ch the connection is effected). The
categories represent the different kinds of combination, each one of these,
again, being completed in three stages, which are termed the Synthesis of
Apprehension in Intuition, the Synthesis of Reproduction in Imagination,
and the Synthesis of Recognition in Concepts. If I wish to think the time
from one noon to the next, I must (1) grasp (apprehend) the manifold
representations (portions of time) in succession; (2) retain or renew
(reproduce) in thought those which have preceded in passing to those which
follow; (3) be conscious that that which is now thought is the same
with that thought before, or know again (recognize) the reproduced
representation as the one previously experienced. If the mind did not
exercise such synthetic activity the manifold of representation would not
constitute a whole, would lack the unity which consciousness alone can
impart to it. Without this _one_ consciousness, concepts and knowledge of
objects would be wholly impossible. The unity of pure self-consciousness
or of "transcendental apperception" is the postulate of all use of the
understanding. In the flux of internal phenomena there is no constant
or abiding self, but the unchangeable consciousness here demanded is a
precedent condition of all experience, and gives to phenomena a connection
according to laws which determine an object for intuition, _i.e._, the
conception of something in which they are necessarily connected.[1]
Reference to an object is nothing other than the necessary unity of
consciousness. The connective activity of the understanding, and with
it experience, is possible only through "the synthetic unity of pure
apperception," the "I think," which must be able to accompany all my
representations, and through which they first become _mine_.

[Footnote 1: Object is "that which opposes the random or arbitrary
determination of our cognitions," and which causes "them to be determined
in a certain way _a priori_."]

Experience (in the strict sense) is distinguished from perception
(experience in the wide sense) by its objectivity or universal validity. A
judgment of perception (the sun shines upon the stone and the stone becomes
warm) is only subjectively valid; while, on the other hand, a judgment of
experience (the sun warms the stone) aims to be valid not only for me and
my present condition, but always, for me and for everyone else. If the
former is to become the latter, an _a priori_