By relieving the brain of all unnecessary work, a good notation sets it free to concentrate on more advanced problems, and in effect increases the mental power of the race.

Religion is the last refuge of human savagery.

I always feel that I have two duties to perform with a parting guest: one, to see that he doesn't forget anything that is his; the other, to see that he doesn't take anything that is mine.

It is the business of future to be dangerous.... The major advances in civilization are processes that all but wreck the societies in which they occur.

In formal logic, a contradiction is the signal of defeat, but in the evolution of real knowledge it marks the first step in progress toward a victory.

The future belongs to those who can rise above the confines of the earth.

One main factor in the upward trend of animal life has been the power of wandering.