The unleashed power of the atom has changed everything save our modes of thinking and we thus drift toward unparalleled catastrophe.

Adversity introduces a man to himself.

The scientist finds his reward in what Henri Poincare calls the joy of comprehension, and not in the possibility of application to which any discovery may lead.

I do not much believe in education. Each person ought to be his or her own model, however frightful that may be.

I am convinced there is only one way to eliminate these grave evils, namely through the establishment of a socialist economy, accompanied by an educational system which would be oriented toward social goals.

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?

The grand aim of all science is to cover the greatest number of empirical facts by logical deduction from the smallest number of hypotheses or axioms.