Mathematics is really an art, not a science.

[On Richard P. Feynman's live demonstration of the rigidity of the O-rings when cold that doomed the space shuttle Challenger, killing seven astronauts:] The public saw with their own eyes how science is done, how a great scientist thinks with his hands, how nature gives a clear answer when a scientist asks her a clear question.

What the world needs is a small, compact, flexible fusion technology that could make electricity where and when it is needed. The existing fusion program is leading to a huge source of centralized power, at a price that nobody except a government can afford.

For some days I quietly worked out in my own mind the metaphysics of Cosmic Unity. The more I thought about it, the more convinced I became that it was the living truth. It was logically incontrovertible. It provided for the first time a firm foundation for ethics. It offered mankind the radical change of heart and mind that was our only hope of peace at a time of desperate danger. Only one small problem remained. I must find a way to convert the world to my way of thinking.

It's us that's really amazing.

As a working hypothesis to explain the riddle of our existence, I propose that our universe is the most interesting of all possible universes, and our fate as human beings is to make it so

If you start out with a tragic view of life, then anything since is just a bonus.