The Non-spatiality of Things in Themselves for Kant

The Non-spatiality of Things in Themselves for Kant* HENRY E. ALLISON I. IN THE Transcendental Aesthetic Kant argued from the a priori nature of our representation of space (and time) to its empirical reality and transcendental ideality. By the "empirical reality" of the representation of space Kant meant its "objective validity" with respect to "outer appearances" or objects of human experience. "Transcendental ideality," on the other hand, refers to its lack of objective validity with respect to the same objects considered as they are in themselves. Appearances, in other words, really are in space, but things in themselves are not. As Kant himself expressed this result: Our exposition therefore establishes the reality, that is, the objective validity, of space in respect of whatever can be presented to us outwardly as object, but also at the same time the ideality of space in respect of things when they are considered in themselves through reason, that is, without regard to the constitution of our sensibility. We assert, then, the empirical reality of space, as regards all possible outer experience; and yet at the same time we assert its transcendental ideality--in other words, that it is nothing at all, immediately we withdraw the above condition, namely, its limitation to possible experience, and so look upon it as something that underlies things in themselves. (A28/B44) Kant's whole line of argument in the Transcendental Aesthetic has been subject to innumerable objections. My present concern, however, is only with one particular objection that can be regarded as classical, namely the neglected alternative charge. This objection was explicitly raised by Trendelenburg in the nineteenth century, and it formed the basis of an extended and acrimonious debate with Kuno Fischer, the details of which have been recorded by Vaihinger. 1 Trendelenburg's main point was that Kant's argument does not rule out the possibility of space being subjective and objective at the same time. As he expressed the matter: "Even if we concede the argument that space and time are demonstrated to be subjective conditions which, in us, precede perceptions * This is a revised version of a paper which I initially presented at the Eastern Division Meeting of the American Philosophical Association in Washington, D.C., December, 1974. The bulk of the revisions are due to my efforts to deal with some of the criticisms offered by my commentator, Professor Richard Aquila, and to make use of the results of a recent and important book by Gerold Prauss, Kant und das Problem der Dinge an sich, (Bonn, 1974), which was not available to me at the time that I wrote the initial version of this paper. Although Prauss does not deal with the specific issue of this paper, his results tend to strongly support my analysis. 1 Hans Vaihinger, Commentar zur Kant's Kritik der reinen Vernu/t (Stuttgart, Berlin, Leipzig , 1892), II, 134-151. [313] 314 HISTORY OF PHILOSOPHY and experience, there is still no word of proof to show that they cannot at the same time be objective forms.''2 To be "objective forms" here obviously means to pertain to things in themselves. Trendelenburg's objection is thus that, even if, for the sake of argument, one accepts Kant's claims concerning the apriority and subjectivity of our representation of space, it is still perfectly possible that space itself or spatial relations pertain to things in themselves . The same point has also been put succinctly by Kemp Smith who writes: "Kant recognizes only two alternatives, either space as objective is known a posteriori or being an a priori representation it is subjective in origin. There exists a third alternative, namely that although our representation of space is subjective in origin, space is itself an inherent property of things in themselves.'3 However, although Trendelenburg's formulation decisively influenced all subsequent treatments of this issue, including Kemp Smith's, he was far from the first Kant critic to raise this line of objection. This is because the third alternative, which he and Kemp Smith suggest Kant failed to consider, is no merely logical possibility, but expresses the essence of the Leibnizian position which Kant attacks in the Transcendental A esthetic. We thus...