"To guess what to do, you can't be a scientist unless you have a feel for the numbers."

"You have no responsibility to live up to what other people think you ought to accomplish. I have no responsibility to be like what they expect me to be. It's their mistake, not my failing."

"I have a theory that the universe is a great big safe, and that there's a combination to open it. But the combination is locked up in the safe."

"I was also a little bit of a clown."

"It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it's wrong."