A retentive memory may be a good thing, but the ability to forget is the true token of greatness.

The average man believes a thing first, and then searches for proof to bolster his opinion

Nature: The unseen intelligence which loved us into being, and is disposing of us by the same token

Progress comes from the intelligent use of experience.

To know the great men dead is compensation for having to live with the mediocre.

One machine can do the work of fifty ordinary men. No machine can do the work of one extraordinary man.

Every tyrant who ever lived has believed in freedom — for himself.