³ The possibility of an experience in general is the possibility of empirical cognitions as synthetic judgements. Thus it cannot be derived analytically from the mere comparison of perceptions (as is commonly believed) since the combination of two different perceptions in the concept of an object (for its cognition) is a synthesis, one which makes empirical cognition, i.e. experience, possible only in accordance with principles of the synthetic unity of appearances, i.e. in accordance with principles which permit the latter to be brought under the categories. Now these empirical cognitions, in accordance with what they necessarily have in common (namely those transcendental laws of nature), constitute an analytic unity of all experience, but not that synthetic unity of experience as a system which binds together under a principle the empirical laws even in regard to their differences (and where their multiplicity may be endless). What the category is with respect to every particular experience, that is what the purposiveness or fitness of nature is to our power of judgement (even with regard to its particular laws), and that is why nature is represented as not merely mechanical, but also as technical, a concept that certainly does not determine synthetic unity objectively, but still subjectively furnishes principles which serve to guide our enquiries into nature.