Since I do not forsee that atomic energy is to be a great boon for a long time, I have to say that for the present it is a menace. Perhaps it is well that it should be. It may intimidate the human race into bringing order into its international affairs, which, without the presence of fear, it would not do.

Everyone knew it was impossible, until a fool who didn't know came along and did it.

Imagination is everything. It is the preview of life's coming attractions.

We owe a lot to the Indians, who taught us how to count, without which no worthwhile scientific discovery could have been made.

Intelligent life on other planets? I'm not even sure there is on earth!

I never teach my pupils, I only attempt to provide the conditions in which they can learn.

For science can only ascertain what is, but not what should be, and outside of its domain value judgments of all kinds remain necessary. Religion, on the other hand, deals only with evaluations of human thought and action: it cannot justifiably speak of facts and relationships between facts.