I think physicists are the Peter Pans of the human race. They never grow up and they keep their curiosity.

To me, science is an expression of the human spirit, which reaches every sphere of human culture. It gives an aim and meaning to existence as well as a knowledge, understanding, love, and admiration for the world. It gives a deeper meaning to morality and another dimension to esthetics.

My mother made me a scientist without ever intending to. Every other Jewish mother in Brooklyn would ask her child after school: So? Did you learn anything today? But not my mother. “Izzy,” she would say, “did you ask a good question today?” That difference — asking good questions — made me become a scientist.

He who thinks half-heartedly will not believe in God; but he who really thinks has to believe in God.

No one alive has been found today, only the dead.

I'm disappointed, ... I spent several years there. I was one of the founding members of their Institute for Theoretical Physics. I would have thought they'd be proud to claim me.