As long as there is no judge, the injured person takes the matter into his own hands. Canceling the crime is then revenge.

Is revenge just?

In its content, it can be. It pays back what has happened. But in its form, it is the act of a single person. And the injured person is seldom a calm judge. To him, the offense seems to have no limit. He easily pays back too much. Whether his revenge turns out just is a matter of chance.

What follows from this?

For the other, revenge is only a new attack. So he takes revenge in turn. And then the first takes revenge again. So it goes on without end. Two families wage war on each other for generations. No one knows anymore who started it. Revenge passes down from parents to children.

Remnants of it:

Where the state pursues crimes only when the victim complains, a piece of revenge still lives on. So it was in ancient Rome with theft. So it is with some offenses to this day. The injured person decides whether he goes to court.

The revenge of heroes and wandering knights is different. It belongs to the time when states first arise.

Summary: Revenge can be just in its content. But it is the act of an individual and therefore a matter of chance. It breeds new revenge, without end.

§ 500. Such an action is null and void in and for itself as a violation of right. As will and as thinking, the agent sets up in it a law that is, however, formal and recognized only by himself, a universal that holds for him and under which he has, through his action, at the same time subsumed himself. The exhibited nullity of this action — the carrying out, in one, of this formal law and of right in itself, at first through a subjective individual will — is revenge, which, because it proceeds from the interest of immediate, particular personality, is at the same time a new violation, ad infinitum. This progression likewise sublates itself in a third judgment that is without interest, punishment.

§ 500. This action, as a violation of right, is null and void in and for itself, and as will and as thinking, the agent sets up in it a law that is, however, formal and recognized only by himself — a semblance that holds for him — and through it he has at the same time subsumed himself under it. The exhibited nullity of this action — the carrying out of this formal law and at the same time of right in itself, at first through a subjective, individual will — is revenge, which, because it proceeds from the interest of immediate, particular personality, is at the same time only a new violation, ad infinitum. This progression likewise sublates itself in a third judgment that is without interest, punishment.