It is easy to read Book 5 of Aristotle’s Nicomachean Ethics as a technical treatise on “justice.” We can easily fixate on “general justice” vs “particular justice” or “distributive justice” vs “corrective justice,” but to do so is to set aside how this book resolves some loose ends in the earlier books while setting up the powerful and enduring discussions of phronesis (as a form of correct reason) and friendship (two full books on this virtue) as the foundation of a just society.

A richer engagement with Book 5 leads us to see how Aristotle makes a crucial turn from virtue as “individual perfection” to virtue as how one is disposed to treat others. The problem is how to extend virtuous action from the individual to the community and back again. “Justice” is the term that Aristotle uses to make this extension. As such, justice is the orientation of one’s virtuous actions to the benefit of others and it is the perfection of virtue — its telos. This is what makes justice so difficult — it demands that we look beyond ourselves as isolated individuals and to see our perfection arising from our membership in a community.

Worst, then, is he who treats both himself and his friends in a corrupt way, but best is he who makes use of virtue not in relation to himself but in relation to another. For this is a difficult task. This justice, then, is not a part of virtue but the whole of virtue, and the injustice opposed to it is not a part of vice but the whole of vice. In what respect virtue and this justice differ is clear from what has been said. For they are the same, though in their being, they are not the same; rather, in the respect in which it bears a relation to another, it is justice; in the respect in which it is simply a characteristic of this sort, it is virtue. (5.1 1130a7-14, emphasis added)

By the time we get to the end of Book 5, this ability to look beyond ourselves and make personal sacrifices for the well-being of others will be justice as “equity” — the disposition/characteristic (hexis) to moderate one’s own natural greed for the sake of others. This ethical disposition will be the very ground on which a just society is founded and the law alone will be shown to be insufficient to guarantee justice. But let’s not get ahead of ourselves. I’ll come back to this later.

At the heart of Book 5 is a vision of human community that must actively grapple with two issues that endure in our discussions of justice, virtue and human happiness to this day:

• How to deal with innate human needs that we cannot fulfill without joining together with others — not everyone can be a doctor, farmer, and shoemaker simultaneously. We need help from others to fulfill these basic needs let alone live a happy life.

• How to deal with the human tendency to strive to get more of the good things and less of the bad things for oneself. This is not a separate problem from the formation of human communities as fulfilling needs and as the best means to a happy life. It is a problem that arises as soon as humans come together to fulfill each others needs and desires through exchange and money.

This tension drives the rest of NE. Human beings must live together and form laws (and obey them), but there is nothing in that tendency that guarantees that they will be happy together, pursue justice together, or be better off than living alone.

For Aristotle, the law (nomos, which could also be custom and conventions) is central to this discussion because of its problematic ability to reconcile these problems of human need (which brings us together) and greed (which drives animosity and sows discord if not handled properly). Nomos is central because it is the “art of legislation” that is supposed to create virtuous citizens, but there is no guarantee that nomos is aligned with virtue; it may be aligned in a given polis, but “only incidentally” (1137a12).

Therefore, the law does not, by itself, guarantee a just society for Aristotle. But that does not make it irrelevant either. Rather, the law bears the burden of both creating virtuous citizens but also being the creation of virtuous citizens (see 2.1 1103b). Again, we find Aristotle engaging in circular logic — which is no vice as I’ve covered in a previous meditation. This is because virtue is circular by its very nature — the virtues come into existence and are perfected by being put into action. The more one acts virtuously, the more one creates the characteristics and dispositions to act virtuously over the course of a lifetime.

At the level of one’s individual self, the circularity of virtue is encompassed by the words “characteristics” (hexis) and “dispositions.” At the level of one’s relationship to others, this circularity is “justice.” To be a virtuous society is to be a just society, but to be a just society requires that the citizens be habituated and disposed to be virtuous. Circularity once again.

The law for Aristotle is not the fundamental ground on which justice and human happiness resides, though it is necessary. It is not, as Plato might have it, an expression and application of universal principles. Aristotle can’t go there because he sees the fundamental tensions of human society as “particular” and cannot be reduced to general principles. We saw this in his critique of Plato’s eidos-driven concept of “the good” in 1.6 and 1.7. In that argument, Aristotle was concerned with treating “the good” as practical outcomes rather than an originating idea that erases the differences between a well-made house and the work of a doctor. For Aristotle, reducing these different goods to a singular unifying idea is simply impractical for making decisions about how to live together.

In Book 5, Aristotle pushes this problem of universals and particulars even further. While the art of legislation must deal in universals, it cannot know or predict all of the particular situations in which the universal will be applied. Human life — struggling between satisfying needs and the propensity to get more than one’s fair share of the good things — is too messy for universal principles to be so easily applied.

But Aristotle pushes further. In 5.10, he does not leave the problem of universals and particulars at simply an argument about the impracticality of universals. He explicitly tells us that the application of universals can create the very problems it seeks to resolve in the first place. If we rely solely on a concept of justice that means obeying the laws, we’ll find ourselves ill equipped to deal with the particular problems that arise in the balancing of needs and the desire for gain. This is because laws as written down necessarily deal with generalities, but life is lived in the particulars, especially when it comes to distribution of social goods (honor, wealth) and the correction of imbalances in the distribution.

But laws are meant to apply general rules to particular situations. That is the nature of how laws work. Aristotle recognizes this and provides us with a resolution that feels strikingly modern. The very application of universal principles to particular situations will lead naturally and inevitably to error. This is the “perplexity” that Aristotle dwells on in 5.10: the application will be wrong and a correction will have to be made to make the particular situation just. This is where “equity” comes into play as a social virtue that corrects the outcomes that necessarily occur when generalities are applied to particular situations:

Therefore, the just and the equitable are the same thing, and although both are serious, the equitable is superior. This is what produces the perplexity, because although the equitable is just, it is not what is just according to law. The equitable is instead a correction of the legally just. The cause of this is that all law is general, but concerning some matters it is not possible to speak correctly in a general way. In those cases, then, in which it is necessary to speak generally, but it is not possible to do so correctly, the law takes what is for the most part the case, but without being ignorant of the error involved in so doing…

Hence equity is just and better than what is just in a certain sense [according to law] — not what is just unqualifiedly [i.e., without respect to a particular situation] but the error that arises through its being stated unqualifiedly [i.e., as generalized rules]. This is in fact the nature of the equitable: a correction of law in the respect in which it is deficient because of its being general. (5.10 1137b10-28, emphasis added)

This is different than the “corrective justice” that many commentaries on NE’s concept of justice fixate on. “Corrective justice” in the final sections of Book 5 is necessary not only because people do bad things — they grab more of the good and less of the bad for themselves — but because the very application of the law (as general principle to particular situations) will create errors that need to be corrected.

The law cannot correct itself. It needs help from virtuous citizens who are disposed to treating each other fairly and equitably. Equity is the perfection of justice — its telos — because it is the dispostion/characteristic that respects the particulars of any given situation and seeks the fair outcomes. In other words, how need and greed will play out in any given circumstance cannot be adjudicated ahead of time, but must be judged, managed and reconciled in the moment. General laws are necessary but insufficient to creating fair outcomes.

Book 6 on phronesis, or practical reason, is a natural and logical extension of where Aristotle is taking us in Book 5’s discussion of justice. The politician (and by extension the virtuous citizen) cannot simply be “wise,” he must be “disposed” to doing the right thing, which means being habituated and developing the virtuous characteristics to judge a given situation on its own merits and make the right choices:

What the equitable is, then — that it is both just and better than the just in a certain sense — is clear. It is manifest from this also who the equitable person is: he who is disposed to choose and to do these sorts of things and is not exacting to a fault about justice, but is instead disposed to take less for himself even though he has the law on his side, is equitable. And this characteristic is equity, it being a certain sort of justice and not some other characteristic. (1137b33-1138a2)

Equity is thus a form of justice that is not strictly legal or codified in law. It stretches the law to the breaking point for Aristotle and centers the problem of society on the ethical interactions between individual citizens.

Conflicts and errors of justice are not accidental or abnormal. They are what happens when human beings get together to satisfy their needs. These issues also never end. Society never reaches a perfect state. It must go on negotiating these conflicts because that’s what society is. Thus morality in the form of a practical ability to negotiate equity is essential to a just society.