We scientists are clever — too clever — are you not satisfied? Is four square miles in one bomb not enough? Men are still thinking. Just tell us how big you want it!

Words can be meaningless. If they are used in such a way that no sharp conclusions can be drawn.

If you can find any other view of the world which agrees over the entire range where things have already been observed, but disagrees somewhere else, you have made a great discovery.

I, a universe of atoms, an atom in the universe.

There's plenty of room at the bottom.

When a Caltech student asked the eminent cosmologist Michael Turner what his "bias" was in favoring one or another particle as a likely candidate to compromise dark matter in the universe, Feynmann snapped, "Why do you want to know his bias? Form your own bias!"

I do believe that there is a conflict between science and religion ... the spirit or attitude toward the facts is different in religion from what it is in science. The uncertainty that is necessary in order to appreciate nature is not easily correlated with the feeling of certainty in faith.