Schopenhauer's Criticism of Kant's Schemata - Kant's Use of Symmetrical Analogy

Kant's Use of Symmetrical Analogy

Schopenhauer's criticism of Kant's schemata was done, according to him, to help solve the mystery of Kant's way of philosophizing. He tried to show that "… after the happy discovery of the two forms of intuition or perception a priori (space and time), Kant attempts, under the guidance of analogy, to demonstrate for every determination of our empirical knowledge an analogue a priori, and this finally extends in the schemata even to a mere psychological fact. Here the apparent depth of thought and the difficulty of the discussion merely serve to conceal from the reader the fact that its content remains an entirely undemonstrable and merely arbitrary assumption."

…here more than anywhere else do the intentional nature of Kant's method of procedure and the resolve, arrived at beforehand, to find what would correspond to the analogy, and what might assist the architectonic symmetry, clearly come to light. … By assuming schemata of the pure (void of content) concepts a priori of the understanding (categories) analogous to the empirical schemata (or representatives of our actual concepts through the imagination), he overlooks the fact that the purpose of such schemata is here entirely wanting. The purpose of the schemata in the case of empirical (actual) thinking is related solely to the material content of such concepts. Since these concepts come from empirical perception, we assist ourselves and see where we are, in the case of abstract thinking, by casting now and then a fleeting, retrospective glance at perception from which the concepts are taken, to assure ourselves our thinking still has real content. This, however, necessarily presupposes the concepts which occupy us spring from perception…. With a priori concepts, which have no content at all, obviously this is of necessity omitted because these have not sprung from perception, but come to it from within, to first receive content from it.

— The World as Will and Representation, Volume I, Appendix, p. 450

Empirical concepts are ultimately based on empirical perceptions. Kant, however, tried to claim that, analogously, pure concepts (Categories) also have a basis. This pure basis is supposed to be a kind of pure perception, which he called a schema. But such an empiricist analogy contradicts his previous rationalist assertion that pure concepts (Categories) simply exist in the human mind without having been derived from perceptions. Therefore they are not based on pure, schematic perceptions.