PROLEGOMENA TOANYFUTUREMETAPHYSICS 839
§ 60. Thus we have fully exhibited metaphysics, in its subjective possibility, as it
is actually given in the natural predisposition of human reason and in that which consti-
tutes the essential end of its pursuit. Though we have found that this merely natural use
of such a predisposition of our reason, if no discipline arising only from a scientific
critique bridles and sets limits to it, involves it in transcendent and specious inferences
and really conflicting dialectical inferences, and this fallacious metaphysics is not only
unnecessary as regards the promotion of our knowledge of nature but even disadvanta-
geous to it, there yet remains a problem worthy of investigation, which is to find out the
natural ends intended by this disposition to transcendent concepts in our nature, because
everything that lies in nature must be originally intended for some useful purpose.
Such an inquiry is of a doubtful nature, and I acknowledge that what I can say
about it is conjecture only, like every speculation about the ultimate ends of nature.
Such conjecture may be allowed me here, for the question does not concern the objec-
tive validity of metaphysical judgments but our natural predisposition to them, and
therefore does not belong to the system of metaphysics but to anthropology.
When I compare all the transcendental Ideas, the totality of which constitutes the
proper problem of natural pure reason, compelling it to quit the mere contemplation of
nature, to transcend all possible experience, and in this endeavor to produce the thing (be it
knowledge or fiction) called metaphysics, I think I perceive that the aim of this natural ten-
dency is to free our concepts from the fetters of experience and from the limits of the mere
contemplation of nature so far as at least to open to us a field containing mere objects for
the pure understanding which no sensibility can reach, not indeed for the purpose of spec-
ulatively occupying ourselves with them (for there we can find no ground to stand on), but
in order that practical principles [may be assumed as at least possible]; for practical princi-
ples, unless they find scope for their necessary expectation and hope, could not expand to
the universality which reason unavoidably requires from a moral point of view.
So I find that the psychological Idea (however little it may reveal to me the nature of
the human soul, which is elevated above all concepts of experience), shows the insuffi-
ciency of these concepts plainly enough and thereby deters me from materialism, a psy-
chological concept which is unfit for any explanation of nature and which moreover
confines reason in practical respects. The cosmological Ideas, by the obvious insuffi-
ciency of all possible knowledge of nature to satisfy reason in its legitimate inquiry, serve
in the same manner to keep us from naturalism, which asserts nature to be sufficient for
itself. Finally, all natural necessity in the sensible world is conditional, as it always pre-
supposes the dependence of things upon others, and unconditional necessity must be
sought only in the unity of a cause different from the world of sense. But as the causality
of this cause, in its turn, were it merely nature, could never render the existence of the con-
tingent (as its consequent) comprehensible, reason frees itself by means of the theological
Idea from fatalism (both as a blind natural necessity in the coherence of nature itself, with-
out a first principle, and as a blind causality of this principle itself) and leads to the con-
cept of a cause possessing freedom or of a Supreme Intelligence. Thus the transcendental
Ideas serve, if not to instruct us positively, at least to destroy the narrowing assertions of
materialism, of naturalism, and of fatalism, and thus to afford scope for the moral Ideas
beyond the field of speculation. These considerations, I should think, explain in some
measure the natural predisposition of which I spoke.
The practical value, which a merely speculative science may have, lies without the
bounds of this science, and can therefore be considered as a scholium merely, and like all
scholia does not form part of the science itself. This application, however, surely lies
within the bounds of philosophy, especially of philosophy drawn from the pure sources
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