For the most part we humans live with the false impression of security and a feeling of being at home in a seemingly familiar and trustworthily physical and human environment. But when the expected course of everyday life is interrupted, we realize that we are like shipwrecked people trying to keep their balance on a miserable plank in the open sea, having forgotten where they came from and not knowing whether they are drifting. But once we fully accept this, life becomes easier and there is no longer any disappointment.
A theory is the more impressive the greater the simplicity of its premises is, the more different kinds of things it relates, and the more extended its area of applicability.
I do not share the crusading spirit of the professional atheist whose fervor is mostly due to a painful act of liberation from the fetters of religious indoctrination received in youth. I prefer an attitude of humility corresponding to the weakness of our intellectual understanding of nature and of our own being.
Einstein was once asked how many feet are in a mile. Einstein's reply was "I don't know, why should I fill my brain with facts I can find in two minutes in any standard reference book?
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.
It is only to the individual that a soul is given. And the high destiny of the individual is to serve rather than to rule, or to impose himself in any other way.
You imagine that I look back on my life's work with calm satisfaction. But from nearby it looks quite different. There is not a single concept of which I am convinced that it will stand firm, and I feel uncertain whether I am in general on the right track.