No man is so foolish but he may sometimes give another good counsel, and no man so wise that he may not easily err if he takes no other counsel than his own. He that is taught only by himself has a fool for a master. Hunter S. Thompson
No man is so much a fool as not to have wit enough sometimes to be a knave; nor any so cunning a knave as not to have the weakness sometimes to play the fool. George Savile
No man is the wiser for his learning; it may administer matter to work in, or objects to work upon; but wit and wisdom are born with a man. John Selden
No man is worth his salt who is not ready at all times to risk his well-being, to risk his body, to risk his life, in a great cause. Theodore Roosevelt