Author: Laura Reagan

First, as concerns the sources of metaphysical cognition, its very concept implies that they cannot be empirical. Its principles (including not only its basic propositions but also its basic concepts) must never be derived from experience. It must not be physical but metaphysical knowledge, i.e., knowledge lying beyond experience. It can therefore have for its basis neither external experience, which is the source of physics proper, nor internal, which is the basis of empirical psychology. It is therefore a priori cognition, coming from pure understanding and pure reason. p.11

From the Norman Kemp-Smith Transcendental Deduction (A) p. 143 We entitle the synthesis of the manifold in imagination transcendental, if without distinction of intuitions it is directed exclusively to the a priori combination of the manifold; and the unity of this synthesis is called tanscendental, if it is represented as a priori necessary in relation to the original unity of apperception. Since this unity of apperception underlies the possibility of all knowledge, the transcental unity of the synthesis of imagination is the pure form of all possible knowledge; and by means of it all objects of possible experience must be represented a priori. The unity of apperception in relation to the synthesis of imagination is the understanding; and this same unity, with reference to the transcendental synthesis of the imagination, the pure understanding.