First you guess. Don't laugh, this is the most important step. Then you compute the consequences. Compare the consequences to experience. If it disagrees with experience, the guess is wrong. In that simple statement is the key to science. It doesn't matter how beautiful your guess is or how smart you are or what your name is. If it disagrees with experience, it's wrong. That's all there is to it.

The test of all knowledge is experiment.

I learned from her that every woman is worried about her looks, no matter how beautiful she is.

All theoretical chemistry is really physics; and all theoretical chemists know it.

Ordinarily it would take me about fifteen minutes to get a hallucination going," wrote Feynman, "but on a few occasions, when I smoked some marijuana beforehand, it came very quickly.

Scientists are explorers. Philosophers are tourists.

Thank you very Much, I enjoyed myself