"Man reaches the maturity of his reasoning and mental faculties scarcely before he is eight-and-twenty; woman when she is eighteen; but hers is reason of very narrow limitations."

"The more intelligent a man is, the more he suffers."

"A man can be himself only so long as he is alone; and if he does not love solitude, he will not love freedom; for it is only when he is alone that he is really free."

"The greatest error of all is to try to be happy."

"Man is the only animal that causes pain to others for the mere pleasure of doing it."