"I asked him once, 'How do you tell when a mathematical argument is correct?' He said, 'If it's beautiful, it's correct.'"

"Nature uses only the longest threads to weave her patterns, so each small piece of her fabric reveals the organization of the entire tapestry."

"If you think you understand quantum mechanics, you don't understand quantum mechanics."

"I don't have to be polite when I'm doing science."

"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!"