Reply Obj. 1: The moral virtues are more lasting than the intellectual virtues, because they are practised in matters pertaining to the life of the community. Yet it is evident that the objects of the sciences, which are necessary and invariable, are more lasting than the objects of moral virtue, which are certain particular matters of action. That the moral virtues are more necessary for human life, proves that they are more excellent, not simply, but relatively. Indeed, the speculative intellectual virtues, from the very fact that they are not referred to something else, as a useful thing is referred to an end, are more excellent. The reason for this is that in them we have a kind of beginning of that happiness which consists in the knowledge of truth, as stated above (Q. 3, A. 6).
Reply Obj. 2: The reason why man is said to be good simply, in respect of moral virtue, but not in respect of intellectual virtue, is because the appetite moves the other powers to their acts, as stated above (Q. 56, A. 3). Wherefore this argument, too, proves merely that moral virtue is better relatively.
Reply Obj. 3: Prudence directs the moral virtues not only in the choice of the means, but also in appointing the end. Now the end of each moral virtue is to attain the mean in the matter proper to that virtue; which mean is appointed according to the right ruling of prudence, as stated in Ethic. ii, 6; vi, 13. ________________________
FOURTH ARTICLE [I-II, Q. 66, Art. 4]
Whether Justice Is the Chief of the Moral Virtues?
Objection 1: It would seem that justice is not the chief of the moral virtues. For it is better to give of one's own than to pay what is due. Now the former belongs to liberality, the latter to justice. Therefore liberality is apparently a greater virtue than justice.
Obj. 2: Further, the chief quality of a thing is, seemingly, that in which it is most perfect. Now, according to Jam. 1:4, "Patience hath a perfect work." Therefore it would seem that patience is greater than justice.
Obj. 3: Further, "Magnanimity has a great influence on every virtue," as stated in Ethic. iv, 3. Therefore it magnifies even justice. Therefore it is greater than justice.
On the contrary, The Philosopher says (Ethic. v, 1) that "justice is the most excellent of the virtues."
I answer that, A virtue considered in its species may be greater or less, either simply or relatively. A virtue is said to be greater simply, whereby a greater rational good shines forth, as stated above (A. 1). In this way justice is the most excellent of all the moral virtues, as being most akin to reason. This is made evident by considering its subject and its object: its subject, because this is the will, and the will is the rational appetite, as stated above (Q. 8, A. 1; Q. 26, A. 1): its object or matter, because it is about operations, whereby man is set in order not only in himself, but also in regard to another. Hence "justice is the most excellent of virtues" (Ethic. v, 1). Among the other moral virtues, which are about the passions, the more excellent the matter in which the appetitive movement is subjected to reason, so much the more does the rational good shine forth in each. Now in things touching man, the chief of all is life, on which all other things depend. Consequently fortitude which subjects the appetitive movement to reason in matters of life and death, holds the first place among those moral virtues that are about the passions, but is subordinate to justice. Hence the Philosopher says (Rhet. 1) that "those virtues must needs be greatest which receive the most praise: since virtue is a power of doing good. Hence the brave man and the just man are honored more than others; because the former," i.e. fortitude, "is useful in war, and the latter," i.e. justice, "both in war and in peace." After fortitude comes temperance, which subjects the appetite to reason in matters directly relating to life, in the one individual, or in the one species, viz. in matters of food and of sex. And so these three virtues, together with prudence, are called principal virtues, in excellence also.