Fools rush in where wise men fear to trade.
When a person puts his best foot forward and gets it stepped on, that's life.
The surest sign that you haven't any sense is to argue with one who hasn't.
If you can't keep up, drag them down to your level.
A philosopher is a blind man in a dark room looking for a black cat that isn't there. A theologian is the man who finds it.
Expert: a man who makes three correct guesses consecutively.