“[...]no one can do an injury to you without doing an injury to themselves.”

“For it must be noted, that men must either be caressed or else annihilated; they will revenge themselves for small injuries, but cannot do so for great ones; the injury therefore that we do to a man must be such that we need not fear his vengeance.”

“One who is injured ought not to return the injury, for on no account can it be right to do an injustice; and it is not right to return an injury, or to do evil to any man, however much we have suffered from him.”

“Men ought either to be well treated or crushed, because they can avenge themselves of lighter injuries, of more serious ones they cannot; therefore the injury that is to be done to a man ought to be of such a kind that one does not stand in fear of revenge.”

“The injury we do and the one we suffer are not weighed in the same scales.”

“And let it here be noted that men are either to be kindly treated, or utterly crushed, since they can revenge lighter injuries, but not graver. Wherefore the injury we do to a man should be of a sort to leave no fear of reprisals.”