Lecture 6 — The Mean of Commutative Justice

There remains another kind of justice directive of what is done both in voluntary and involuntary transactions. [947]

This differs in species from the preceding justice. [948]

What is just in the distribution of common goods is always in conformity with proportionality previously discussed, for when distribution is made of common wealth, it will be made according to the proportion contributed by each one. On the other hand, the unjust thing opposed to this just thing is outside the proportional. [949]

However, in transactions, the just thing is an equal—and the unjust thing an unequal—not according to geometrical proportion, but according to arithmetic proportion. Here it does not matter whether the good man steals from the wicked man or the wicked from the good, or whether the good or wicked man commits adultery. The law looks at only the nature of the damage done and treats the parties as equals, if indeed one does an injustice and the other suffers an injustice, if this one injures and that one is injured. Therefore, the judge attempts to reduce to equality the unjust thing that has an inequality. [950]

If one of two contestants receives a wound and the other inflicts a wound, or even if one commits murder and the other is murdered, the division of action and passion brings about inequality. However, a judge tries to remove inequality by awarding damages. [952]

In the interest of plain talk, we speak of gain in these matters, even though the name is not appropriate to some cases, for example, to the person who strikes another or to the person injured. But when passion is measured, one thing is called loss and another gain. [953]

Therefore, that which is just is an equal, a mean between more and less in such a way that gain is taken as more and loss as less. Gain is understood in contrary ways, for it is more in relation to good and less in relation to evil, while the opposite is true of loss. Between gain and loss stands a mean, the equal which we call the just. This, then, is a directive, and will be the mean between gain and loss. [954]

For this reason, when men are in doubt, they have recourse to a judge. But going to a judge is going to justice, for a judge ought to be living justice. Men approaching a judge are seeking an intermediate, and this is why judges are called intermediaries or mediators, as if they touch the mean when they attain what is just. Therefore, the just thing is a mean, as also is the judge who brings about an equality. [955]

947. There remains another kind of justice. After the Philosopher has shown how the mean should be taken in distributive justice, he now explains in what way the mean should be understood in commutative justice. He discusses this point under three aspects.

First, he shows there is a species of justice in addition to distributive.

Second, at this differs (1131b26; [948]), he says this differs from the other justice.

Third, at it is as though (1132a25; [956]), he shows how a mean should be understood in this kind of justice.

He says first that, in addition to the preceding species of justice which exists in distributions, there remains one that is directive of transactions both voluntary and involuntary.

948. Then, at this differs (1131b26), he shows the difference between this species and the preceding.

He treats this point under two headings.

First, he sets forth his proposition, saying that the just thing existing in transactions belongs to a species other than distributive justice.

949. Second, at what is just (1131b27), he presents the difference.

First, he reviews something relevant to distributive justice.

Second, at however, in transactions (1131b32; [950]), he shows what pertains to commutative justice.

He says first that the justice mentioned before always directs the distribution of common goods in conformity with proportionality, that is, the geometrical, which is observed in the equality of proportion. This is clear because, if wealth belonging to the city or to certain men must be distributed to individuals, the distribution will be made in such a way that each may receive from the community in that ratio according to which he contributed to the community. We suppose in business ventures that the more a man invests in a company, the greater is his return. As the just thing directing distributions consists in this proportionality, so the opposite unjust thing consists in disregarding proportionality of this kind.

950. At however, in transactions (1131b32), he shows what pertains to commutative justice.

He gives a threefold consideration of this notion.

First, he explains a fact relative to commutative justice.

Second, at if one of two contestants (1132a7; [952]), he clarifies this by an example.

Third, at therefore, that which (1132a14; [954]), he deduces some corollaries from the premises.

He says first that the just thing that exists in transactions agrees somewhat with the just thing directing distributions in this—that the just thing is equal and the unjust thing is unequal. But they differ in the fact that the equal in commutative justice is not observed according to that proportionality observed in distributive justice—namely, geometrical—but rather according to arithmetical proportionality, which is observed according to equality of quantity and not according to equality of proportion, as in geometry. By arithmetical proportionality, six is a mean between eight and four, because it is in excess of the one and exceeds the other by two. But there is not the same proportion on the one side and the other, for six is to four in a ratio of three to two while eight is to six in a ratio of four to three. On the contrary, by geometrical proportionality, the mean is exceeded and exceeds according to the same proportion, but not according to the same quantity. In this way, six is a mean between nine and four, since from both sides there is a three to two ratio. But there is not the same quantity, for nine exceeds six by three and six exceeds four by two.

951. Therefore, in commutative justice, the equal is observed according to arithmetic proportion. This is clear from the fact that, here, the different relations of persons are not considered. It does not matter, insofar as commutative justice is concerned, whether a good man has stolen or robbed an evil man of his property or an evil man has done it to a good citizen. Likewise, it does not matter whether a good or evil man commits adultery. The law takes into account only the nature of the injury, such that the man who has done more damage, whatever his condition, must make more restitution. So it is evident that, if one of two contestants does an injustice and the other suffers an injustice, one injures and the other is injured, the law treats them as equals, however much they may be unequal. Hence, a judge, who is a dispenser of the law, attempts to reduce that injustice—by which one man injures another and that has a certain inequality—to an equality by establishing an equality in the very quantity of things and not according to the relation of different persons.

952. Next, at if one of two contestants (1132a7), he clarifies what he had said, by an example.

First, he presents the example;

second, at in the interest of plain talk (1132a10; [953]), he resolves a doubt.

First, he sets forth the example of a personal injury about which too little is clear. He says that if one of two contestants receives a wound and the other inflicts it, or even if one commits murder and the other is murdered, this division of action and passion brings about inequality, because the assailant and the murderer have more of what is esteemed good, inasmuch as they have done their own will and so seem to have gained. But the man who is wounded or murdered has more of evil insofar as he is deprived against his will of well-being or life, and so he seems to have suffered loss. The judge tries to equalize this by subtracting from the gain and allotting compensation for the loss, inasmuch as he takes away something from the assailant and the murderer contrary to their will and bestows it to the gain or honor of the person wounded or murdered.

953. Then, at in the interest of plain talk (1132a10), he resolves a certain doubt that could arise from the words “gain” and “loss.” He says that, in the interest of plain talk, the terms “gain” and “loss” are used in matters where a person has more or less. Strictly, these words refer to what we possess, and sometimes they do not seem suitable, such as in the case of personal injuries (as when one person receives a blow and another inflicts it, some injury results), because a fixed measure of action and passion cannot be taken in injuries of this kind such that what is more can be called gain and what is less, loss. But when passion is measured, that is, according to the measure of justice, then what is more is called gain and what is less, loss.

954. At therefore, that which is just (1132a14), he deduces two conclusions:

the first, on the part of the just thing itself;

the second, at for this reason (1132a19; [955]), on the part of the judge.

He says first that the just thing in transactions is a kind of equal that is a mean between more and less in such a way that gain is taken as more and loss as less. However, they are understood in different ways in good and evil, for to have more of good and less of evil belongs to the nature of gain. But the contrary pertains to the idea of loss. Between these two, gain and loss, stands a mean, that equal that we call the just thing. Consequently, that just thing that gives directions in transactions is a mean between gain and loss as these terms are commonly understood.

955. Next, at for this reason (1132a19), he draws a conclusion on the part of the judge of whom it was said [952] that he tries to bring about an equality. Aristotle affirms that, because the just thing is a mean between gain and loss, it follows that, when men are in doubt about the mean, they have recourse to a judge. A judge ought to be, as it were, living justice, such that his soul is entirely possessed by justice. But the people who go to a judge seem to be seeking a mediator between parties who quarrel. Consequently, judges are called “intermediaries” or “mediators,” as if they may attain the intermediate or the mean and lead the way to what is just. So, then, it is evident that what is just—the subject of our discussion—is a certain mean, because the judge, who determines this just thing, is the middle inasmuch as he proposes what is equal between the parties. But the equal is the mean or middle between more and less, as we have pointed out [310, 933].