The Republic by Plato Part 1 Page 84

You are very kind, I said; and would you have the goodness also to inform me, whether you think that a state, or an army, or a band of robbers and thieves, or any other gang of evil-doers could act at all if they injured one another?

No indeed, he said, they could not.

But if they abstained from injuring one another, then they might act together better?

Yes.

And this is because injustice creates divisions and hatreds and fighting, and justice imparts harmony and friendship; is not that true, Thrasymachus?

I agree, he said, because I do not wish to quarrel with you.

How good of you, I said; but I should like to know also whether injustice, having this