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What can Aquinas teach us about Virtue?

Virtue Ethics Matter

If you want to end a conversation with someone at a party tell them you study the virtue ethics of Thomas Aquinas. What possible reason could there be for doing this?

My goal in this article is to answer this question. I want to show why virtue ethics matters, and why Thomas Aquinas is a good theological guide for understanding it. Virtue ethics matters because we need to pay attention to of what sort of people we are becoming and that we make deliberate choices about who we want to become. We are neither hopelessly stuck nor free to be whatever we choose to be at any given moment. We are stewards or gardeners of our character and our bodies by the grace and power of God. Virtue ethics helps us to think well about how we participate in our formation. Virtue ethics matters because we need to pay attention to of what sort of people we are becoming. Click To Tweet

Why Virtue Ethics? Evangelicals and their debt to modern ethical theories

I’ve taught on virtue ethics at a graduate level several times. These courses are arranged by ethical theories and ethical issues. The goal of these courses is typically to answer the big pressing cultural questions. Is this wrong? Is that right? Typically, virtue ethics fits alongside the other major modern ethical theories, deontology and consequentialism (especially Kant and Mill).

As I teach these approaches—virtue ethics, deontology, and consequentialism, I can’t help hearing in my head the old Sesame Street song, “One of these things is not like the others, one of these things is not the same.” The problem is that modern ethics is obsessed with the question how do we know what is a right action versus a wrong one?

By contrast virtue ethics is moral psychology embedded in a political philosophy. It answers the question, what is a good human person? How do I become good? And, how is society related to human goodness and formation? 

My big problem in teaching virtue ethics to evangelical students is convincing them that their default mode in answering ethical questions is too narrow. They smuggle in all sorts of unhelpful assumptions from enlightenment moral philosophy. They focus primarily on what is right or wrong and whether or not they can find appropriate biblical texts to prove whether an action is right or wrong. They tend not to think very deeply about formation. Evangelicals smuggle in all sorts of unhelpful assumptions from enlightenment moral philosophy. Click To Tweet

Because of this default mode, Christians have also been regrettably obtuse about the formation of emotional states and mental health problems. We tend to focus on whether emotional states like anxiety are right or wrong as if they are sinful acts. On this view, anxiety is wrong in the same way that slapping someone might be wrong. And if being anxious is a sin, then we ought not to do it. In the immortal words of Bob Newhart’s Dr. Switzer, “STOP IT.”

This narrow view of my students does not account for how a person might gradually become more or less anxious as a longstanding quality of their whole person. It does not account for a process by which anxiety might be overcome. Within the virtue ethics tradition, the term for a negative psychological quality is vice. Vice is a habit (quality) of my powers that hinders them from working well. A vicious person (someone characterized by vice) might be overly fearful easily angered, or passionately lustful. Vice involves excess, both too much and too little. Courage has an appropriate amount of resolve in the face of danger, neither cowardly or reckless. But virtue might be put on through wisdom and practice; a cowardly person might become bolder while a reckless person might become more prudent.

These are the sorts of issues that moral psychology addresses. How do I make good use of my capacities for thought, choice, intuition, and feeling? What is wisdom? How do my choices form me? How should my emotional states be regulated? How do I become virtuous? How is God involved? Without a moral psychology, the answers to these questions are not obvious. And this is precisely what virtue ethics gives us, a moral psychology. Moral psychology is the study of moral capacities, moral identity, and especially the development of character. Evangelicals focus primarily on whether they can find a biblical texts to prove whether an action is right or wrong. They tend not to think very deeply about formation. Click To Tweet

The narrow view of my students has an underdeveloped moral psychology where people are thinking and choosing beings held responsible for their beliefs (true or false) and the choices (or emotions) that these beliefs produce. The relevant question is whether these choices or emotions are right or wrong. If they are wrong, then we need to think better about it. The goal of ethics is to tell us what is right or wrong and compel us to choose right. Modern ethics has little to no place for gradually cultivating psychological habits.

Virtue Ethics of Thomas Aquinas

A more satisfying view is present in the theological moral psychology of Thomas Aquinas. Moral psychology was at the center (literally) of Aquinas’ Summa Theologica. Mark Jordan writes, “I believe that Thomas wrote the Summa for the sake of the second part—that is, in order to situate the moral component of theology within a properly ordered account of the whole.”[1]

The Summa is structured according to an exitus-reditus theme (going out and coming back); the moral theology of part two is the crucial hinge.[2] Part 2-1 describes the final end of humanity (beatitude in comprehending God) and how to arrive at it. Aquinas describes our actions and passions, the nature of habit, and then specifically the virtues and vices, the habits that dispose us toward beatitude or away from it. Part 2-2 gets into the particulars of the four cardinal virtues, the three theological virtues, and the gifts of the Spirit. Of the 512 questions in the Summa, Aquinas’ moral theology accounts for 303 of them.

So, the core Summa is an exploration of moral psychology, what it means to be human, the human capacity for formation, and the nature of that formation. I want to highlight four features of Aquinas’ view that help us pay attention to our formation, what sort of people we are becoming and to make deliberate choices that, by the power of Spirit, cultivate renewed human agency. The four features are dualistic holism of body and soul, dual process psychology, formation as habit, and theological integration.

Dualistic Holism

A hallmark of enlightenment ethics is an overemphasis on moral epistemology (how do we know what is right?) as rule- or law-governed.[3] This rationalist bent tends to see the body as incidental or an obstacle to ethical behavior. The passions of the body cloud reason’s judgment. The result is that the body plays little to no positive role in ethics. It is a potential liability, but not an asset. The psychology of Thomas Aquinas does acknowledge that our passions impede reason’s judgments and the will’s choices. However, his psychology also acknowledges a productive role the passions play in moral formation, and therefore a productive role for the body.

The key to understanding the role the body plays is in understanding how Aquinas conceives of human nature. He argues for a hylomorphic view (form and matter) of body and soul where the soul just is the life form of the body. The soul is not the Cartesian “thinking thing,” but the principle of life for the whole person and whole body. It accounts not just for rational thought but also for the lower powers responsible for basic subsistence and quasi-rational bodily reactions to our environment.

For Aquinas there are three layers:

  1. rational powers (intellect and will)
  2. vegetative powers
  3. animal (or sensitive) powers

The vegetative powers accomplish basic survival functions like digestion, healing, and breathing. The sensitive powers are divided into sense appetite (passions) and sense apprehension (perception). The lower the powers, the more bodily involving the power.

The passions, which are a reasonable approximation for what psychologists call emotions, are movements of the soul (attraction, aversion, etc.) involving bodily change (heating, cooling, etc.).  The passions operate “by means of a corporeal organ,”[4] especially the heart. The conditions or “climate” of the body can dispose a person to certain passions. On Galenist medical theory, a heart that is already heated is more prone to anger. Even longstanding personality temperaments may have an impact on the passions. A person who is temperamentally hot and dry (choleric) “gets angry more readily.”[5] But the body is not merely negatively involved, dispositions, health, and habits of virtue that form in the body/soul unity may dispose a person toward positive traits.[6]

Clearly, in Aquinas’ moral psychology the body is involved in moral formation because of his hylomorphic unity of body and soul. The body potentially can be habituated in virtuous or vicious ways. And this means that there are both moral and non-moral influences on our passions (e.g., health or evil desire). To Aquinas, the body relevant to moral concerns, and our souls are susceptible to bodily weakness. Sin and illness are intertwined in this unity. A wise person must understand the complex conditions of our bodies and the ways that thoughts/choices and experiences (or sin and suffering) combine to form us.

Dual Process Psychology

I have already stated that Aquinas specifies three layers of powers: rational, sensitive, and vegetative. This way of arranging our powers is prescient regarding recent development in cognitive science. It is also quite helpful for understanding moral formation. The key to understanding this is seeing what the respective powers do and how the lower powers are ultimately governed by the higher.

According to Aquinas the lower functions of perception and passion operate somewhat independently of reason and will. Perception is broadly informed by reason but does not consult it in the moment of seeing. Perception makes a quick judgment about what it is seeing and the significance of it. Perception might see a wolf and conclude that it is dangerous. The passions will follow this judgment in arousing feelings of fear and beginning to move the body away from the wolf. At this point in Aquinas’ action theory, reason and will have not yet had their say.

Jonathan Haidt, a contemporary advocate of dual process theory, analogizes the relationship between our upper and lower powers as a man riding an elephant.[7] The man may have well-formed ideas about where he wants to go, but the elephant has a mind of its own. Haidt argues that the elephant is really in charge. In this respect Haidt is a good student of David Hume. Hume taught that passions really motivate us and reason is a slave to them. Haidt suggests that our rational powers follow our passions and act like a good lawyer, giving reasons why our intuitions are correct.Thomas Aquinas has a different view of virtue than David Hume. Click To Tweet

Aquinas has a different view. He holds that the higher powers govern the lower in two ways. First, he admits that our rational powers sometimes do follow the lower powers in their judgments, but they need not. A person always chooses whether or not to follow the passions. The source of sin is always the will.[8] A person who sees a wolf might choose to stay and protect his sheep in spite of the fear.

Second, while he admits that all our powers are corrupted by sin,[9] the higher powers broadly inform perception and transform the passions over time. Even if the lower powers do not consult the higher powers in the moment, they are perpetually influenced by them, preparing them for their proper exercise. A cowardly person cannot choose to be brave in the moment of conflict, but he may choose to act brave in spite of his cowardice (since the will always chooses), and he may prepare himself in advance to be brave by testing himself on lesser challenges (over time).  Aquinas analogizes this relationship by saying that the rational powers rule the lower powers politically, not despotically.

Formation as Habit

Formation is about form. Formation implies the capacity to take and hold a new shape. If my golf club is bent into an L shape, it will be disposed to hit bad golf shots. If my memory cannot hold a thought, if I habitually choose things that are bad for me, if my emotions are too easily triggered, then I will be disposed to be a bad human. Habit is the form or shape of our psychological capacities. Habitus is a metaphysically freighted term for Aquinas. We should not think of habit as mindless, repetitive action. Habit is the disposition of our powers to proper function or to dysfunction. Habit perfects a thing to be what it is well.[10] Virtuous habits dispose us to doing good; vicious habits dispose us to doing evil.Habit perfects a thing to be what it is well. Virtuous habits dispose us to doing good; vicious habits dispose us to doing evil. Click To Tweet

The habits required for moral psychology involve the perfection of the rational powers (intellect and will) and the quasi-rational powers (sensitive appetite and apprehension). The cardinal virtues of temperance and fortitude moderate the passions (concupiscible and irascible powers respectively); prudence informs reason; justice regulates the will. When all of these powers are functioning properly, a person can choose well. We will return to this below when we talk about the theological virtues and gifts of the Spirit.

Two people might encounter the same scary situation, say a situation where telling the truth might bring harm, and act in totally different ways. In the first, a habit of courage instilled from his earliest youth might compel him to act with boldness and integrity. In the second, a habit of cowardice might do the opposite. But the presence of a habit makes a difference in how they act with ease and predictability. A cowardly person might choose to take brave action in a given situation, but he will more often and more easily choose cowardice. Habit sits between a power and its act of making the choice, making goodness or wickedness easy and routine.Aquinas offers us a moral psychology that helps us steward our broken bodies for the greater hope that is to come. Click To Tweet

Theological Formulation

So, with all this talk about formation and habit, isn’t this all just Pelagianism? So far in the process I have spoken only of what Aquinas would call acquired virtues and what John Calvin would call civic virtues. These are virtues acquired by practice. As Aristotle writes in Nicomachean Ethics, “we become just by doing just things, temperate by doing temperate things, brave by doing brave things.”[11] Psychologically speaking, we verbally frame our experience through our higher powers, while experience teaches our lower powers. We overcome our fear of spiders both by verbally acknowledging that they are not dangerous, and then by holding them. This relationship between thought and experience is the foundation of cognitive-behavioral therapy.

For both Aquinas and Calvin, acquired virtues are not real virtues because they do not order a person to the knowledge and worship of the Creator. Click To Tweet But, for both Aquinas and for Calvin, the acquired virtues are not real virtues because they do not order a person to the knowledge and worship of the Creator. For a person to be rightly ordered to God the supernatural virtues that come through union with God are necessary. These are faith, hope, and love.

Love has a special role to play, unifying the virtues: “all the moral virtues are infused simultaneously with charity”—rightly aligning the will, which directs all the faculties to “our supernatural end.”[12] Without the theological virtues and the gifts of the Spirit, our habits are splendid vice (to use a term wrongly attributed to Augustine). Every seemingly good action is cut off from its proper doxological end. A person cannot come to God or truly do good apart from the initiating grace of God. Merely human virtues do not commend us to God, even if they contribute to proper human functioning (e.g. health).

Faith, hope, love, and the initiating grace of God

I have tried to sketch out Thomistic moral psychology to highlight its benefits for understanding formation. Chiefly, I am interested in how this holistic and dual process psychology makes sense of formation.For Aquinas and Calvin, a person cannot come to God or truly do good apart from the initiating grace of God. Click To Tweet

His holistic approach to the person avoids dichotomizing body and soul, alerting us to the fact that we face limitations not only from sinfulness, but also from weakness. This is in line with the variety of organic metaphors that the Bible uses for human agency, for growth, and our vital connection to God (e.g., Psalm 1; John 15). His dual process psychology clarifies the relationship between our higher and lower powers and how the higher powers govern the lower providing information and direction to our emotions.

His virtue ethics accounts for how formation happens through habituation of our psychological capacities. We can be well disposed or poorly disposed toward good human functioning, but this takes time. Our habits make doing the right thing easier and more routine. Finally, his virtue ethics are situated within a broader account of human corruption and how God is renewing us by bringing to himself through the work of Jesus Christ. True virtues begin with faith, hope, and love by the initiating grace of God.

So, what difference might this all make for one who is anxious? Matthew 6 suggests that the opposite of anxiety is seeking the kingdom. We might first recognize that anxiety’s origin is complex and bodily involving. Childhood trauma might contribute. The habituation of the amygdala and sympathetic nervous system are a factor. But, the Spirit of God who brought Jesus’ dead body to light, also lives in us, vivifying our bodies (Rom. 8:11). The Spirit of God gives life to us by the renewal of our mind, the participation of our bodies in righteousness and freedom, and through the body of Christ (Rom. 6:11-12; 12:1-21). And even though we in our bodies may still groan awaiting the redemption of our bodies, the Spirit is with us helping us and assuring a good outcome for us (Rom. 8:23-28). True virtues begin with faith, hope, and love by the initiating grace of God, says Aquinas. Click To Tweet

So, we seek and we wait. We participate in kingdom life by living as citizens of that city that is to come. And as our bodies are both being formed and breaking down, we begin to realize that inner strength that does not lose heart as we wait for the “weight of glory beyond all comparison” (2 Cor. 4:16-17). Aquinas offers us a moral psychology that helps us steward our broken bodies for the greater hope that is to come.


[1] Mark D. Jordan “Ideals of Scientia moralis and the Invention of the Summa Theologiae,” in Aquinas’s Moral Theory: Essays in Honor of Norman Kretzmann, ed. Scott MacDonald and Eleonore Stump (Ithaca, NY: Cornell University Press, 1999), 97.

[2] Alexander Pope, “Overview of the Ethics of Thomas Aquinas,” in The Ethics of Aquinas, ed. Alexander Pope (Washington, DC: Georgetown University Press, 2002), 30.

[3] The exception in modern ethics is the moral sense school of which David Hume was a part. Hume’s ethics does highlight character traits and the passions, but doesn’t emphasize their formation.

[4] Thomas Aquinas, Summa Theologica, I.78.1.

[5] Aquinas, Summa, I–II.46.5.

[6] In I–II.40.6, Aquinas says, “young people have high spirits, and so their hearts are bigger. But having a big heart makes one tend toward arduous tasks. And so young people are spirited and full of hope.”

[7] Jonathan Haidt, The Righteous Mind: Why Good People Are Divided by Politics and Religion (New York: Pantheon Books, 2012), 27-94; The Happiness Hypothesis: Finding Modern Truth in Ancient Wisdom (New York: Basic Books, 2006), 1-22.

[8] Aquinas writes, “there are some causes that incline the will to sin in a way that goes beyond the nature and order of the will itself” (I-II.73.6). In this case, there is no sin, because there is no voluntary action.

[9] Aquinas affirms the standard formula from Lombard (also accepted by Calvin), “the natural gifts in man were corrupted, but the supernatural taken away.” Sentences II. Xxv. 8; MPL 192.207

[10] Mere existence is the first act of being (thatness). But the act of inclination in the accidental powers is toward the second act of being, the perfection of being (whatness). Only God’s esse (thatness) is the same as his essence (whatness).

[11] Aristotle, Nicomachean Ethics 2.1, 1103a31-b3.

[12] Aquinas, Summa Theologica, I–II.65.3; I–II.65.2.

Matthew A. LaPine

Matthew LaPine (PhD, Trinity Evangelical Divinity School) is the Christian Education Director at Citylight Omaha. He writes on theology, emotion, and mental health.

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