prudence to
sin willingly than unwillingly, since rectitude of the will is
essential to prudence, but not to art. Accordingly it is evident that
prudence is a virtue distinct from art.

Reply Obj. 1: The various kinds of things made by art are all
external to man: hence they do not cause a different kind of virtue.
But prudence is right reason about human acts themselves: hence it is
a distinct kind of virtue, as stated above.

Reply Obj. 2: Prudence has more in common with art than a speculative
habit has, if we consider their subject and matter: for they are both
in the thinking part of the soul, and about things that may be
otherwise than they are. But if we consider them as virtues, then art
has more in common with the speculative habits, as is clear from what
has been said.

Reply Obj. 3: Prudence is of good counsel about matters regarding
man's entire life, and the end of human life. But in some arts there
is counsel about matters concerning the ends proper to those arts.
Hence some men, in so far as they are good counselors in matters of
warfare, or seamanship, are said to be prudent officers or pilots,
but not simply prudent: only those are simply prudent who give good
counsel about all the concerns of life.
________________________

FIFTH ARTICLE [I-II, Q. 57, Art. 5]

Whether Prudence Is a Virtue Necessary to Man?

Objection 1: It would seem that prudence is not a virtue necessary to
lead a good life. For as art is to things that are made, of which it
is the right reason, so is prudence to things that are done, in
respect of which we judge of a man's life: for prudence is the right
reason about these things, as stated in _Ethic._ vi, 5. Now art is
not necessary in things that are made, save in order that they be
made, but not after they have been made. Neither, therefore is
prudence necessary to man in order to lead a good life, after he has
become virtuous; but perhaps only in order that he may become
virtuous.

Obj. 2: Further, "It is by prudence that we are of good counsel," as
stated in _Ethic._ vi, 5. But man can act not only from his own, but
also from another's good counsel. Therefore man does not need
prudence in order to lead a good life, but it is enough that he
follow the counsels of prudent men.

Obj. 3: Further, an intellectual virtue is one by which one always
tells the truth, and never a falsehood. But this does not seem to be
the case with prudence: for it is not human never to err