Death seems to have been a rather late invention in evolution. One can go a long way in evolution before encountering an authentic corpse.

We have fallen in love with the body. That's that thing that looks back at us from the mirror. That's the repository of that lovely identity that you keep chasing all your life.

Not all living creatures die. An amoeba, for example, need never die; it need not even, like certain generals, fade away. It just divides and becomes two new amoebas.

Civilization will end within 15 or 30 years unless immediate action is taken against problems facing mankind.

The great questions are those an intelligent child asks and, getting no answers, stops asking.

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!

About two million years ago, man appeared. He has become the dominant species on the earth. All other living things, animal and plant, live by his sufferance. He is the custodian of life on earth, and in the solar system. It's a big responsibility.