Three great forces rule the world: stupidity, fear and greed.

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.

The bigotry of the nonbeliever is for me nearly as funny as the bigotry of the believer.

You never fail until you stop trying.

Everyday is an oportunity to make a new happy ending.

You do not really understand something unless you can explain it to your grandmother.

It has often been said, and certainly not without justification, that the man of science is a poor philosopher.