it necessary to break off in his investigation and refer to the Strassburger Abhandlungen and also to the later volumes of his work.
According to pages 69-79 the Æsthetic rests upon six unproved premises with relation to the distinction between form and matter. Pages 89-101 prove (especially against Cohen and Riehl) that—at least in the Æsthetic—'the A priori' is essentially identical with 'the innate.' Two essays are devoted to the Fischer-Trendelenburg controversy (pp. 134-151, 290-326). From a thorough, unprejudiced investigation of the facts, Vaihinger reaches the conclusion—which can scarcely be disputed—that though Trendelenburg was guilty of some logico-formal inaccuracies, and also of some errors in regard to subordinate questions, yet on all important points he was essentially right. This is especially true of the claim that Kant has left a gap in the proof given in the Æsthetic for the exclusively subjective character of space and time, and that he overlooked one possibility with regard to their nature. Or—as Vaihinger here improves on Trendelenburg—that at least no serious refutation of this view has been given. Vaihinger goes still further, and claims that Kant overlooked not one but three possibilities.
The essay which deals with the historical genesis of Kant's doctrine of space and time (pp. 422-436) appears to me the least satisfactory part of the work. Vaihinger assumes with B. Erdmann that the antinomies have been the real motive which led to Kant's change of position between 1768 and 1770. But in addition Kant is said (p. 414) to have been also stimulated "in the formation of his own theory" by the study of the celebrated controversy between Clarke and Leibniz concerning space and time. According to p. 133 this study appears to have become of great importance for Kant's development; we are also informed (pp. 518-533) that it was through this that he was led to the "paradoxes of symmetrical objects" [referred to in Prolegomena, § 13]. This suggestion of Vaihinger's is worthy of our thanks and attention. Nevertheless, the question, as he himself grants (p. 414), demands a more exact investigation. Until this has been completed, one can say nothing for or against Vaihinger's assertions. They remain mere assertions for which nothing has yet been brought forward which could by any means be regarded as sufficient proof. All such problems of the historical development of Kant's views can, I think, only be solved in one way; through bringing to light the yet unknown treasures in Reflexionen Kant's (edited by B. Erdmann). If Vaihinger's essay is to be of much value, it must make that its starting point. As
