Kant's Refutation of Idealism

Kant's Refutation of Idealism MYRON GOCHNAUER IN THE SECONDEDITIONof the Critique of Pure Reason Kant inserted a refutation of idealism in the examination of the "Postulates of Empirical Thought." This is one of the most condensed sections of the Critique, but because of the nature of its subject it is also one of the most important. It is the most direct attempt to set the Kantian position off from Berkeley and more particularly from Descartes. In spite of the evident importance Kant placed on these passages the argument is marred by subtle shifts of terminology so that the casual reader is likely to misunderstand the position which is being upheld. Indeed, as we shall see, this terminological difficulty is to be found in the very formulation of the thesis to be proved in the section. It is the purpose of this paper to draw out, or perhaps to reconstruct, the main argument of the refutation and in the process clarify exactly what is and what is not being proved. The argument as it will be reconstructed is not found explicitly in the section under consideration, but then it can hardly be expected that what is essentially a one-paragraph argument can adequately spell out all that it involves, particularly when the literary style is a good illustration of all the negative comments which have been leveled against the German metaphysical writings. In the section which Kant labels the "Refutation of Idealism" he proposes to deal with what he calls "material idealism." This is defined as the "theory which declares the existence of objects in space outside us either to be merely doubtful and indemonstrable or to be false and impossible" (B 274). 1 The former is dubbed problematic idealism and the latter dogmatic idealism. The problematic type is best illustrated, according to Kant, by Descartes, and the dogmatic type by Berkeley. There seems to be considerable agreement among commentators that many of the changes in the second edition, including the addition of this refutation, were attempts to correct misunderstandings and misinterpretations of the first edition which resulted in, among other things, Kant being identified with some form of idealism, presumably close to a l]erkelean position.2 If the motive behind this section was a concise and unquestionable refutation of, and hence differentiation from, Berkeley, then it is a failure, for it deals in cursory fashion with the position of Berkeley, merely reaffirming that there is a difference between the Critique's position and the dogmatic idealist, and referring the reader back to the arguments of the "Aesthetic." Kant takes dogmatic idealism to be based primarily on the proposition that the existence of things in space is impossible, and that this impossibility stems from the impossibility of space itself (B 274). This position results, he says, from holding that space and time are properties of things in themselves. If we hold this view then we are 1 All references to the Critique are from the Norman Kemp Smith translation (Macmillan, 1929). 2 See,for example, H. J. Paton, Kant's Metaphysics of Experience (GeorgeAllen and Unwin, 1936),II, 376, and T. D. Weldon,Kant's Critiqueof PureReason (Oxford, 1958),p. 81 and p. 189. [195] 196 HISTORY OF PHILOSOPHY committed to the absurdities that "two infinite things, which are not substances, nor anything actually inhering in substance, must yet have existence, nay, must be the necessary condition of the existence of all things, and moreover must continue to exist, even although all existing things be removed" (B 70-71). This view was discussed in the "Aesthetic" and supposedly refuted there by showing that space and time are not absolute in the sense of being somehow associated with things in themselves, but rather are the forms of sensible intuition. The argument of the "Aesthetic," then, undermines the dogmatic idealist by showing that space is not impossible. It is beyond the scope of this paper to examine this argument, for it would involve a careful examination of the "Aesthetic" as a whole. Without making any judgment on the soundness of the "Aesthetic" we can, however, see that it does not do all that Kant would require of it in establishing the...