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

The most potent weapon in the hands of the oppressor is the mind of the oppressed.

The sleep of reason produces monsters.

Your mind’s got to eat, too.

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

What a torture to talk to filled heads that allow nothing from the outside to enter them.

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

The universe is an object of thought at least as much as it is a means of satisfying needs.

Understanding is a very dull occupation.

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

Madness need not be all breakdown. It may also be breakthrough.

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

The mind is not, I know, a highway but a temple, and its doors should not be carelessly left open.