Montaigne on Education:

...this education is to be carried on with severe gentleness, not as is customary. Instead of being invited to letters, children are shown in truth nothing but horror and cruelty. Away with violence and compulsion! There is nothing to my mind which so depraves and stupefies a wellborn nature. If you would like him to fear shame and chastisement, don't harden him to them. Harden him to sweat and cold, wind and sun, and the dangers that he must scorn; wean him from all softness and delicacy in dressing and sleeping, eating and drinking; accustom him to everything. Let him not be a pretty boy and a little lady, but a lusty and vigorous youth.

William James in The Sentiment of Rationality:

He who commands himself not to be credulous of God, of duty, of freedom, of immortality, may again and again be indistinguishable from him who dogmatically denies them. Scepticism in moral matters is an active ally of immorality. Who is not for is against. The universe will have no neutrals in these questions. In theory as in practice, dodge or hedge, or talk as we like about a wise skepticism, we are really doing voluntary military service for one side or the other.