No philosopher is more emphatic about the opposition between law and tyranny than Plato. He defines a tyrant as a ruler who is at liberty to do what he pleases, to kill, to exile, to follow his own pleasure in every act, and he condemns tyranny in a number of different contexts. In the Seventh Letter, he urges that Sicily should not be subject to the despot, but to law. In the Eighth Letter, he says that “either servitude or freedom, when it goes to extremes, is an utter bane. … The due measure of servitude is to serve God. The extreme of servitude is to serve man. The god of sober men is law.” To substitute the rule of law for tyranny ought to be the aim of every ruler, for only in that way could a city prosper. Indeed, so obvious is this truth, Plato concludes, that anyone disposed to establish a tyranny should “turn back and to flee for their lives. … Let them endeavor to put on the form of a king and to be subject to kingly laws, enjoying the highest honors by the consent of willing subjects and of the laws.” In the Statesman, Plato describes as the best of all constitutions “The rule of one man, if it has been kept within the traces, so to speak, by the written rules we call laws,” and he warns that when the rule of one man is “lawless it is hard, and the most grievous to have to endure.”