Few terms have assumed more prominence in public discourse, especially that emanating from the left, in recent decades than “social justice.” It has now become part of the rhetorical apparatus of virtually all center-left, social democratic and labor political movements as well as central to the language of modern liberalism. In Western Europe, the term has also been embraced by more-than-a-few center-right, Christian Democrat, and conservative groupings, David Cameron’s Tory Party being a prominent example. Religious groups—most notably, but not exclusively, the Catholic Church—also utilize the expression extensively in their commentary on social and economic subjects. In the case of many mainline Protestant confessions, it seems to have become their defining creed.
A common criticism from the non-left is that social justice appears to have no stable or concrete meaning. This point features prominently in the critique articulated by Friedrich Hayek in The Mirage of Social Justice, in the second volume of his Law, Legislation and Liberty. Hayek struggled, he wrote, to find a clear definition of what people mean by the term. To the extent that social justice operates as a catch-all justification for any number of programs that range from extensive income redistribution and anti-discrimination policies, there is little doubt the phrase is used in a bewildering number of often contradictory and not especially coherent ways.
This brief essay does not to enter into these discussions. Nor does it provide a new definition of the term or consider its salience in contemporary policy debates and public discourse. Rather my purpose is to engage in the significantly more limited task of locating the meaning of social justice in the classical tradition of natural law reasoning, with particular reference to Roman Catholic pronouncements about this subject. I hope to demonstrate that social justice in this tradition amounts to the equivalent of what Thomas Aquinas called “general justice:” that is to say, social justice is about the common good—a term which itself also has very particular meaning in this tradition of reasoning.
Justice as a Virtue, Justice and the Common Good
Natural law ethics has identified justice as one of the cardinal virtues ever since Aristotle commenced his treatment of justice with the general notion of “legal justice” (the terms “legal” and “general” being more-or-less interchangeable). By this, he meant comprehensive virtue with regard to relationships with other persons. Justice-as-a-virtue was henceforth understood in this tradition as having a uniquely social dimension in the sense that one of its key elements is other-directedness.
As a virtue, general justice properly understood involves one’s general willingness to promote the common good of the communities to which one belongs. Here the common good should be understood as the conditions that promote the all-round integral flourishing of individuals and communities. Another element of justice which presents itself very early in the tradition is that of duty in the sense of what we owe to others. This is closely associated with a third element: equality. This should not be understood in the sense of everyone somehow being entitled to precisely the same, regardless of factors such as need or merit. Instead it means fairness as expressed in the Golden Rule. Injustice can after all involve doing things to people that entail no violation of any prior undertaking. Robbing someone, for instance, involves no breaking of any freely-entered-into agreement with the person from whom I steal. But does anyone doubt that an injustice has been done?
These three elements—other-directedness, duty (or what might be called rights today), and the Golden Rule—are closely linked and substantially overlap with each other. But attention to all three elements underscores that the same common good which is the end of general justice requires more than simply a broad inclination on the part of individuals and groups to promote the flourishing of others and themselves. On one level, as Aquinas specifies, it is a special concern of the rulers since they have a certain responsibility to promote the common good. But Aquinas also notes that it is a concern of every citizen: that is, those who participate in some way with the ruling of the community.
There is also the question of general justice’s tangible requirements vis-à-vis persons. This is often called “particular justice.” Aquinas defined particular justice in the following manner and explained how it produced two species of justice:
particular justice is directed to the private individual, who is compared to the community as a part to the whole. Now a twofold order may be considered in relation to a part. On the first place there is the order of one part to another, to which corresponds the order of one private individual to another. This order is directed by commutative justice, which is concerned about the mutual dealings between two persons. On the second place there is the order of the whole towards the parts, to which corresponds the order of that which belongs to the community in relation to each single person. This order is directed by distributive justice, which distributes common goods proportionately. Hence there are two species of justice, distributive and commutative.
From this standpoint, these two species of justice concern the just resolution of certain coordination problems concerning (1) the relationship between individuals and communities when it comes to the distribution of common resources in a just manner (according to criteria such as merit, desert, function and need); and (2) relations between individuals and groups engaged in particular exchanges. In the case of distributive justice, there has been considerable attention to its meaning for property-arrangements. Commutative justice has been understood as especially applicable to questions such as contract and the adjudication of disputes arising from such relationships. In both cases, the state assumes responsibility for coordinating these modes of justice. It provides, for instance, an overall framework that governs the ownership and use of property, and establishes and presides over the arrangements for adjudicating and resolving disputes.
Confusing Modes of Justice
The question of the stability of all these terms—legal/general justice, particular justice, commutative justice, distributive justice—vis-à-vis each other has always been the cause of considerable debate, development and revision within the classical natural law tradition. The distinction between general and particular justice, for instance, can be somewhat obscure. As John Finnis notes, when Aquinas refers to promoting the well-being of the individuals in a group, he believes that in doing so one is also acting for the good of that group. Likewise consideration of what commutative justice demands in seeking to determine what two or more people owe each other in a set of mutually agreed-upon arrangements, often involves reflection upon the criteria associated with distributive justice. This is a regular occurrence in bankruptcy law. Courts charged with determining what individuals and/or groups owe each other end up employing criteria of distributive justice such as merit, dessert, need, and function in deciding who gets what from whatever is left of a set of common resources upon which there are competing claims.
In Aquinas’s thought, all these modes of justice appear to flow from legal/general justice insofar as they are all derived from everyone’s responsibility to the common good. It is arguable, however, that efforts to lend stability to these different “parts” of justice caused, over the long term, the tradition to lose sight of this point. This is apparent in the attempt by neo-scholastic thinkers such as Cardinal Cajetan and Dominic Soto to clarify the relationship between general, commutative and distributive justice. Cajetan, for instance, specified that:
There are three species of justice, as there are three types of relationship between any “whole:” the relations of the parts among themselves, the relation of the whole to the parts, and the relations of the part to the whole. And likewise there are three justices: legal, distributive and commutative. For legal justice orientates the parts to the whole, distributive the whole to the parts while commutative orients the parts one to another.
Notice how Cajetan essentially places general, distributive, and commutative justice on the same plane. In his schema, general justice is not the foundation of the other modes of justice. The effect of this was to gradually separate commutative and distributive justice from the demands of general justice. This resulted in a narrowing of the scope of something like commutative justice. This came to be seen as strictly limited to dealings between two or more private parties and somehow shielded from the demands of the common good to which general justice points. Likewise, distributive justice came to be defined in terms of relationship between the individual and the state. One finds this schema of justice outlined, for example, in influential mid-twentieth century books such as Johannes Messner’s tome on social and economic ethics as well as Heinrich Rommen’s The Natural Law.
Why “Social Justice”?
As demonstrated in a series of articles written in the 1960s by the French Dominican Paul Dominique Dognin, the term social justice was employed in Catholic social teaching in the 1930s to restore general justice to its central place in the tradition’s treatment of justice. Though the phrase was used as early as the 1830s by Thomist scholars, Pope Pius XI provided it with particularly concrete definition in his 1937 encyclical condemning Communism, Divini Redemptoris:
In reality, besides commutative justice, there is also social justice with its own set obligations, from which neither employers nor workingmen can escape. Now it is of the very essence of social justice to demand for each individual all that is necessary for the common good. But just as in the living organism it is impossible to provide for the good of the whole unless each single part and each individual member is given what it needs for the exercise of its proper functions, so it is impossible to care for the social organism and the good of society as a unit unless each single part and each individual member—that is to say, each individual man in the dignity of his human personality—is supplied with all that is necessary for the exercise of his social functions.
The context of these remarks is a discussion of the relationship between employers and employees. They underscore how both groups must go beyond an excessively narrow conception of commutative justice when thinking about what justice requires. Instead they must take into account conditions “outside” this particular relationship that affect the human flourishing more generally of the wider community. The reference to the common good serves to specify this as the end of social justice, thereby reestablishing general justice as foundational to natural law reasoning about these matters.
Social Justice, Subsidiarity and Freedom
Since the time of Pius XI, this linkage of social justice with the common good has been made in a number of official Catholic teachings, though not always, it may be said, with great precision. Such criticism cannot, however, be made of the Catechism of the Catholic Church. “Society,” it states, “ensures social justice when it provides the conditions that allow associations or individuals to obtain what is their due, according to their nature and their vocation. Social justice is linked to the common good and the exercise of authority.”
Here social justice is clearly concerned with describing our obligations to the common good, with the emphasis being upon people receiving what they are owed. Obviously the state has a role in this—hence the reference to authority. Equally significant, however, is the emphasis upon society pursuing this end. It follows that social justice is not and cannot be the government’s exclusive concern. The common good is everyone’s concern. Hence, not every or even most actions that seek to contribute to its realization should necessarily come from the state.
This last point becomes more explicit in the paragraphs in the Catechism immediately following this definition. In the first place, the Catechism states, social justice involves respect for human rights that society recognizes rather than creates. This echoes the tradition’s early attention to the duties that people owe each other. Second, the Catechism stresses that social justice underscores the basic equality of all people that is theirs by virtue of being made in God’s image: i.e., their sharing in the same dignus that makes all humans superior to all other animal and plant life but also equal to each other by virtue of sharing in the same human substance.
Third—and in a move that may surprise some—the Catechism specifies that pursuing social justice requires us to acknowledge the differences and even inequalities that are legitimate and even necessary in any society. Many of these differences exist, the Catechism states, because God wills that we need each other. Such variations enable us to use our disparate talents and resources to meet others’ needs and thereby contribute to the common good in different and often compatible ways. Lastly the Catechism states that social justice embraces the idea of “solidarity.” Revealingly, the Catechism emphasizes that solidarity cannot be reduced to a single-minded focus on material goods. Rather it involves “the sharing of spiritual goods even more than material ones.” Human flourishing is more than just material well-being. The “goods” in question are those values that make us truly human and thus different from every other species.
This reference to solidarity especially matters because it harkens back to an important point made by the meaning of solidarity (another word used rather indiscriminately in the realm of politics) by the late John Paul II. John Paul II employed the word “solidarity” to describe a person’s chosen commitment to the good of others as a specific moral attitude and virtue. More specifically “it is a firm and persevering determination to commit oneself to the common good; that is to say to the good of all and each individual, because we are all really responsible for all.” Solidarity thus finds its ultimate end not in some earthly Rousseauian utopia of universal brotherhood. Instead it is expressed through the virtue of promoting the conditions that facilitate human flourishing.
The word “virtue” implies that solidarity needs to become as much a moral habit as something like courage or temperance. It also takes us full-circle back to the idea of justice as a virtue. Virtues, moreover, are only realized when a person freely commits himself to acting consistently for the good. Thus John Paul stressed that “an essential condition” for living out the virtue of solidarity “is autonomy and free self-determination.” To realize solidarity as a good thus means that, at some level, I must decide freely to commit myself to my neighbor and to the common good—and I must do so continuously.
This does not mean that the state and law has no role whatsoever in encouraging people to embrace the goods that lie at the heart of human flourishing—including the virtue of solidarity. Such a position cannot be reconciled with either classical natural law reasoning or Catholic social ethics. The question, however, is how we build a concern for liberty and human flourishing into the way that all institutions and communities help to promote solidarity/the common good/social justice in a given society. To this extent, subsidiarity reminds us of the ultimate end of social justice: the good of each and every person.
At this point, we begin to see how solidarity relates to the principle of subsidiarity. Aquinas himself insisted that, with the exception of particular emergencies, justice itself requires that individuals in a community be free to carry out their duties and obligations via their own free choices and actions. Because subsidarity is not just about limiting state power. If we are to flourish under our own volition, we need to do things for ourselves—as the fruit of our own reflection, free choices, and acts—rather than have others (including the state) do those things for us that we are indeed capable of doing.
None of the preceding commentary should be understood as suggesting that we necessarily need to rescue the expression “social justice” from those who characteristically associate it with any number of causes customarily identified as “left-wing” or “progressive.” For many such individuals and groups, social justice seems to be equated with efforts to realize ever-greater sameness of starting point and/or end-point—something that, as illustrated, is quite foreign to the classical natural law’s understanding of equality. Many of the same individuals and groups seem quite disinterested in and/or hostile to the substantive or thick accounts of human flourishing which are central to natural law reasoning about social justice and the common good.
That said, it is worth asking those who regularly employ the term social justice how much they recognize their own thinking and presuppositions in the foregoing commentary. My suspicion is that in many if not most cases (including a number of Christians), the honest answer would be “very little.” At the same time, one hopes that many of those who criticize the use of expressions like social justice will consider that, at least in some traditions, the concept is not as empty as they may have hitherto supposed.
 See Aristotle, Nicomachean Ethics (Indianapolis, IN: Hackett Publishing Company, 1999), V.1: 1129b26-1130a13.
 See Thomas Aquinas, Summa Theologiae (London: Blackfriars, 1963), II-II, q. 58, a.6c.
 ST, II-II, q. 61, a.1
 See John Finnis, Aquinas: Moral, Political and Legal Theory (Oxford: OUP, 1998), p. 217.
 Thomas de Vio, Cardinal Cajetan, Commentaria in Secundum Secundae Divi Thomae ad Aquino (1518), cited in John Finnis, Natural Law and Natural Rights (Oxford: Clarendon Press, 1980), p. 185.
 See Johannes Messner, Social Ethics: Natural Law in the Modern World (St. Louis, Mo.: B. Herder Book Co., 1949), p. 218; Heinrich Rommen, The Natural Law (Indianapolis: Liberty Fund  1998, p. 67; and Josef Pieper, Justice (New York: Pantheon Books, 1955), p. 125.
 See, for example, Paul-Dominique Dognin, O.P., “La notion thomiste de justice face aux exigences modernes,” Revue des Sciences Philosophiques et Théologiques 45 (1961), pp. 601-40.
 Pius XI, Encyclical Letter Divini Redemptoris (1937), para. 55. http://www.vatican.va/holy_father/pius_xi/encyclicals/documents/hf_p-xi_enc_19031937_divini-redemptoris_en.html
 Catechism of the Catholic Church (1993), para. 1928. http://www.vatican.va/archive/ENG0015/_INDEX.HTM
 CCC para. 1928-1948.
 See Elizabeth Anscombe, “The Dignity of the Human Being,” in Mary Geach and Luke Gormally (eds.), Human Life, Action and Ethics: Essays by G.E.M. Anscombe (Exeter: Imprint Academic, 2005), pp. 67-76.
 CCC para. 1948.
 John Paul II, Encyclical Letter Sollicitudo Rei Socialis (1987) para. 38. http://www.vatican.va/holy_father/john_paul_ii/encyclicals/documents/hf_jp-ii_enc_30121987_sollicitudo-rei-socialis_en.html
 SRS para. 45.
 See Thomas Aquinas, Summa contra Gentiles (Notre Dame, IN.: University of Notre Dame Press, 1975), III, c. 71, n.4.