When things get bad enough, then something happens to correct the course. And it's for that reason that I speak about evolution as an error-making and an error-correcting process. And if we can be ever so much better - ever so much slightly better - at error correcting than at error making, then we'll make it.

As a child I was not interested in science. I was merely interested in things human, the human side of nature, if you like, and I continue to be interested in that. That's what motivates me.

What is ... important is that we - number one: Learn to live with each other. Number two: try to bring out the best in each other.

I have the impression that the new generation of young people, are coming up on the scene with a sense "ancestorhood", and with more wisdom than was evident before.

Evolution favors the survival of the wisest.

I have had dreams and I have had nightmares, but I have conquered my nightmares because of my dreams.

When I worked on the polio vaccine, I had a theory. I guided each [experiment] by imagining myself in the phenomenon in which I was interested. The intuitive realm . . . the realm of the imagination guides my thinking.