conquer them by means of reason, not in the future, but in the
present, simultaneously with the thought; he must judge that he can do
what the law unconditionally commands that be ought.

  Now the power and resolved purpose to resist a strong but unjust
opponent is called fortitude (fortitudo), and when concerned with
the opponent of the moral character within us, it is virtue (virtus,
fortitudo moralis). Accordingly, general deontology, in that part
which brings not external, but internal, freedom under laws is the
doctrine of virtue.

  Jurisprudence had to do only with the formal condition of external
freedom (the condition of consistency with itself, if its maxim became
a universal law), that is, with law. Ethics, on the contrary, supplies
us with a matter (an object of the free elective will), an end of pure
reason which is at the same time conceived as an objectively necessary
end, i.e., as duty for all men. For, as the sensible inclinations
mislead us to ends (which are the matter of the elective will) that
may contradict duty, the legislating reason cannot otherwise guard
against their influence than by an opposite moral end, which therefore
must be given a priori independently on inclination.

  An end is an object of the elective will (of a rational being) by
the idea of which this will is determined to an action for the
production of this object. Now I may be forced by others to actions
which are directed to an end as means, but I cannot be forced to
have an end; I can only make something an end to myself. If,
however, I am also bound to make something which lies in the notions
of practical reason an end to myself, and therefore besides the formal
determining principle of the elective will (as contained in law) to
have also a material principle, an end which can be opposed to the end
derived from sensible impulses; then this gives the notion of an end
which is in itself a duty. The doctrine of this cannot belong to
jurisprudence, but to ethics, since this alone includes in its
conception self-constraint according to moral laws.

  For this reason, ethics may also be defined as the system of the
ends of the pure practical reason. The two parts of moral philosophy
are distinguished as treating respectively of ends and of duties of
constraint. That ethics contains duties to the observance of which one
cannot be (physically) forced by others, is merely the consequence
of this, that it is a doctrine of ends, since to be forced to have
ends or to set them before one's self is a contradiction.

  Now that ethics is a doctrine of virtue (doctrina officiorum
virtutis) follows from the definition of virtue given above compared
with the obligation, the peculiarity of which has just been shown.
There is in fact no other determination of the elective will, except
that to an end, which in the very notion of it implies that I cannot
even physically be forced to it by the elective will of others.
Another may indeed force me to do something which is not my end (but
only means to the end of another), but he cannot force me to make it
my own end, and yet I can have no end except of my own making. The
latter supposition would be a contradiction- an act of freedom which
yet at the same time would not be free. But there is no
contradiction in setting before one's self an end which is also a
duty: for in this case I constrain myself, and this is quite
consistent with freedom.* But how is such an end possible? That is now
the question. For the possibility of the notion of the thing (viz.,
that it is not self-contradictory) is not enough to prove the
possibility of the thing itself (the objective reality of the notion).

  *The less a man can be physically forced, and the more he can be
morally forced (by the mere idea of duty), so much the freer he is.
The man, for example, who is of sufficiently firm resolution and
strong mind not to give up an enjoyment which he has resolved on,
however much loss is shown as resulting therefrom, and who yet desists
from his purpose unhesitatingly, though very reluctantly, when he
finds that it would cause him to neglect an official duty or a sick
father; this man proves his freedom in the highest degree by this very
thing, that he cannot resist the voice of duty.

  II. Exposition of the Notion of an End which is also a Duty

  We can conceive the relation of end to duty in two ways; either
starting from the end to find the maxim of the dutiful actions; or
conversely, setting out from this to find the end which is also
duty. jurisprudence proceeds in the former way. It is left to
everyone's free elective will what end he will choose for his
action. But its maxim is determined a priori; namely, that the freedom
of the agent must be consistent with the freedom of every other
according to a universal law.

  Ethics, however, proceeds in the opposite way. It cannot start
from the ends which the man may propose to himself, and hence give
directions as to the maxims he should adopt, that is, as to his
duty; for that would be to take empirical principles of maxims, and
these could not give any notion of duty; since this, the categorical
ought, has its root in pure reason alone. Indeed, if the maxims were
to be adopted in accordance with those ends (which are all selfish),
we could not properly speak of the notion of duty at all. Hence in
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.