Transcendental analytic showed us how the mere logical form of our cognition can contain the origin of pure conceptions à priori, conceptions which represent objects antecedently to all experience, or rather, indicate the synthetical unity which alone renders possible an empirical cognition of objects. The form of judgements—converted into a conception of the synthesis of intuitions—produced the categories which direct the employment of the understanding in experience. This consideration warrants us to expect that the form of syllogisms, when applied to synthetical unity of intuitions, following the rule of the categories, will contain the origin of particular à priori conceptions, which we may call pure conceptions of reason or transcendental ideas, and which will determine the use of the understanding in the totality of experience according to principles. The function of reason in arguments consists in the universality of a cognition according to conceptions, and the syllogism itself is a judgement which is determined à priori in the whole extent of its condition. The proposition: “Caius is mortal,” is one which may be obtained from experience by the aid of the understanding alone; but my wish is to find a conception which contains the condition under which the predicate of this judgement is given—in this case, the conception of man—and after subsuming under this condition, taken in its whole extent (all men are mortal), I determine according to it the cognition of the object thought, and say: “Caius is mortal.” Hence, in the conclusion of a syllogism we restrict a predicate to a certain object, after having thought it in the major in its whole extent under a certain condition. This complete quantity of the extent in relation to such a condition is called universality (universalitas). To this corresponds totality (universitas) of conditions in the synthesis of intuitions. The transcendental conception of reason is therefore nothing else than the conception of the totality of the conditions of a given conditioned. Now as the unconditioned alone renders possible totality of conditions, and, conversely, the totality of conditions is itself always unconditioned; a pure rational conception in general can be defined and explained by means of the conception of the unconditioned, in so far as it contains a basis for the synthesis of the conditioned. To the number of modes of relation which the understanding cogitates by means of the categories, the number of pure rational conceptions will correspond. We must therefore seek for, first, an unconditioned of the categorical synthesis in a subject; secondly, of the hypothetical synthesis of the members of a series; thirdly, of the disjunctive synthesis of parts in a system.