To refuse a hearing to an opinion, because they are sure that it is false, is to assume that their certainty is the same thing as absolute certainty. All silencing of discussion is an assumption of infallibility.
John Stuart MillThere is one plain rule of life. Try thyself unweariedly till thou findest the highest thing thou art capable of doing, faculties and outward circumstances being both duly considered, and then do it.
John Stuart MillIn this age, the mere example of nonconformity, the mere refusal to bend the knee to custom, is itself a service.
John Stuart MillComplete liberty of contradicting and disproving our opinion, is the very condition which justifies us in assuming its truth for purposes of action.
John Stuart MillIt must be granted that in every syllogism, considered as an argument to prove the conclusion, there is a petitio principii. When we say, All men are mortal Socrates is a man therefore Socrates is mortal; it is unanswerably urged by the adversaries of the syllogistic theory, that the proposition, Socrates is mortal.
John Stuart MillChristian morality (so called) has all the characters of a reaction.... In its horror of sensuality, it made an idol of asceticism, which has been gradually compromised away into one of legality. It holds out the hope of heaven and the threat of hell, as the appointed and appropriate motives to a virtuous life - in this falling far below the best of the ancients, and doing what lies in it to give to human morality an essentially selfish character.... It is essentially a doctrine of passive obedience; it inculcates submission to all authorities found established.
John Stuart Mill