Any man could, if he were so inclined, be the sculptor of his own brain.

What the brain does by itself is infinitely more fascinating and complex than any response it can make to chemical stimulation.

What is outside my mind means nothing to it.

The sleep of reason produces monsters.

The highest possible stage in moral culture is when we recognize that we ought to control our thoughts.

We need strength, we need energy, we need quickness, and we need brain in this country to turn it around.

From a man’s face, I can read his character. If I can see him walk, I know his thoughts.

Don’t lose your mind unless you have paid for it.

Imagination is the secret and marrow of civilization. It is the very eye of faith.

Brains are the only things worth having in this world.

The brain may be regarded as a kind of parasite of the organism, a pensioner, as it were, who dwells with the body.

A mind lively and at ease can do with seeing nothing, and can see nothing that does not answer.

Sooner or later if the activity of the mind is restricted anywhere, it will cease to function even where it is allowed to be free.