The virtuous person is the person whose reason, as Grisez expresses the matter, is “unfettered” — i.e., he or she is the one who shapes his choices and actions in accordance with the truth, the one who is in possession, through the virtues, of his or her desires and emotions and is not possessed by them.25
B. St. Thomas Aquinas on Virtue
St. Thomas’s teaching on virtue is provided in many of his writings,26 and there are several excellent studies of his thought on this matter.27
I have noted already that the principle St. Thomas uses for distinguishing among virtues — or the stable dispositions through which the acting person is able to do the good well — is based on the distinction among the operative “powers” or “faculties” of the human person. St. Thomas says that the proper subject or seat of virtue, as an operative habit (i.e., a quality disposing us to act well, i.e., to choose in accord with the truth), is some power of the soul. But the human soul has different powers; those properly the subject of virtue are those from which human acts proceed: (1) the intellect (whose operation concerns the truth, in light of which we can make choices), (2) the will (whose operation concerns choice and intention of end), and the (3) irascible and (4) concupiscible appetites, not insofar as they are sensitive powers of the soul but insofar as they “participate” in reason by obeying it, so that we can say that “the virtue which is in the irascible and concupiscible powers is nothing else but a certain habitual conformity of these powers to reason.”28
“Qualities” or “habitus” of the intellect through which it can carry out its operations well are intellectual virtues. As we have seen already, some of these are virtues in a relative sense inasmuch as they enable the person to do some things well, i.e., (1) to understand (the virtue of understanding or intellectus, which embraces not only “intellectus” — understood as our grasp of the first principles of speculative inquiry — but also what St. Thomas called synderesis or our habitual grasp of the first principles of practical reasoning), (2) to know things in their causes (knowledge or scientia), (3) to grasp the deepest causes of things (wisdom or sapientia), and (4) to make things (art). Virtue in the strict sense, however, not only enables a person to do things well but also makes its possessor good and his work [human act] good likewise. This kind of virtue also exists in the intellect insofar as it is moved by the will. A supernatural virtue of this kind perfects the speculative intellect, namely, the virtue of faith. The natural virtue perfecting the intellect is the virtue of prudence, which perfects reason as practical, not speculative.29 And prudence, St. Thomas insists, requires moral virtue and is itself moral virtue.
“Since prudence is the right reason of things to be done,” he writes:
It is a condition thereof that man be rightly disposed in regard to the principles of this reason of things to be done, that is, in regard to their ends, to which man is rightly disposed by the rectitude of the will.… Therefore, just as the subject of [the virtue] of science or understanding, which is right reason with respect toward beings whose truth is to be contemplated, is the speculative intellect in its relationship to the agent intellect [through whose light we can come to grasp the essences of things], so the subject of [the virtue] of prudence is the practical intellect in its relationship to a rectified will.30
Of the virtues perfecting a person through his intellect, then, the only one that is a moral virtue — one that makes not only the person’s “work” good but also the person himself or herself — is that of prudence.
In Summa theologiae (q. 58, a.2), Thomas further discusses more fully how moral virtue differs from a purely intellectual virtue. There he writes:
… for a man to act rightly, it is requisite not only that his reason be well disposed by means of a habit of intellectual virtue, but also that his appetitive power [and he has three such appetitive powers: the will, and two sensitive appetites, the concupiscible and irascible] be well disposed by means of a habit of moral virtue. And so moral virtue differs from intellectual virtue, even as appetite differs from reason. Hence, just as appetite is the principle of human acts in so far as it partakes of reason in some way, so a moral habit has the meaning of human virtue insofar as it is in conformity with reason.31
This text prepares the way for Aquinas’s division of the moral virtues perfecting the appetites into the classical “cardinal” virtues, namely, those of prudence (perfecting one’s practical reason), justice (perfecting the appetite of the will), temperance (perfecting the concupiscible appetite), and fortitude (perfecting the irascible appetite).32
Prudence, in other words, presupposes that a person be rightly disposed inwardly to the “ends” or “goods” of human action, because a person’s moral choices involve affective knowledge or judgments to which assent is given on the basis of appetitive dispositions. Consequently, a person’s appetites must be rightly disposed toward the “ends” or “goods” of human conduct if he or she is to make prudent judgments.33 Prudence is “right reason about things that are to be done” (recta ratio agibilium),34 because it is reason rectified by right appetite: the appetite of the will being rectified by the virtue of justice, the concupiscible appetite by the virtue of temperance, and the irascible appetite by the virtue of courage or fortitude.
In an illuminating passage in which he shows that fortitude is a virtue necessary for a good moral life, St. Thomas clearly expresses his thought on the cardinal virtues and their role in the moral life. In it he writes:
As Aristotle says, “a virtue is what makes the one who has it good, and good too his activity.” But the good of man is to be in accord with reason.… It follows that it pertains to human virtue that it make a human being and his activity to be in accord with reason. But this happens in three ways. In one way insofar as reason itself is made right, and this is done through the intellectual virtues (of which prudence is chief). In another way, insofar as the very rectitude of reason is instituted in human affairs, and this belongs to justice. In a third way, insofar as impediments to this rectitude are removed. But the human will can be hindered in two basic ways from putting the order required by reason into human affairs. In one way, from the fact that it is so strongly attracted by some delightful good that it fails to bring about the good required by reason; and this impediment is removed by the virtue of temperance. In another way, from the fact that it is kept from doing what is good on account of some terrible difficulty that it encounters. And for removing this impediment the virtue of fortitude is required, a fortitude or courage of the mind or spirit, whereby the person resists this difficulty, just as through bodily courage he overcomes and resists bodily impediments. It is thus evident that fortitude is a virtue insofar as it makes man conform to reason.35
The foregoing offers a summary of the teaching of St. Thomas on the acquired natural virtues. I will not here consider his teaching on the theological virtues of faith, hope, and charity and his teaching that, with charity, God infuses supernatural moral virtues of prudence, justice, fortitude, temperance, etc. These aspects of his teaching are well set forth by Romanus Cessario in The Moral Virtues and Theological Ethics and Virtue or the Examined Life. An excellent brief account of Thomas’s teaching on the virtues can be found in T. C. O’Brien’s article on virtue in the New Catholic Encyclopedia.36
C. Virtue-based Ethics and Principles-based Ethics
Some today oppose a