"The ass is the only animal that can't be improved by cross-breeding."

"The only way to keep your health is to eat what you don't want, drink what you don't like, and do what you'd rather not."

"Why shouldn't I be an optimist? I have nothing to lose."

"I have found that there ain't no surer way to find out whether you like people or hate them than to travel with them."

"The trouble is not in dying for a friend, but in finding a friend worth dying for."