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Cardinal Virtues as Warrior Virtues

 

Chaplain (Lt. Col.) Jared L. Vineyard, U.S. Army

 

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The job of ethics is not that we may know what virtue is, but that we may become virtuous.

—Aristotle

 

Nearly two centuries ago, Carl von Clausewitz wrote in his seminal work On War, “War is no pastime … it is a serious means to a serious end.”¹ This reality is evident for those who served over the past twenty-plus years in our Nation’s Global War on Terrorism or who currently watch the brutal conflicts in Ukraine or the Middle East unfold. While war is brutal, the character of the warriors that fight them must not be, at least from an American perspective. Instead of brutality, American warriors must uphold serious ends accomplished through serious means. American warriors must do the right thing, for the right reason, in the right way, at the right time. But how does a warrior make the right decision? The purpose of this article is to the answer this vital question. Specifically, this article intends is to propose that the Thomistic formulation of the cardinal virtues ought to be adopted as warrior virtues under the U.S. Army’s current ethical decision-making framework.

An immediate question may arise: What is the U.S. Army’s current ethical decision-making framework? The answer lies in Army Doctrine Publication 6-22, Army Leadership and the Profession. In this document, there is a small section titled “Ethical Reasoning.” In it, after acknowledging that ethical decisions may be demanding, the doctrine states,

Leaders use multiple perspectives to think about ethical concerns, applying them to determine the most ethical choice. One perspective comes from a view that desirable virtues such as courage, justice, and benevolence define ethical outcomes. A second perspective comes from a set of agreed-upon values or rules, such as the Army Values or Constitutional rights. A third perspective bases the consequences of the decision on whatever produces the greatest good for the greatest number as most favorable. Leaders able to consider all perspectives applicable to a particular situation are more likely to be ethically astute.²

Thus, current doctrine suggests three perspectives of how soldiers ought to view, process, and decide when making an ethical decision. While much could be said about the three perspectives at large, the scope of this work is a focused discussion of virtues.

In its current doctrinal formulation, the suggestion to consider virtue is confusing at best and unhelpful at worst. The presence of the word “virtue” in doctrine points to the great Western tradition known as virtue ethics. This tradition stretches back to the time of the ancient Greeks, most notably Plato and his student Aristotle. Doctrine suggests that when an ethical dilemma occurs, an Army professional ought to look through the lens of virtue, along with the other two lenses, to make the right decision. The problem with this suggestion is that doctrine gives no definition or basic understanding of what virtue is nor what virtue ought to be. The only meager assistance is a couple of examples “such as courage, justice, and benevolence.”³ While these examples hint at a holistic solution, they are so cryptic that no Army professional has the time to research their definitions or think about their application.

To help fill in those gaps, others have written proposals to assist leaders in thinking through virtue-based decisions. For instance, the Command and General Staff College currently uses an article by James Svara on the ethical triangle. In the article, Svara suggests that virtue can be simplified to its core idea—integrity—which he also associates with intuition.⁴ In an even older article formerly used by the Command and General Staff College, Dr. Jack Kem suggested that “the Golden Rule can be used to focus the decisions made using this approach: ‘Do to others what you would have them do to you,’” when thinking about virtue ethics.⁵ While both are well-meaning approaches, neither embraces the holistic breadth of what virtue ethics supplies. Therefore, their solutions fall short of true virtue-based decisions, which ought to be part of the ethical decision-making framework.

In Western tradition, there are four cardinal virtues: prudence, justice, fortitude, and temperance. These virtues were embraced by the great philosophic and theological traditions that grounded Western thought and dialogue. For instance, Plato listed and explained the cardinal virtues in Book IV of The Republic, Aristotle had much to say on each of the virtues in Nicomachean Ethics, and Cicero listed the virtues in On Duties.⁶ These Greco-Roman ideals were largely incorporated into medieval and later Western thought by Thomas Aquinas.

Aquinas was a thirteenth-century theologian and philosopher who was a prolific teacher and writer. Among his great works was the unfinished Summa Theologiae, which he desired as a comprehensive account of important topics for those beginning their theological studies. Though never completed, the Summa was a philosophic and theological masterpiece that incorporated much earlier Aristotelian philosophy. Aquinas integrated so much of Aristotle’s work because prior to his time, Aristotle’s writings had been lost to the West. The rediscovery of Aristotle, through Islamic work, was one of the great circumstances that dominated Aquinas’s thirteenth century.⁷ This discovery required a new look at practical matters such as virtue and character. Aquinas and others were confronted with a new “lengthy and sophisticated explanation of how virtue is acquired through moral education, which leads to the cultivation of good habits.”⁸ Consequently, Aquinas melded older Western philosophy with newer theological insights.

This melding and reformulation included part of what would become known as virtue ethics. With regard to virtue ethics generally and ethical decision-making specifically, one might start with Aquinas’s notion of habits in Summa Theologiae.⁹ In it, Aquinas quoted Aristotle, whom he called “the Philosopher,” stating that “the name ‘habit’ is taken from having … [and is] a disposition by which … [one] is disposed … either well or ill … hence it must be said that a habit is a quality.”¹⁰ Regarding dispositions’ relations to habits, Aquinas wrote that a “habit implies disposition relevant to the nature of the thing and to its activity or end, whereby the thing is well disposed thereto.”¹¹ Thus, for Aquinas, a habit is a disposition of the soul in relation to a thing’s nature or activity. He therefore understood that good habits were virtues and bad habits were vices.

A virtue, therefore, is a good habit, but it must be more than a simple inward disposition, it must act. He stated, “Human virtue, which is an operative habit, is a good habit and productive of good works.”¹² Aquinas noted that virtue is both internal and external, that is having the right motivation accompanied by the right actions. Quoting Aristotle again, Aquinas states that “the virtue of a thing is that which makes its work be done well,” and that virtue “implies a certain perfection of power … power in regard to being and power in regard to acting, the perfection of each is called virtue.”¹³ Thus, Aquinas considered that human virtue was an operative habit of the soul producing right ends by right means.

As previously mentioned, Aquinas and many previous philosophic thinkers understood that there were four cardinal virtues, which ultimately formed the foundation for all human virtue. Aquinas quoted Gregory, who stated, “The entire structure of good works is built on four virtues.”¹⁴ Thus, the cardinal virtues act as a fount of all human virtue. All other virtues thus became subsets or associated corollaries to the cardinal virtues, which provided the baseline or ecosystem in which all other virtues and values could thrive. Aquinas believed that they were not only foundational for all virtue but that they ultimately overflowed into each other. Put another way, Aquinas understood the reciprocity of the cardinal virtues.¹⁵ That is, “the cardinal virtues are interconnected in such a way that anyone who truly possesses any of them necessarily possesses all of them.”¹⁶ This meant that for a person to truly attain one of the cardinal virtues, that same individual must achieve all the virtues. One could not simply have one or two of the cardinal virtues; they either attained all of them, or they did not have any of them. With this foundation in place, it is now appropriate to sketch out how Aquinas defined each of the cardinal virtues, using both ancient definitions and newer medieval insights.

Prudence

Aquinas, like those before him, identified prudence as the primal virtue. Prudence, according to the ancients, related to the intellect or the rational part of the soul and was thus focused on reason. Aquinas stated that “prudence is right reason applied to action.”¹⁷ With regard to rightly knowing, prudence dictates that a person “know both the universal principles of reason, and the singulars about which actions are concerned.”¹⁸ That is, prudence was related to both knowing the big picture regarding strategic thinking and understanding specific situations and scenarios in their context. Aquinas, like Aristotle before him, understood that prudence assisted in knowing the golden mean, that is the virtuous center between two character-related extremes. Prudence, as the ancients understood it, was an intellectual virtue that did not have a mean of its own but assisted in finding the mean for other habits or moral virtues. Prudence regulated the mean but did not appoint the end to the moral virtues.¹⁹ It “belongs to prudence rightly to counsel, judge, and command concerning the means of obtaining a due end … not only for private good of the individual, but also the common good of the multitude.”²⁰ Therefore, prudence is a virtue that rightly applies reason to all situations for the goal of human flourishing. Oversimplified, prudence is rational thinking.

Justice

The next cardinal virtue is justice, which relates to the will, according to both ancient and medieval thought. In this vein, Aquinas stated that justice was “a habit by which one wills and does what is just.”²¹ While that may appear self-evident, he went on to specify that justice does not specifically concern itself with oneself but instead “is concerned only about our dealings with others.”²² In these specific dealings with others, Aquinas said that justice “is a habit whereby a man renders to each one his due by a constant and perpetual will.”²³ Thus, on an individual basis, the just person applies reason within the will to act in a right or equitable way toward other people. Aquinas stated that “in one and the same man there is said to be justice in so far as reason commands the irascible and concupiscible, and these obey reason.”²⁴ Therefore prudence, rational thinking, informs the will to do the just act. This action, once executed, is justice. But justice involves more than simple one-on-one relationships, it involves the community as well. This is the difference between commutative and distributive justice. Justice with regard to the community directs toward the common good and ensures that justice “distributes common goods proportionately.”²⁵ Therefore, one might say that justice is a moral virtue that emphasizes right actions toward others, both individually and communally, with regard to equality and proportionality respectively. Justice, oversimplified, is doing right.

Fortitude

The third virtue is fortitude. Fortitude as originally formulated by Aristotle was primarily focused on courage in battle. Aquinas quoted him stating that “fortitude strengthens a man’s mind against the greatest of danger, which is that of death.”²⁶ In discussing battle, Aquinas dealt directly with the idea of just war in his comments on fortitude:

The dangers of death which occur in battle come to man directly on account of some good, because, to wit, he is defending the common good by a just fight. Now a just fight is of two kinds. First, there is the general combat, for instance, of those who fight in battle; secondly, there is the private combat, as when a judge even private individual does not refrain from giving a just judgement through fear of the impending sword, or any other danger though it threaten death. Hence it belongs to fortitude to strengthen the mind against dangers of death, not only such as arise in general battle, but also such as occur in singular combat, which may be called by the general name of battle. Accordingly, it must be granted that fortitude is properly about dangers of death in battle.²⁷

According to Aquinas, battle can and should be just at both the strategic and the tactical levels. Fortitude assisted combatants in this role. But fortitude was more than simply being heroic at both levels; it was “chiefly about fear of difficult things, which can withdraw the will from following reason …. Therefore fortitude is about fear and daring, as curbing fear and moderating daring.”²⁸ In Aquinas’s formulation, prudence informed the will of the right decision to make, and fortitude worked as an encouragement to act correctly with regard to justice. Stated differently, fortitude encourages justice to enact what is prudent. This action relates to both fear and daring that correlated in Aquinas’s mind to the concepts of aggression and endurance. Aggression was the idea of being ready and confident to attack and thus suppressing fear, while endurance was allowing one to see the battle through and thus moderate the desire to be either foolhardy or cowardly.²⁹ One last point to note is that Aquinas agreed with Aristotle that “the habit of fortitude is displayed chiefly in sudden dangers,” because while brave men will consider prudent options ahead of battle, it is the truly courageous soul who chooses the greater good in the face of a deadly unforeseen occurrence.³⁰ Therefore synthesizing Aquinas’s understanding, fortitude is a moral virtue regulating passion toward the obedience to reason with regard to aggression and endurance in the face of danger, planned or spontaneous. To oversimply the definition, fortitude is the right encouragement to do right.

Temperance

The final virtue is temperance. Aquinas believed this as the fourth virtue because while prudence involved all the virtues, and both justice and fortitude directly related to ones relationships with others, temperance “moderates only the desires and pleasures which affect man himself” and therefore affected others only indirectly.³¹ Temperance as a moral virtue “observes the order of reason in all matters and does not exceed its limits.”³² In other words, temperance “withdraws man from things which seduce the appetite from obeying reason.”³³ Thus, temperance is a moral virtue regulating passion toward the obedience of reason with regard to individual pleasure and desire. Again, to oversimplify it, temperance is the right restraint from doing wrong.

As already stated, the cardinal virtues act in conjunction with each other. One must have all the virtues if he or she is to truly have any of the virtues. When viewed holistically, the cardinal virtues could be graphically portrayed as shown in the figure.

According to Western tradition, these virtues act as a foundation for good character and ethical decision-making. If the U.S. Army is to promote the idea of a virtue-based approach to ethical decision-making, the cardinal virtues ought to be the foundation for this instruction.

When proposing a new principle or clarifying an older one, it is appropriate to answer any foreseen arguments against implementation. To do so, this article will address two potential arguments against the cardinal virtues, which include other virtues and the Army Values.³⁴ Regarding the first argument, one might state that the cardinal virtues are cultural and that other virtues could be taught as well. While it is beyond the scope of this article to debate the veracity of universal virtues, it is a good reminder of where U.S. Army doctrine is derived. Our doctrine, and specifically our “Army ethic has its origins in the philosophical heritage, theological and cultural traditions, and the historical legacy that frame our Nation.”³⁵ Simply stated, the Army ethic comes from Western and American traditions and values, which is the exact location of the cardinal virtues. In addition, these virtues are nonsectarian in that they are commended by both ancient pagan and medieval saint alike. While one might argue that other virtues should be considered, it seems difficult to argue that fewer virtues should be.

Another argument might be that the U.S. Army already has the Army Values, so why do we need the cardinal virtues? While the debate of values versus virtues is also beyond the scope of this paper, the response to this critique is twofold. The first is simple—doctrine states that Army professionals ought to consider a virtue-based approach to ethical decision-making, therefore, a defined set of virtues is appropriate. Second, the Army Values by their very nature are not enough when making ethical decisions but are simply part of a larger ecosystem of moral and legal principles that form the Army ethic.³⁶ Therefore, the cardinal virtues would be appropriate to consult in ethical decision-making.

One argument for incorporating cardinal virtues as warrior virtues is prudential. That is, Aquinas’s formulation of the cardinal virtues is simple to learn, easy to remember, and yet holistic when lived out. Simplicity is necessary for warriors on the battlefield due to the complex and ambiguous context that is combat. Quite simply, soldiers train to kill, and while on the battlefield, knowing and applying simple rules of both physical and moral training is not only necessary but lifesaving. Soldiers are taught “to shoot reflexively and instantly” because this is the environment they serve in.³⁷ It has been noted that when soldiers are trained to kill reflexively, their moral autonomy is often undermined, creating the possibility of guilt, negative emotions, or a moral injury from combat situations.³⁸ While this may be true, knowing and training the cardinal virtues when the context is in the simplicity of peace can help a warrior live out the virtues by making ethical decisions when the context is in the complexity of war. As Darrell Cole writes, “The virtuous person is able to act—or better act, react—rightly because such ‘snap decisions’ are a product of will in which the passions are integrated with reason to such a degree that acting ‘passionately’ is in accordance with some good end. Put differently, the virtuous person’s quick reactions are rationally habitual and not instinctual.”³⁹ Simplistic and yet tangible virtue-based training can enhance ethical decision-making for the good of the soldier, unit, and mission.

In addition to the simplicity of the virtues, they are holistic, reflected in their name, cardinal. According to much of Western tradition, they are the foundation for all other virtues. They form the ecosystem in which all other virtues and values can thrive. Their simplicity and yet comprehensive nature are simultaneously demonstrated in this example of a virtue-based warrior code: May your decisions be wise (prudence); may your actions be just (justice); may your manner be courageous (fortitude); and may your desires be restrained (temperance). Warriors trained in a virtue ethic have a greater foundation in moral character and a greater propensity to make ethical decisions.

War is “a serious means to a serious end.”⁴⁰ Thus the warriors who participate in combat must be serious as well. This article has argued that the Thomistic construction of the Western cardinal virtues ought to be adopted as warrior virtues within the current U.S. Army ethical decision-making framework. By specifying and clarifying this perspective, warriors will be both ethically informed and morally aware of the decisions that they are called to make.

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Notes

• Epigraph. This quote is commonly attributed to Aristotle. See, for example, Arthur Herman, The Cave and the Light: Plato versus Aristotle, and the Struggle for the Soul of Western Civilization (Random House, 2014), 54.

1. Carl von Clausewitz, On War, ed. and trans. Michael Howard and Peter Paret (Princeton University Press, 1989), 86.
2. Army Doctrine Publication (ADP) 6-22, Army Leadership and the Profession (U.S. Government Publishing Office, 2019), 2-7.
3. ADP 6-22, Army Leadership and the Profession, 2-7.
4. James Svara, “The Ethical Triangle: Synthesizing the Bases of Administrative Ethics,” Public Integrity Annual (1997): 33–41.
5. Jack Kem, “The Use of the Ethical Triangle in Military Ethical Decision Making,” Public Administration and Management 11, no. 1 (2006): 32.
6. Plato, The Republic, trans. Benjamin Jowett (Fingerprint! Publishing, 6 December 2023); Aristotle, Nicomachean Ethics, trans. Robert C. Bartlett (University of Chicago Press, 23 April 2012); Cicero, On Duties, trans. Benjamin Patrick Newton (Cornell University Press, 2016).
7. Gordon Leff, Medieval Thought: St. Augustine to Ockham (Quadrangle Books, 1959), 169.
8. Peter Adamson, Medieval Philosophy: A History of Philosophy Without Gaps, vol. 4 (Oxford University Press, 2019), 263.
9. Summa Theologiae is divided into three parts. The section focused on moral life and virtues falls into the second part, which is divided into two sections, the Prima Segunda Partis and Secunda Secunda Partis, or simply I-II and II-II, respectively. In I-II, Aquinas writes broadly on the moral life with regard to passions, habits, vices, law, and grace, while in II-II, he focuses primarily on seven virtues, both the theological and cardinal. Each part is broken down into numbered questions, which are further subdivided into numbered articles. The topic of habits is found in part I-II, questions forty-nine through fifty-four.
10. Thomas Aquinas, Treatise on the Virtues, trans. John A. Oesterle (University of Notre Dame Press, 1984), 2–3.
11. Aquinas, Treatise on the Virtues, 9.
12. Aquinas, Treatise on the Virtues, 54.
13. Aquinas, Treatise on the Virtues, 55.
14. Thomas Aquinas, “Article 2. Whether There Are Four Cardinal Virtues?,” Summa Theologiae I-II, New Advent, 25 October 2024, question 61, https://www.newadvent.org/summa/2061.htm.
15. Terence Irwin, The Development of Ethics: A Historical and Critical Study, vol. 1, From Socrates to the Reformation (Oxford University Press, 2011), 543.
16. Jean Porter, “Recent Studies in Aquinas’ Virtue Ethic: A Review Essay,” The Journal of Religious Ethics 26, no. 1 (1998): 203.
17. Aquinas, “Question 47. Prudence, Considered in Itself,” Summa Theologiae II-II, https://www.newadvent.org/summa/3047.htm.
18. Aquinas, “Question 47. Prudence.”
19. Aquinas, “Question 47. Prudence.”
20. Aquinas, “Question 47. Prudence.”
21. Aquinas, Treatise on the Virtues, 19.
22. Aquinas, “ Question 58. Justice,” Summa Theologiae II-II, https://www.newadvent.org/summa/3058.htm.
23. Aquinas, “Question 58. Justice.”
24. Aquinas, “Question 58. Justice.” Irascible means irritable or easily provoked while concupiscible refers to strong desire.
25. Aquinas, “Question 61. The Parts of Justice,” Summa Theologiae II-II, https://www.newadvent.org/summa/3061.htm.
26. Aquinas, “Question 123. Fortitude,” Summa Theologiae II-II, https://www.newadvent.org/summa/3123.htm.
27. Aquinas, “Question 123. Fortitude.”
28. Aquinas, “Question 123. Fortitude.”
29. Aquinas, “Question 128. The Parts of Fortitude,” Summa Theologiae II-II, https://www.newadvent.org/summa/3128.htm.
30. Aquinas, “Question 123. Fortitude.”
31. Aquinas, “Question 141. Temperance,” Summa Theologiae II-II, https://www.newadvent.org/summa/3141.htm.
32. Aquinas, Treatise on the Virtues, 113.
33. Aquinas, “Question 141. Temperance.”
34. “The Army Values,” U.S. Army, accessed 6 May 2025, https://www.army.mil/values/.
35. ADP 6-22, Army Leadership and the Profession, 1-7.
36. For more information on this, see table 1-1, “Foundations of the Army Ethic,” in ADP 6-22, Army Leadership and the Profession, 1-7.
37. Dave Grossman, On Killing: The Psychological Cost of Learning to Kill in War and Society (Back Bay Books, 2009), 256.
38. Peter Kilner, “Military Leaders’ Obligation to Justify Killing in War,” Military Review 82, no. 2 (March-April 2002): 28.
39. Darrell Cole, “Thomas Aquinas on Virtuous Warfare,” Journal of Religious Ethics 27, no. 1 (1999): 61.
40. Clausewitz, On War, 86.

 

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