The total absence of humor from the Bible is one of the most singular things in all literature.

Civilization advances by extending the number of important operations which we can perform without thinking about them. Operations of thought are cavalry charges in a battle - they are limited in number, they require fresh horses, and must only be made at decisive moments.

It is the business of the future to be dangerous.

A great society is a society in which its men of business think greatly of their functions.

People make the mistake of talking about 'natural laws.' There are no natural laws. There are only temporary habits of nature.

No one who achieves success does so without acknowledging the help of others. The wise and confident acknowledge this help with gratitude.

The worst that happened to men of science was that Galileo suffered an honorable detention and a mild reproof, before dying peacefully in his bed.