The notion that men lived originally in a state of nature, by violence and without laws, is due to Critias. Communism in its grossest form was recommended by Diogenes of Sinope. According to the Sophists, there is no duty above expediency and no virtue apart from pleasure. Laws are an invention of weak men to rob their betters of the reasonable enjoyment of their superiority. It is better to inflict than to suffer wrong; and as there is no greater good than to do evil without fear of retribution, so there is no worse evil than to suffer without the consolation of revenge. Justice is the mask of a craven spirit; injustice is worldly wisdom; and duty, obedience, self-denial are the impostures of hypocrisy. Government is absolute, and may ordain what it pleases, and no subject can complain that it does him wrong, but as long as he can escape compulsion and punishment, he is always free to disobey. Happiness consists in obtaining power and in eluding the necessity of obedience; and he that gains a throne by perfidy and murder, deserves to be truly envied. Epicurus differed but little from the propounders of the code of revolutionary despotism. All societies, he said, are founded on contract for mutual protection. Good and evil are conventional terms, for the thunderbolts of heaven fall alike on the just and the unjust. The objection to wrongdoing is not the act, but in its consequences to the wrongdoer. Wise men contrive laws, not to bind, but to protect themselves; and when they prove to be unprofitable they cease to be valid. The illiberal sentiments of even the most illustrious metaphysicians are disclosed in the saying of Aristotle, that the mark of the worst governments is that they leave men free to live as they please.