Putting a man in space is a stunt: the man can do no more than an instrument, in fact can do less. There are far more serious things to do than indulge in stunts. . . . I do not discard completely the value of demonstrating to the world our skills. Nor do I undervalue the effect on morale of the spectacular. But the present hullabaloo on the propaganda aspects of the program leaves me entirely cool.

Scientific progress on a broad front results from the free play of free intellects, working on subjects of their own choice, in the manner dictated by their curiosity for exploration of the unknown.

If scientific reasoning were limited to the logical processes of arithmetic, we should not get very far in our understanding of the physical world

A belief may be larger than a fact. A faith that is overdefined is the very faith most likely to prove inadequate to the great moments of life.

Publication has been extended far beyond our present ability to make real use of the record.

The camera hound of the future wears on his forehead a lump a little larger than a walnut.

Basic scientific research is scientific capital.