This, then, is a catalogue of all the originally pure conceptions of the synthesis which the understanding contains à priori, and these conceptions alone entitle it to be called a pure understanding; inasmuch as only by them it can render the manifold of intuition conceivable, in other words, think an object of intuition. This division is made systematically from a common principle, namely the faculty of judgement (which is just the same as the power of thought), and has not arisen rhapsodically from a search at haphazard after pure conceptions, respecting the full number of which we never could be certain, inasmuch as we employ induction alone in our search, without considering that in this way we can never understand wherefore precisely these conceptions, and none others, abide in the pure understanding. It was a design worthy of an acute thinker like Aristotle, to search for these fundamental conceptions. Destitute, however, of any guiding principle, he picked them up just as they occurred to him, and at first hunted out ten, which he called categories (predicaments). Afterwards be believed that he had discovered five others, which were added under the name of post predicaments. But his catalogue still remained defective. Besides, there are to be found among them some of the modes of pure sensibility (quando, ubi, situs, also prius, simul), and likewise an empirical conception (motus)—which can by no means belong to this genealogical register of the pure understanding. Moreover, there are deduced conceptions (actio, passio) enumerated among the original conceptions, and, of the latter, some are entirely wanting. With regard to these, it is to be remarked, that the categories, as the true primitive conceptions of the pure understanding, have also their pure deduced conceptions, which, in a complete system of transcendental philosophy, must by no means be passed over; though in a merely critical essay we must be contented with the simple mention of the fact.