Kant's Intuitionism: A Commentary on the Transcendental Aesthetic (review)

This is the most substantial book on Kant’s Transcendental Aesthetic to appear in a long time. Though the Transcendental Aesthetic takes up only thirty-five pages of the six hundred sixty-five pages of the Critique of Pure Reason, it is most important. Kant’s theory of space and time belongs among his most provocative contributions to philosophy, and it is the centerpiece of his so-called transcendental idealism. As such, it has received a great deal of attention even in recent times, just not many book-length treatments.

The book has three parts. The first deals with Kant’s terminology, and in particular with the distinctions between intuition and understanding, form and matter in intuition, and sensation and matter in intuition. Since Kant was far from clear in drawing these distinctions, Falkenstein’s sophisticated discussion adds considerably to a better understanding of them. Part II discusses Kant’s various Metaphysical and Transcendental Expositions. Falkenstein is for the most part sympathetic to Kant’s goals in the Metaphysical Expositions, believing that they go a long way towards establishing that space and time are intuitive or “prior to all processing” (279) and not the result of any kind of synthesis. He is more guarded in his evaluation of the Transcendental Expositions. Though they seem to establish the same conclusion as the Metaphysical Expositions, and though they even seem to strengthen these conclusions, the Transcendental Expositions start from premises that “many will not be able to grant,” like the claim that Euclidean geometry must be presupposed for “solid and enduring objects” (282). Furthermore, they also rely on results established in the Metaphysical Expositions. Thus, while the conclusions of the Metaphysical Expositions are weaker, they are more trustworthy. Falkenstein believes that “far too much attention” has been given to the subjectivity of the forms of intuition, “and far too little (in fact, none) has been focused on the weaker, but still important conclusion that space and time are orders in which sensations are originally received by us” (283). Falkenstein also calls space and time “presentational orders.” In the third part, he examines central claims, which, according to Kant, follow from his arguments, namely, (i) the subjectivity thesis, (ii) the non-spatiotemporality thesis, and (iii) the unknowability thesis. (i) is the claim that space and time “do and must qualify all the objects of our sensory experience” (288); (ii) is the claim that space and time are “absolutely nothing” apart from intuition, and that things in themselves are neither spatial nor temporal; and (iii) is the claim that things in themselves are unknowable. Falkenstein argues that (i) is largely uncontroversial. It is a basic conclusion that follows from his arguments. While (ii) is controversial and might present great difficulties for Kant, it can be rescued, if it is understood simply as the “analytic claim that any order of things in themselves could not be a presentational order” (356). In this sense it is innocuous and follows from Kant’s arguments. The unknowability thesis (iii) seems to conflict both with the non-spatiotemporality thesis in the strong sense and with a number of things which Kant says about affection and the receptive constitution of the subject in intuition. However, it can also be rescued. If we understand (ii) in a mitigated sense, and if we dismiss Kant’s claims about affection and receptive constitution as vacuous, it also presents no fundamental problems. And Falkenstein argues that we should do just that. The claims about affinity and our receptive constitution do not do any work. They “translate Kant’s Critical Idealism into a naive realist paradigm” and are thus “needlessly confusing” (357).

Falkenstein’s book offers a carefully argued and sophisticated account of the Aesthetic. No one concerned with this aspect of Kant’s theoretical philosophy (or indeed any other aspect of it) can afford to ignore it. The book should become an indispensable part of graduate seminars on Kant’s first...