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.

Man, surrounded by facts, permitting himself no surprise, no intuitive flash, no great hypothesis, no risk, is in a locked cell. Ignorance cannot seal the mind and imagination more securely.

No problem can be solved from the same level of consciousness that created it.

I consider it important, indeed urgently necessary, for intellectual workers to get together, both to protect their own economic status and, also, generally speaking, to secure their influence in the political field.

Curiosity is a delicate little plant that, aside from stimulation, stands mainly in need of freedom.

While I am a convinced pacifist there are circumstances in which I believe the use of force is appropriate - namely, in the face of an enemy unconditionally bent on destroying me and my people.

Belief in an external world independent of the perceiving subject is the basis of all natural science.