We are at the very beginning of time for the human race. It is not unreasonable that we grapple with problems. But there are tens of thousands of years in the future. Our responsibility is to do what we can, learn what we can, improve the solutions, and pass them on.

The whole question of imagination in science is often misunderstood by people in other disciplines. ... They overlook the fact that whatever we are allowed to imagine in science must be consistent with everything else we know.

I would rather have questions that can't be answered than answers that can't be questioned.

There is no authority who decides what is a good idea.

If a guy tells me the probability of failure is 1 in 100,000, I know he's full of crap.

This is not very important what I'm doing. I'm just proving something.

Know your place in the world and evaluate yourself fairly, not in terms of the naïve ideals of your own youth, nor in terms of what you erroneously imagine your teacher's ideals are.