Four elements, Hydrogen, carbon, oxygen and nitrogen, also provide an example of the astonishing togetherness of our universe. They make up the "organic" molecules that constitute living organisms on a planet, and the nuclei of these same elements interact to generate the light of its star. Then the organisms on the planet come to depend wholly on that starlight, as they must if life is to persist. So it is that all life on the Earth runs on sunlight. [Referring to photosynthesis]

I have lived much of my life among molecules. They are good company. I tell my students to try to know molecules, so well that when they have some question involving molecules, they can ask themselves, What would I do if I were that molecule? I tell them, Try to feel like a molecule; and if you work hard, who knows? Some day you may get to feel like a big molecule!

There was a golden period that I look back upon with great regret, in which the cheapest of experimental animals were medical students. Graduate students were even better. In the old days, if you offered a graduate student a thiamine-deficient diet, he gladly went on it, for that was the only way he could eat. Science is getting to be more and more difficult.

I think I know what is bothering the students. I think that what we are up against is a generation that is by no means sure that it has a future.

A scientist is in a sense a learned small boy. There is something of the scientist in every small boy. Others must outgrow it. Scientists can stay that way all their lives.

We are living in a world in which all wars are wars of defense.

The only use for an atomic bomb is to keep somebody else from using one. It can give us no protection - only the doubtful satisfaction of retaliation...