I wouldn't want to live if I did not have my work. In any case, it's good that I'm already old and personally don't have to count on a prolonged future.
There is, fortunately, a minority composed of those who recognize early in their lives that the most beautiful and satisfying experiences open to humankind are not derived from the outside, but are bound up with the development of the individual's own feeling, thinking and acting. The genuine artists, investigators and thinkers have always been persons of this kind. However inconspicuously the life of these individuals runs its course, none the less the fruits of their endeavors are the most valuable contributions which one generation can make to its successors.
... on principle, it is quite wrong to try founding a theory on observable magnitudes alone. In reality the very opposite happens. It is the theory which decides what we can observe.
Anybody who really wants to abolish war must resolutely declare himself in favor of his own country's resigning a portion of sovereignty in place of international institutions.
In living through this great epoch, it is difficult to reconcile oneself to the fact that one belongs to that mad, degenerate species that boasts of its free will. How I wish that somewhere there existed an island for those who are wise and of good will. In such a place even I should be an ardent patriot!
I like to experience the universe as one harmonious whole. Every cell has life. Matter, too, has life; it is energy solidified. Our bodies are like prisons, and I look forward to be free, but I don't speculate on what will happen to me. I live here now, and my responsibility is in this world now.
Pure mathematics is, in its way, the poetry of logical ideas. ... [By seeking] logical beauty spiritual formulas are discovered necessary for the deeper penetration into the laws of nature.