OF THE TRANSCENDENTAL PROBLEMS OF PURE REASON, IN SO FAR AS THEY
ABSOLUTELY MUST BE CAPABLE OF SOLUTION[1537]
There are sciences the very nature of which requires that every question
which can occur in them must be completely answerable from what can be
presumed to be known. This is true of the science of ethics. When I ask
to what course of action I am committed in moral duty, the question must
be answerable in terms of the considerations which have led to its being
propounded. For there can be no moral obligation in regard to that of
which we cannot have knowledge. We must not plead that the problem is
unanswerable; a solution must be found. Kant proceeds to argue that this
is no less true of transcendental philosophy.
“...it is unique among speculative sciences in that no question
which concerns an object given to pure Reason is insoluble for this
same human Reason, and that no excuse of an unavoidable ignorance,
or of the unfathomable depth of the problem, can release us from
the obligation to answer it thoroughly and completely. That very
concept which enables us to ask the question must also qualify us
to answer it, since, as in the case of right and wrong, the object
is not to be met with outside the concept.”
The third and fourth paragraphs would seem to be later interpolations.
The section, like Section III., must have been written at the time when
Kant still regarded the doctrine of antinomy as covering the entire
field of metaphysics. Transcendental philosophy is identified with
cosmology, as dealt with in the antinomies. But in the third paragraph
the former is taken as a wider term. Also, in the first two paragraphs
the problems of pure Reason are regarded as soluble because their
objects are not to be met with outside the concepts of them; whereas in
the third paragraph they are viewed as soluble because their object is
given empirically. Again, in the second paragraph transcendental
philosophy has been taken as unique among speculative [_i.e._
theoretical] sciences; in the fourth paragraph mathematics is placed
alongside it.
Examination of this section as a whole (and the same is true of the
immediately following section) justifies the conclusion that at the time
when it was written Kant regarded the Ideas of Reason as having a purely
and exclusively regulative function, and consequently as exhausting
their inherent meaning in their empirical reference. He regards them as
entirely lacking in metaphysical significance. They are invented by
Reason for Reason’s own satisfaction, and must therefore yield in their
internal content the explanation of their existence, and must also
supply a complete and thorough answer to all problems which are
traceable to them. A dogmatic (_i.e._ ontological) solution of the
antinomies is, as we have already found, impossible; the Critical
solution considers the question subjectively,
“...in accordance with the foundation of the knowledge upon which
it is based.”[1538] “For your object is only in your brain, and
cannot be given outside it; so that you have only to take care to
be at one with yourself, and to avoid the amphiboly which
transforms your Idea into a supposed representation of an object
which is empirically given and therefore to be known according to
the laws of experience.”[1539]
Kant’s argument in proof of this purely subjective interpretation of the
Ideas consists in showing that they are not presented in any given
appearances, and are not even necessary to explain appearances. The
unconditioned, whether of quantity, of division, or of origination, has
nothing to do with any experience, whether actual or possible.
“You would not, for instance, in any wise be able to explain the
appearances of a body better, or even differently, if you assumed
that it consists either of simple or of inexhaustibly composite
parts; for neither a simple appearance nor an infinite composition
can ever come before you. Appearances demand explanation only in so
far as the conditions of their explanation are given in perception,
[and the unconditioned can never be so given].”[1540]
This standpoint, at once sceptical and empirical, is further developed
in the next section.