In the middle of difficulty lies opportunity.

It's not than I'm so smart, it's just that I stay with problems longer.

How can cosmic religious feeling be communicated from one person to another, if it can give rise to no definite notion of a God and no theology? In my view, it is the most important function of art and science to awaken this feeling and keep it alive in those who are receptive to it.

Life is a preparation for the future; and the best preparation for the future is to live as if there were none.

Just because you don't believe in something doesn't mean it isn't true.

If I can't picture it, I can't understand it.

Everything that is really great and inspiring is created by the individual who can labor in freedom.

Heroism on command, senseless violence, and all the loathsome nonsense that goes by the name of patriotism - how passionately I hate them!

The only thing more dangerous than ignorance is arrogance.

If a man aspires towards a righteous life, his first act of abstinence is from injury to animals.