Again, the third paragraph assumes the possibility of self-consciousness as the starting-point for argument. The thought[77] seems to be this: 'For a self to be aware of its own identity, there must be a manifold in relation to which it can apprehend itself as one and the same throughout. An understanding which was perceptive, i. e. which originated objects by its own act of thinking, would necessarily by its own thinking originate a manifold in relation to which it could be aware of its own identity in thinking, and therefore its self-consciousness would need no synthesis. But our understanding, which is not perceptive, requires a manifold to be given to it, in relation to which it can be aware of its own identity by means of a synthesis of the manifold.' If this be the thought, it is clearly presupposed that _any_ understanding must be capable of being conscious of its own identity.[78]
[77] Cf. B. 138 fin.-139 init., M. 85 fin.
[78] B. 139 init., M. 85 fin. also assumes that it is impossible for a mind to be a unity without being able to be conscious of its unity.
Further, it is easy to see how Kant came to take for granted the possibility of self-consciousness, in the sense of the consciousness of ourselves as the identical subject of all our representations. He approaches self-consciousness with the presupposition derived from his analysis of knowledge that our apprehension of a manifold does not consist in separate apprehensions of its elements, but is one apprehension or consciousness of the elements as related.[79] He thinks of this as a general presupposition of all apprehension of a manifold, and, of course, to discover this presupposition is to be self-conscious. To recognize the oneness of our apprehension is to be conscious of our own identity.[80]
[79] It is in consequence of this that the statement that 'a manifold of representations belongs to me' means, with the probable exception of § 1, not, 'I am aware of A, I am aware of B, I am aware of C,' but, 'I am aware, in one act of awareness, of A B C as related' (= ABC are 'connected in' or 'belong to' one consciousness). Cf. §§ 4, 8 ('in one consciousness'), 9, 10 ('in one consciousness'), and A. 116, Mah. 208 ('These representations only represent anything in me by belonging with all the rest to one consciousness [accepting Erdmann's emendation _mit allen anderen_], in which at any rate they can be connected').