Reply Obj. 1: This is not a definition of virtue in general, but of moral virtue, the definition of which fittingly includes an intellectual virtue, viz., prudence, which has the same matter in common with moral virtue; because, just as the subject of moral virtue is something that partakes of reason, so moral virtue has the aspect of virtue, in so far as it partakes of intellectual virtue.
Reply Obj. 2: This argument proves that prudence helps all the virtues, and works in all of them; but this does not suffice to prove that it is not a special virtue; for nothing prevents a certain genus from containing a species which is operative in every other species of that same genus, even as the sun has an influence over all bodies.
Reply Obj. 3: Things done are indeed the matter of prudence, in so far as they are the object of reason, that is, considered as true: but they are the matter of the moral virtues, in so far as they are the object of the appetitive power, that is, considered as good. _______________________
SIXTH ARTICLE [II-II, Q. 47, Art. 6]
Whether Prudence Appoints the End to Moral Virtues?
Objection 1: It would seem that prudence appoints the end to moral virtues. Since prudence is in the reason, while moral virtue is in the appetite, it seems that prudence stands in relation to moral virtue, as reason to the appetite. Now reason appoints the end to the appetitive power. Therefore prudence appoints the end to the moral virtues.
Obj. 2: Further, man surpasses irrational beings by his reason, but he has other things in common with them. Accordingly the other parts of man are in relation to his reason, what man is in relation to irrational creatures. Now man is the end of irrational creatures, according to Polit. i, 3. Therefore all the other parts of man are directed to reason as to their end. But prudence is "right reason applied to action," as stated above (A. 2). Therefore all actions are directed to prudence as their end. Therefore prudence appoints the end to all moral virtues.
Obj. 3: Further, it belongs to the virtue, art, or power that is concerned about the end, to command the virtues or arts that are concerned about the means. Now prudence disposes of the other moral virtues, and commands them. Therefore it appoints their end to them.
On the contrary, The Philosopher says (Ethic. vi, 12) that "moral virtue ensures the rectitude of the intention of the end, while prudence ensures the rectitude of the means." Therefore it does not belong to prudence to appoint the end to moral virtues, but only to regulate the means.
I answer that, The end of moral virtues is human good. Now the good of the human soul is to be in accord with reason, as Dionysius declares (Div. Nom. iv). Wherefore the ends of moral virtue must of necessity pre-exist in the reason.