that an a priori intuition (which is not empirical) lies at the root
of all our conceptions of space. Thus, moreover, the principles of
geometry--for example, that "in a triangle, two sides together are
greater than the third," are never deduced from general conceptions
of line and triangle, but from intuition, and this a priori, with
apodeictic certainty.

4. Space is represented as an infinite given quantity. Now every
conception must indeed be considered as a representation which is
contained in an infinite multitude of different possible
representations, which, therefore, comprises these under itself; but
no conception, as such, can be so conceived, as if it contained within
itself an infinite multitude of representations. Nevertheless, space
is so conceived of, for all parts of space are equally capable of
being produced to infinity. Consequently, the original
representation of space is an intuition a priori, and not a
conception.



SS 3. Transcendental Exposition of the Conception of Space.

By a transcendental exposition, I mean the explanation of a
conception, as a principle, whence can be discerned the possibility
of other synthetical a priori cognitions. For this purpose, it is
requisite, firstly, that such cognitions do really flow from the given
conception; and, secondly, that the said cognitions are only
possible under the presupposition of a given mode of explaining this
conception.