ethics the notion of duty must lead to ends, and must on moral
principles give the foundation of maxims with respect to the ends
which we ought to propose to ourselves.

Setting aside the question what sort of end that is which is in
itself a duty, and how such an end is possible, it is here only
necessary to show that a duty of this kind is called a duty of virtue,
and why it is so called.

To every duty corresponds a right of action (facultas moral is
generatim), but all duties do not imply a corresponding right
(facultas juridica) of another to compel any one, but only the
duties called legal duties. Similarly to all ethical obligation
corresponds the notion of virtue, but it does not follow that all
ethical duties are duties of virtue. Those, in fact, are not so
which do not concern so much a certain end (matter, object of the
elective will), but merely that which is formal in the moral
determination of the will (e.g., that the dutiful action must also
be done from duty). It is only an end which is also duty that can be
called a duty of virtue. Hence there are several of the latter kind
(and thus there are distinct virtues); on the contrary, there is
only one duty of the former kind, but it is one which is valid for all
actions (only one virtuous disposition).

The duty of virtue is essentially distinguished from the duty of
justice in this respect; that it is morally possible to be
externally compelled to the latter, whereas the former rests on free
self-constraint only. For finite holy beings (which cannot even be
tempted to the violation of duty) there is no doctrine of virtue,
but only moral philosophy, the latter being an autonomy of practical