"Scientific knowledge is a body of statements of varying degrees of certainty—some most unsure, some nearly sure, but none absolutely certain."

"I don't know what's the matter with people: they don't learn by understanding; they learn by some other way — by rote or something. Their knowledge is so fragile!"

"You know, the dumbest goddamn student you ever saw can understand things if you explain them right. So if you can’t explain it, it’s because you don’t understand it."

"I'm not a very good scientist. I'm just a very curious person."

"I have a lot of fun. I've always had a lot of fun. I don't know why I should stop."