Whoever has overthrown an existing law of custom has always first been accounted a bad man: but when, as did happen, the law could not afterwards be reinstated and this fact was accepted, the predicate gradually changed; - history treats almost exclusively of these bad men who subsequently became good men!
Friedrich Nietzsche, Maudemarie Clark, Brian Leiter (1997). “Nietzsche: Daybreak: Thoughts on the Prejudices of Morality”, p.18, Cambridge University Press