More quotes by Richard Feynman

"Science is what we have learned about how to keep from fooling ourselves."
"Philosophy of science is about as useful to scientists as ornithology is to birds."
"Physics is like sex: sure, it may give some practical results, but that's not why we do it."
"Science is like sex: sometimes something useful comes out, but that is not the reason we are doing it."
"The first principle is that you must not fool yourself and you are the easiest person to fool."