The quality of sensation is in all cases merely empirical, and cannot be represented à priori (for example, colours, taste, etc.). But the real—that which corresponds to sensation—in opposition to negation = 0, only represents something the conception of which in itself contains a being (ein seyn), and signifies nothing but the synthesis in an empirical consciousness. That is to say, the empirical consciousness in the internal sense can be raised from 0 to every higher degree, so that the very same extensive quantity of intuition, an illuminated surface, for example, excites as great a sensation as an aggregate of many other surfaces less illuminated. We can therefore make complete abstraction of the extensive quantity of a phenomenon, and represent to ourselves in the mere sensation in a certain momentum, a synthesis of homogeneous ascension from 0 up to the given empirical consciousness, All sensations therefore as such are given only à posteriori, but this property thereof, namely, that they have a degree, can be known à priori. It is worthy of remark, that in respect to quantities in general, we can cognize à priori only a single quality, namely, continuity; but in respect to all quality (the real in phenomena), we cannot cognize à priori anything more than the intensive quantity thereof, namely, that they have a degree. All else is left to experience. 3. ANALOGIES OF EXPERIENCE. The principle of these is: Experience is possible only through the representation of a necessary connection of Perceptions. PROOF.