The principle of science, the definition, almost, is the following: The test of all knowledge is experiment. Experiment is the sole judge of scientific "truth." But what is the source of knowledge? Where do the laws that are to be tested come from? Experiment, itself, helps to produce these laws, in the sense that it gives us hints. But also needed is imagination to create from these hints the great generalizations--to guess at the wonderful, simple, but very strange patterns beneath them all, and then to experiment to check again whether we have made the right guess.

But there is nothing in biology yet found that indicates the inevitability of death.

No problem is too small or too trivial if we can really do something about it.

You should not fool the laymen when you're talking as a scientist... . I'm talking about a specific, extra type of integrity that is not lying, but bending over backwards to show how you're maybe wrong, [an integrity] that you ought to have when acting as a scientist. And this is our responsibility as scientists, certainly to other scientists, and I think to laymen.

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

I learned very early the difference between knowing the name of something and knowing something.

Philosophy of science is about as useful to scientists as ornithology is to birds.