\ S U B J E C T I V E AND C R I T I C A L
ID E A LIS M
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further application; since “ reason without sense is empty, as sense without reason is blind.” The sup posed real world, the world an sich, independent of experience, although postulated by the reason, remains ;i “ thought-w orld,” noum enal as opposed to pheno menal, inaccessible, unknown. Thus the ideas of the reason, God, freedom, imm ortality, remain mere postu lates or demands, instruments of organisation, so far as the reason is concerned. The attempt to apply them to a “ noum enal” world leads to insoluble contradictions the “ antinomies of the pure reason.” I his limitation upon the application of the forms of knowledge applies equally to the inner world, to the r||. Know ledge stops with the empirical or pheno m en al s e l f ; it does not reach the noumenal ego. The a priori form s are such only in the structure of know ledge, of which they are the logical conditions; they do not justify the assertion of a substantial self, any more than that of a substantial world. I'he process of “ transcendental apperception” — K a n t’s rendering of the synthetic and reflective func tion, called by Leibnitz “ apperception ” — does not escape 1 lie degradation to phenomenalism, due to its operation upon experiential data. The two sides of experience, the known world and the known self, coalesce in the one organised experience. On the right, but inacces sible, is a postulated real w o rld ; on the left, equally inaccessible, is a postulated real self. K now ledge is powerless to reach either the one or the other. In this conclusion as to the nature and limitations oI knowledge, K an t is both a powerful antagonist and a powerful ally of David Hume. His criticism 1—assum ing its validity— refutes the sensational and associalional theory of knowledge, simply by reverting, when