Human beings are not condemned, because of their biological constitution, to annihilate each other or to be at the mercy of a cruel, self-inflicted fate.

Time is not at all what it seems. It does not flow in only one direction, and the future exists simultaneously with the past.

How can it be that mathematics, being after all a product of human thought which is independent of experience, is so admirably appropriate to the objects of reality?

I think that only daring speculation can lead us further and not accumulation of facts.

The bitter and the sweet come from the outside, the hard from within, from one's own efforts.

I think and think for months and years. Ninety-nine times, the conclusion is false. The hundredth time I am right.

I don't believe in mathematics.