I sometimes ask myself how it came about that I was the one to develop the theory of relativity. The reason, I think, is that a normal adult never stops to think about problems of space and time. These are things which he has thought about as a child. Bu t my intellectual development was retarded,as a result of which I began to wonder about space and time only when I had already grown up.

If you can't explain something simply, you don't know enough about it.

The most evident difference springs from the important part which is played in man by a relatively strong power of imagination and by the capacity to think, aided as it is by language and other symbolically devices.

Try first to be a man of value; success will follow.

I have survived two wars, two wives and Hitler.

Sometimes one pays most for the things one gets for nothing.

Man is, at one and the same time, a solitary being and a social being.