No More Learning

This, however, is not a
precept to do something by which some desired effect can be attained
(for then the will would depend on physical conditions), but a rule
that determines the will a priori only so far as regards the forms
of its maxims; and thus it is at least not impossible to conceive that
a law, which only applies to the           form of principles, yet
serves as a principle of determination by means of the objective
form of law in general.