It followed from the special theory of relativity that mass and energy are both but different manifestations of the same thing...

I have never belonged wholeheartedly to country or State, to my circle of friends or even to my own family... Such isolation is sometimes bitter, but I do not regret being cut off from the understanding and sympathy of other men. I lose something by it,to be sure, but I am compensated for it in being rendered independent of the customs, opinions and prejudices of others, and am not tempted to rest my peace of mind upon such shifting foundations.

When I was still a rather precocious young man, I already realized most vividly the futility of the hopes and aspirations that most men pursue throughout their lives.

The mind can proceed only so far upon what it knows and can prove. There comes a point where the mind takes a higher plane of knowledge, but can never prove how it got there. All great discoveries have involved such a leap

Combinatory play seems to be the essential feature in productive thought.

For the most part, I do the thing which my own nature prompts me to do. It is embarrassing to earn so much respect and love for it.

Problems cannot be solved by thinking within the framework in which the problems were created.