From Sir Philip Sidney, The Defence of Poesy (1579/1593)

But the historian, being captived to the truth of a foolish world, is many times a terror from well-doing, and an encouragement to unbridled wickedness. For see we not valiant Miltiades rot in his fetters? The just Phocion and the accomplished Socrates put to death like traitors? The cruel Severus live prosperously? The excellent Severus miserably murdered? Sylla and Marius dying in their beds? Pompey and Cicero slain then, when they would have thought exile a happiness? See we not virtuous Cato driven to kill himself, and rebel Caesar so advanced that his name yet, after sixteen hundred years, lasteth in the highest honor? And mark but even Caesar`s own words of the forenamed Sylla - who in that only did honestly, to put down his dishonest tyranny - literas nescivit: as if want of learning caused him to do well. He meant it not by poetry, which, not content with earthly plagues, deviseth new punishments in hell for tyrants; nor yet by philosophy, which teacheth occidendos esse; but, no doubt, by skill in history, for that indeed can afford you Cypselus, Periander, Phalaris, Dionysius, and I know not how many more of the same kennel, that speed well enough in their abominable injustice or usurpation.