A man has to work so hard so that something of his personality stays alive. A tomcat has it so easy, he has only to spray and his presence is there for years on rainy days.

As our circle of knowledge expands, so does the circumference of darkness surrounding it.

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.

What good is a reputation not put to good use.

Human beings can attain a worthy and harmonious life only if they are able to rid themselves, within the limits of human nature, of the striving for the wish fulfillment of material kinds. The goal is to raise the spiritual values of society.

In any conflict between humanity and technology, humanity will win.

It is my inner conviction that the development of science seeks in the main to satisfy the longing for pure knowledge.