When I study philosophical works I feel I am swallowing something which I don't have in my mouth.

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

I believe in intuitions and inspirations...I sometimes FEEL that I am right. I do not KNOW that I am.

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

Never lose a holy curiosity. Try not to become a man of success but rather try to become a man of value. He is considered successful in our day who gets more out of life than he puts in. But a man of value will give more than he receives.

You see, wire telegraph is a kind of a very, very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? And radio operates exactly the same way: you send signals here, they receive them there. The only difference is that there is no cat.

If men as individuals surrender to the call of their elementary instincts, avoiding pain and seeking satisfaction only for their own selves, the result for them all taken together must be a state of insecurity, of fear, and of promiscuous misery.