Selected Quotes of Richard Feynman

"The first principle is that you must not fool yourself - and you are the easiest to fool. "
   --Richard Feynman

"Physics is like sex. Sure, it may give some practical results, but that's not why we do it. "
   --Richard Feynman

"I think it's much more interesting to live not knowing than to have answers which might be wrong. "
   --Richard Feynman

"If you think you understand quantum mechanics you don't understand quantum mechanics  "
   --Richard Feynman