It must be freely admitted that there is a sort of circle here
from which it seems impossible to escape. In the order of efficient
causes we assume ourselves free, in order that in the order of ends we
may conceive ourselves as subject to moral laws: and we afterwards
conceive ourselves as subject to these laws, because we have
attributed to ourselves freedom of will: for freedom and
self-legislation of will are both autonomy and, therefore, are
reciprocal conceptions, and for this very reason one must not be
used to explain the other or give the reason of it, but at most only
logical purposes to reduce apparently different notions of the same
object to one single concept (as we reduce different fractions of
the same value to the lowest terms).

One resource remains to us, namely, to inquire whether we do not
occupy different points of view when by means of freedom we think
ourselves as causes efficient a priori, and when we form our
conception of ourselves from our actions as effects which we see
before our eyes.

It is a remark which needs no subtle reflection to make, but which
we may assume that even the commonest understanding can make, although
it be after its fashion by an obscure discernment of judgement which
it calls feeling, that all the "ideas" that come to us involuntarily
(as those of the senses) do not enable us to know objects otherwise
than as they affect us; so that what they may be in themselves remains
unknown to us, and consequently that as regards "ideas" of this kind
even with the closest attention and clearness that the understanding
can apply to them, we can by them only attain to the knowledge of
appearances, never to that of things in themselves. As soon as this