in the schematism of the categories belongs to the larger context of the primacy of time over space in the account of sensibility and its cognitive deliverance, that is, intuition, through...