This attempt succeeds as well as we could desire, and promises to
metaphysics, in its first part—that is, where it is occupied with
conceptions a priori, of which the corresponding objects may be
given in experience—the certain course of science. For by this new
method we are enabled perfectly to explain the possibility of a priori
cognition, and, what is more, to demonstrate satisfactorily the laws
which lie a priori at the foundation of nature, as the sum of the
objects of experience—neither of which was possible according to
the procedure hitherto followed. But from this deduction of the
faculty of a priori cognition in the first part of metaphysics, we
derive a surprising result, and one which, to all appearance,
militates against the great end of metaphysics, as treated in the
second part. For we come to the conclusion that our faculty of
cognition is unable to transcend the limits of possible experience;
and yet this is precisely the most essential object of this science.
The estimate of our rational cognition a priori at which we arrive
is that it has only to do with phenomena, and that things in
themselves, while possessing a real existence, lie beyond its
sphere. Here we are enabled to put the justice of this estimate to the
test. For that which of necessity impels us to transcend the limits of
experience and of all phenomena is the unconditioned, which reason
absolutely requires in things as they are in themselves, in order to
complete the series of conditions. Now, if it appears that when, on
the one hand, we assume that our cognition conforms to its objects
as things in themselves, the unconditioned cannot be thought without
contradiction, and that when, on the other hand, we assume that our
representation of things as they are given to us, does not conform
to these things as they are in themselves, but that these objects,
as phenomena, conform to our mode of representation, the contradiction
disappears: we
and principles which we assume a priori, our only course ill be to view them from two different sides. We must regard one and the same conception, on the one hand, in relation to experience as an object of the senses and of the understanding, on the other hand, in relation to reason, isolated and transcending the limits of experience, as an object of mere thought. Now if we find that, when we regard things from this double point of view, the result is in harmony with the principle of pure reason, but that, when we regard them from a single point of view, reason is involved in self-contradiction, then the experiment will establish the correctness of this distinction.
