History of the Peloponnesian War

It was in Corcyra then that most of these things were first ventured on; both the deeds which men who were governed with a spirit of insolence, rather than of moderation, by those who afterwards afforded them an opportunity of vengeance, would do as the retaliating party; or which those who wished to rid themselves of their accustomed poverty, and passionately desired the possession of their neighbours' goods, might unjustly resolve on; or which those who had begin the struggle, not from covetousness, but on a more equal fooling, might savagely and ruthlessly proceed to, chiefly through being carried away by the rudeness of their anger.

Thus the course of life being at that time thrown into confusion in the city, human nature, which is wont to do wrong even in spite of the laws, having then got the mastery of the law, gladly showed itself to be unrestrained in passion, above reward for justice, and an enemy to all superiority. They would not else have preferred vengeance to region, and gain to innocence; in which state envy would have had no power to hurt them.

And so men presume in their acts of vengeance to be the first to violate those common laws on such questions, from which all have a hope secured to them of being themselves rescued from misfortune; and they will not allow them to remain, in case of any one's ever being in danger and in need of some of them.