Aquinas and Unity of Virtues

imagesThe problem of connection of virtues is about whether one can have a perfect virtue without having the other perfect virtues. Aquinas claims that, unlike imperfect virtues, the perfect virtues are connected, and one cannot have perfect virtues without the others. Furthermore, he argues that the relationship between moral virtues and prudence is a mutual entailment, i.e. one cannot have moral virtues without prudence or prudence without moral virtues. On the other hand, Abelard’ philosopher denies Aquinas’s claim that prudence is a moral virtue per se. Abelard’s philosopher argues that 1) prudence although necessary for moral virtues, it is not a virtue itself and 2) Prudence is the knowledge that makes a person able to distinguish between good and bad. As he puts it, “Certainly prudence is this knowledge of morals that is called, as a certain treatise on ethics transmits to us, the ‘science of good and evil things’—discerning goods or evils that in themselves are properly to be called good or evils” (DPC 265).[1] And 3) the good and bad both can have prudence. In fact, Abelard’s philosopher argues that virtues are connected, but to him, what connects virtues is an internal interdependency type of relationship between moral virtues. I found Aquinas’s second argument, presented in Summa Theologiae 1.56.1 R) more convincing than Abelard’s philosopher inconsistent argument about the relationship between prudence and moral virtues. I shall first sketch both philosophers’ arguments then explain why I think Aquinas makes a stronger case.

Before reformulating Aquinas argument for the mutual entailment of the moral virtues and prudence, highlighting some preliminary points are necessary in order to understand his argument better. For Aquinas a virtue, “disposes an agent to perform its proper operation or movement” ST IaIIae 49.1). On the other hand, prudence for Aquinas is the practical wisdom that enables one to choose a proper mean suitable for a proper end. As he puts it, prudence is a “certain rectitude of discretion in any actions or matters whatever” (ST IaIIae 61.4). It is necessary to know that prudence for Aquinas is not same as cleverness. The former is not compatible with moral virtues while the latter is compatible with moral virtues. For instance, one may plan a murder cleverly; however, this is not an act of prudence for Aquinas. An evil person can be clever but not prudent. However, it seems that this the point that Abelard’s philosopher and Aquinas differ, for Abelard’s philosopher believes that both the good and bad can have prudence.

Aquinas presents a bi-conditional argument for mutual entailment of moral virtues and prudence. For him, there are two conditions for any morally significant action. The first is general moral principles that govern actions, and the second is applying those general principles in a particular circumstance.

Aquinas’s argument for mutual entailment of prudence and moral virtues can be formulated as follows:

  • To reach an end, it is necessary to choose means that are suitable to the end.
  • Moral virtues set proper ends, and dispose an agent to act virtuously.
  • Prudence is the practical wisdom to choose means suitable to the ends.
  • Prudence does not determine the end (moral virtues).
  • Therefore, there is no moral virtue without prudence.
  • Therefore there is no prudence without moral virtues.

To Aquinas, perfect virtues are justice, prudence, courage, and moderation. Unlike imperfect moral virtues, perfect moral virtues are connected. Aquinas defines a perfect moral virtue as, “a habit that inclines one to perform good deed well” (ST 1.65.1 R). However, inclination by itself is not sufficient for making the right choice. As he puts it, “For it is proper to moral virtue to make the right choice, since it is an elective disposition (habitus). But an inclination for the proper end, directed by the habit of moral virtue, does not suffice for right choice” (St 1.65.1 R. I.51-57). Moral virtues set proper ends; however, a proper end or an inclination for seeking proper ends is not sufficient for choosing proper means. Therefore, one cannot accomplish those ends without prudence. A physician may know all of the theoretical knowledge and the first principles of his science; however, if he lacks prudence, he will not be able to apply his knowledge properly on a particular patient and disease. By the same token, a person needs prudence to know how to do his/her moral virtues well. Another example that reveals the dependency of moral virtues on prudence is that if a just person lacks prudence, this deficiency destroys his/her justice. The classical example is the imprudent just person who wants to do his/her moral duty and returns someone’s sword when the owner is drunk and angry. In this case, the lack of prudence destroys his justice, because an angry drunk who owns a sword might harm innocent people, and it is not compatible with justice. Therefore, there is no moral virtue without prudence.

On the other hand, the second part of the bi-conditional argues that there is no prudence without moral virtues. Prudence does not establish the end. Prudence is a practical knowledge of how to apply universal principles in a particular situation; however, it establishing the end requires the knowledge of universals. As he puts it, “For [prudence] is right reason concerning what is to be done, which proceeds as from [the first] principles from the goals (fines) [we set about] what can be done, the goals to which a person is rightly related by the moral virtues” (ST 1.56.1 R, I 57-60). He maintains that finding the means to achieve wicked end causes by lack of prudence. Therefore, he concludes, there is no prudence without moral virtues.

Abelard’s philosopher views prudence as the mother or the origin of moral virtue; however, unlike Aquinas, he claims that it is compatible with evil ends. In other words, for Aquinas, prudence is not compatible with cleverness whereas for Abelard’s philosopher a clever person can be prudent too. For Abelard’s philosopher, prudence is necessary for having moral virtues. However, the good and the evil both might have prudence (DPC 258). If, as Abelard’s philosopher understands, prudence is “science of good and evil” (DPC 256), then the good and evil can have this knowledge. Furthermore, this science per se does not make a person good or bad. For Abelard’s philosopher, in addition to the science of good and evil, 1) good intention and 2) strength of the will/mind are necessary for moral actions. He states, “Therefore, we call both of these a kind of firmness and steadiness of the mind whereby we are enabled to carry out what we want through justice. Their contraries are indeed rightly called a kind of mental weakness or inabilities to resist vices (267). He defines virtue as “the mind’s best habit” (DPC 254) that is attainable through repetitive practices so that a virtuous person would act virtuously against all the obstacles and temptations (DPC 266). A vice, on the contrary, is the opposite of virtue, so the mind’s worse habit” that makes a person act viciously. It seems that Abelard’s philosopher would reject the second half of Aquinas bi-conditional, i.e., no prudence without moral virtues. Therefore, unlike Aquinas the notion of a wicked prudent person is not an inconsistent notion, to Abelard’s philosopher.

I tend to agree with Aquinas on his account that there is no prudence without moral virtues. One may agree with Abelard’s philosopher that prudence is not a moral virtue per se; however, he does not make a convincing case when he argues that prudence is compatible with moral vices. In fact, he reduces the scope of prudence to merely a “science of good and evil,” which lacks to determine right choices. Abelard’s philosopher on the one hand believes that prudence is the mother or origin of moral virtues; on the other hand, he maintains that prudence can be shared by the good and the bad equally. I think Aquinas is right to reject the latter claim, since 1) prudence is not merely a “science of good and evil” and 2) it is to know how to act virtuously in a particular situation. Therefore, I think Aquinas make a stronger case.


[1] In 256, Abelard’s philosopher mentions “some people” who calls “prudence’s discernment the mother or origin of the virtues rather than itself a virtue.” It seems that it is also Abelard’s view too. In his Ethics 227, he reiterates the same point. He states, “Prudence—that is, the discrimination of good and evil—is the mother of virtues rather that itself a virtue.” Regardless, to say that Abelard’s philosopher holds the view that prudence is necessary for moral virtue is a matter of interpretation of his characterization of prudence as “mother of virtues.” If an offspring cannot come into existence without a mother, then having a mother is a necessary condition for birth; however, it is not a sufficient condition, since birth requires a father too. If this is the analogy the Abelard’s philosopher has in mind, then his position on the insufficiency of prudence is not fundamentally different from Aquinas. Since Aquinas also maintains that there is no moral virtue without prudence. However, as we will see Abelard’s philosopher reject the second part of the bi-conditional, i.e., no prudence without moral virtues.


Abelard and Religious Laws

images-3            In his dialogue with a defender of Mosaic Law, the philosopher denies the spiritual merits of the Mosaic Law (ML). The philosopher maintains that the ML is neither necessary nor sufficient for bringing spiritual rewards. He argues that it is not necessary, since the Natural Law (NL) offers what is required for bringing the spiritual rewards. To the philosopher, the spiritual rewards granted by God for one’s good and correct intentions rather than the external aspects of deeds. The Law, to him, is concerned with external aspects of the deeds; therefore, insufficient for spiritual rewards. On the other hand, the defender of ML finds the philosopher’s anti-law claims problematic; he claims that ML entails the Natural Law and can bring spiritual rewards if they are conducted with a good intention. I argue that the philosopher makes a stronger case for the non-necessity and insufficiency of ML for bringing of spiritual rewards. First, however, I sketch the structures of the philosopher’s arguments about superfluousness of ML for bringing spiritual rewards.

The philosopher’s argument for non-necessity of ML can be formulated as follows:

  1. If ML were necessary for bringing spiritual rewards, then it would be primary and universal.
  2. ML is not primary.
    1. Temporally, it is not prior to NL.
    2. Metaphysically, it is not prior to NL.
  3. ML is not universal.
    1. NL is universal and is prior to ML.
  4. Therefore, ML is not necessary.

The conclusion necessarily follows from the premises, so it is a valid argument. To the philosopher, it is false to believe that spiritual rewards are contingent on ML. Perhaps, because spiritual rewards were possible prior to ML. If spiritual rewards were possible before ML, it implies that ML is neither primary (temporally or metaphysically)

nor universal. Furthermore, the Jew also admits that ML only became obligatory after its creation, not for everyone, but only for Jews. Therefore, it is convincing to believe that ML is neither primary nor universal.

The philosopher’s argument for the temporal primacy of the NL is that the simpler is prior to the more complex things, since complex things are composite of simple things. Therefore, the existence of more complex things is dependence the existence of simpler thing both temporally and metaphysically. Indeed, the NL is simpler than any religion. It existed prior to any religion including ML; therefore, NL is prior to ML, and the latter is dependent on the former.

After the philosopher has argued for non-necessity of ML, he argues for the insufficiency of ML. His argument can be formulated as follows:

  1. A good intention and being right about a deed is what makes an action meritorious. (Ethics 106-109; DPJ 133)
  2. Exterior deeds are not sufficient for spiritual rewards.
  3. ML is mostly concerned with external deeds.
  4. Therefore, ML is insufficient for bringing spiritual rewards.

After establishing the insufficiency of ML, the Philosopher maintains that only love of God suffices to bring spiritual rewards.

The Jew admits that ML is incomplete even based on his own religious believes. It was incomplete because after ML, new sets of religious laws were created for the Jewish community. However, the Jew tries to make a case for possibility of ML bringing spiritual rewards. He maintains that reason neither can affirm nor deny the divine origin of the Law. Hence, obeying ML is a matter of prudence, since many wise authorities have believed that obeying ML is more prudent than ignoring it. Furthermore, despite the philosopher’s anti-law contention, the Jew maintains that ML includes NL and offers spiritual rewards. The Jew also correctly states that obeying ML can be out of love of God rather than seeking earthly rewards, since there is nothing in sincere obedience to ML that makes it incompatible with love of God in the heart.

The Jew puts forwards several arguments against the philosopher’s claims that ML is neither necessary nor sufficient: 1) ML offers more spiritual rewards than NL 2) obeying ML is compatible with the love of God. Do these two arguments undermine the philosopher’s argument about non-necessary and insufficiency of ML? I do not think it does. First, the philosopher may respond that what the Jew claims that ML offers more spiritual rewards is only another type of earthly rewards. For instance, circumcision and purification rituals and their subsequent spiritual rewards that the Jew mentions, such as preserving the unity of religious community in the case of purification rituals and also his emphasis on the symbolic meaning of circumcision that signifies a break with early attachments, can be affirmed by NL independent from ML. Therefore, it seems that the philosopher make a stronger case for 1) Religious laws are neither necessary nor sufficient, 2) All one needs for salvation is love of God, and 3) Love of God can be affirmed by NL independently from ML is more convincing than appealing to religious laws which are neither universal nor fundamental.