[1095] Above, pp. 295-6, 311 n. 4.
[1096] There is this difference between the category of existence and the categories of relation, namely, that it would seem to be impossible to distinguish between a determinate and an indeterminate application of it. Either we assert existence or we do not; there is no such third alternative as in the case of the categories of substance and causality. The category of substance, determinately used, signifies material existence in space and time; indeterminately applied it is the purely problematic and merely logical notion of something that is always a subject and never a predicate. The determinate category of causality is the conception of events conditioning one another in time; indeterminately employed it signifies only the quite indefinite notion of a ground or condition. Also, Kant’s explicit teaching (A 597 ff. = B 625 ff.) is that the notion of existence stands in an altogether different position from other predicates. It is not an attribute constitutive of the concept of the subject to which it is applied, but is simply the positing of the content of that concept as a whole. Nor, again, is it a relational form for the articulation of content. These would seem to be the reasons why no distinction is possible between a determinate and an indeterminate application of the notion of existence, and why, therefore, Kant, in defending the possible dual employment of it, has difficulty in holding consistently to the doctrines expounded in the Postulates. He is, by his own explicit teaching, interdicted from declaring that the notion of existence is both a category and not a category, or, in other words, that it may vary in meaning according as empirical or noumenal reality is referred to, and that only in the former case is it definite and precise. Yet such a view would, perhaps, better harmonise with certain other lines of thought which first obtain statement in the Dialectic. For though it is in the Dialectic that Kant expounds his grounds for holding that existence and content are separate and independent, it is there also that he first begins to realise the part which the Ideas of Reason are called upon to play in the drawing of the distinction between appearance and reality.
[1097] In the Fortschritte (Werke (Hartenstein), viii. p. 548 ff.) this final step is quite definitely taken. Cf. below, pp. 390-1, 414-17, 426 ff., 558-61. We have, as we shall find, to recognise a second fundamental conflict in Kant’s thinking, additional to that between subjectivism and phenomenalism. He alternates between what may be entitled the sceptical and the Idealist views of the function of Reason and of its relation to the understanding, or otherwise stated, between the regulative and the absolutist view of the nature of thought. But this conflict first gains explicit expression in the Dialectic.
[1098] For Kant’s use of the terms ‘canon’ and ‘dialectic’ cf. above, pp. 72, 77-8, 173-4, and below, p. 425 ff.
[1099] Above, pp. 181-2.
[1100] As we shall have occasion to observe below (p. 336), when Kant defines judgment as “the faculty of subsumption under rules,” he is really defining it in terms of the process of reasoning, and thus violating the principle which he is professedly following in dividing the Transcendental Logic into the Analytic of Concepts, the Analytic of Judgment, and the Dialectic of Reasoning.
[1101] A 132 = B 171.
[1102] Pp. 252-3, 258-9, 287-8.
[1103] The passages that have gone to constitute this chapter are probably quite late in date of writing. This would seem to be proved by the view taken of productive imagination, and also by the fact that in the Reflexionen there is no mention of schematism.
[1104] Cf. above, p. 176 ff.