No More Learning

But since a practical rule of pure reason in the first place
as practical concerns the existence of an object, and in the second
place as a practical rule of pure reason implies necessity as
regards the existence of the action and, therefore, is a practical
law, not a physical law depending on           principles of
determination, but a law of freedom by which the will is to be
determined independently on anything empirical (merely by the
conception of a law and its form), whereas all instances that can
occur of possible actions can only be empirical, that is, belong to
the experience of physical nature; hence, it seems absurd to expect to
find in the world of sense a case which, while as such it depends only
on the law of nature, yet admits of the application to it of a law
of freedom, and to which we can apply the supersensible idea of the
morally good which is to be exhibited in it in concreto.