Nicomachean Ethics, Aristotle [most read books of all time .txt] 📗

more than your own is called gaining, and having less than you started with is called losing (in buying and selling, I mean, and in the other transactions in which the law allows free play); but when the result to each is neither more nor less but the very same amount with which he started, then they say that they have their own, and are neither losers nor gainers. That which is just, then, is a mean between a gain and a loss, which are both contrary to the intention,108 and consists in having after the transaction the equivalent of that which you had before it. V

Some people, indeed, go so far as to think that simple requital is just. And so the Pythagoreans used to teach; for their definition of what is just was simply that what a man has done to another should be done to him.

But this simple requital does not correspond either with that which is just in distribution or with that which is just in the way of redress (though they try to make out that this is the meaning of the Rhadamanthine rule⁠—“To suffer that which thou hast done is just”); for in many cases it is quite different. For instance, if an officer strike a man, he ought not to be struck in return; and if a man strike an officer, he ought not merely to be struck, but to be punished.

Further, it makes a great difference whether what was done to the other was done with his consent or against it.

But it is true that, in the interchange of services, this is the rule of justice that holds society together, viz. requital⁠—but proportionate requital, and not simple repayment of equals for equals. For the very existence of a state depends upon proportionate return. If men have suffered evil, they seek to return it; if not, if they cannot requite an injury, we count their condition slavish. And again, if men have received good, they seek to repay it: for otherwise there is no exchange of services; but it is by this exchange that we are bound together in society.

This is the reason why we set up a temple of the graces [charities, χάριτες] in sight of all men, to remind them to repay that which they receive; for this is the special characteristic of charity or grace. We ought to return the good offices of those who have been gracious to us, and then again to take the lead in good offices towards them.

But proportionate interchange is brought about by “cross conjunction.”

For instance, let A stand for a builder, B for a shoemaker, C for a house, D for shoes.109

The builder then must take some of the shoemaker’s work, and give him his own work in exchange.

Now, the desired result will be brought about if requital take place after proportionate equality has first been established.110

If this be not done, there is no equality, and intercourse becomes impossible; for there is no reason why the work of the one should not be worth more than the work of the other. Their work, then, must be brought to an equality [or appraised by a common standard of value].

This is no less true of the other arts and professions [than of building and shoemaking]; for they could not exist if that which the patient [client or consumer] receives did not correspond in quantity and quality with that which the agent [artist or producer] does or produces.111

For it is not between two physicians that exchange of services takes place, but between a physician and a husbandman, and generally between persons of different professions and of unequal worth; these unequal persons, then, have to be reduced to equality [or measured by a common standard].112

All things or services, then, which are to be exchanged must be in some way reducible to a common measure.

For this purpose money was invented, and serves as a medium of exchange; for by it we can measure everything, and so can measure the superiority and inferiority of different kinds of work⁠—the number of shoes, for instance, that is equivalent to a house or to a certain quantity of food.

What is needed then is that so many shoes shall bear to a house (or a measure of corn) the same ratio that a builder [or a husbandman] bears to a shoemaker.113 For unless this adjustment be effected, no dealing or exchange of services can take place; and it cannot be effected unless the things to be exchanged can be in some way made equal.

We want, therefore, some one common measure of value, as we said before.

This measure is, in fact, the need for each other’s services which holds the members of a society together; for if men had no needs, or no common needs, there would either be no exchange, or a different sort of exchange from that which we know.

But money has been introduced by convention as a kind of substitute for need or demand; and this is why we call it νόμισμα, because its value is derived, not from nature, but from law (νόμος), and can be altered or abolished at will.

Requital then will take place after the wares have been so equated [by the adjustment of prices] that the quantity of shoemaker’s work bears to the quantity of husbandman’s work [which exchanges for it] the same ratio that husbandman bears to shoemaker,114 But this adjustment must be made,115 not at the time of exchange (for then one of the two parties would get both the advantages116), but while they are still in possession of their own wares; if this be done, they are put on an equal footing and can make an exchange, because this kind of equality can be established between them.

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