But these few are the salt of the earth; without them, human life would become a stagnant pool. Not only is it they who introduce good things which did not before exist, it is they who keep the life in those which already existed.
John Stuart MillHe must be able to hear them [the counter arguments] from persons who actually believe them; who defend them in earnest, and do their very utmost for them. He must know them in their most plausible and persuasive form; he must feel the whole force of the difficulty which the true view of the subject has to encounter and dispose of; else he will never really possess himself of the portion of truth which meets and removes that difficulty.
John Stuart MillHowever unwillingly a person who has a strong opinion may admit the possibility that his opinion may be false, he ought to be moved by the consideration that, however true it may be, if it is not fully, frequently, and fearlessly discussed, it will be held as a dead dogma, not a living truth.
John Stuart MillI have a hundred times heard him say, that all ages and nations have represented their gods as wicked, in a constantly increasing progression; that mankind have gone on adding trait after trait till they reached the most perfect conception of wickedness which the human mind could devise, and have called this God, and prostrated themselves before it.
John Stuart Mill