We naturally feel a preliminary difficulty with respect to the existence of this second part of the _Analytic_ at all. It seems clear that if the first part is successful, the second must be unnecessary. For if Kant is in a position to lay down that the categories must apply to objects, no special conditions of their application need be subsequently determined. If, for instance, it can be laid down that the category of quantity must apply to objects, it is implied either that there are no special conditions of its application, or that they have already been discovered and shown to exist. Again, to assert the applicability of the categories is really to assert the existence of principles, and in fact of just those principles which it is the aim of the _System of Principles_ to prove. Thus to assert the applicability of the categories of quantity and of cause and effect is to assert respectively the principles that all objects of perception are extensive quantities, and that all changes take place according to the law of cause and effect. The _Deduction of the Categories_ therefore, if successful, must have already proved the principles now to be vindicated; and it is a matter for legitimate surprise that we find Kant in the _System of Principles_ giving proofs of these principles which make no appeal to the _Deduction of the Categories_.[2] On the other hand, for the existence of the account of the schematism of the categories Kant has a better show of reason. For the conceptions derived in the _Metaphysical Deduction_ from the nature of formal judgement are in themselves too abstract to be the conceptions which are to be shown applicable to the sensible world, since all the latter involve the thought of time. Thus, the conception of cause and effect derived from the nature of the hypothetical judgement includes no thought of time, while the conception of which he wishes to show the validity is that of necessary succession in time. Hence the conceptions discovered by analysis of formal judgement have in some way to be rendered more concrete in respect of time. The account of the schematism, therefore, is an attempt to get out of the false position reached by appealing to Formal Logic for the list of categories. Nevertheless, the mention of a sensuous condition under which alone the categories can be employed[3] should have suggested to Kant that the transcendental deduction was defective, and, in fact, in the second version of the transcendental deduction two paragraphs[4] are inserted which take account of this sensuous condition. [2] The cause of Kant's procedure is, of course, to be found in the unreal way in which he isolates conception from judgement. [3] B. 175, M. 106. [4] B. §§ 24 and 26, M. §§ 20 and 22.