Brain, n. An apparatus with which we think that we think.

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

“I think, therefore I am” is the statement of an intellectual who underrates toothaches.

Strength of mind is exercise, not rest.

The real question is not whether machines think but whether men do.

To be too conscious is an illness—a real thoroughgoing illness.

The brain is an unreliable organ, it is monstrously great, monstrously developed. Swollen, like a goiter.

Is there no way out of the mind?

Though this be madness, yet there is method in’t.

Not all heads have a brain.

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

The mind of man is capable of anything.

The march of the human mind is slow.