False and doubtful positions, relied upon as unquestionable maxims, keep those who build on them in the dark from truth. Such are usually the prejudi… - John Locke

A young man before he leaves the shelter of his father's house, and the guard of a tutor, should be fortify'd with resolution, and made acquainted with men, to secure his virtues, lest he should be led into some ruinous course, or fatal precipice, before he is sufficiently acquainted with the dangers of conversation, and his steadiness enough not to yield to every temptation.

You must do nothing before him, which you would not have him imitate. If any thing escape you, which you would have pass as a fault in him, he will be sure to shelter himself under your example, and shelter himself so as that it will not be easy to come at him, to correct it in him the right way.

It is only practice that improves our minds as well as bodies, and we must expect nothing from our understandings any farther than they are perfected by habits.