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

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.

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

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

There is no female mind. The brain is not an organ of sex. As well speak of a female liver.

The march of the human mind is slow.

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

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

What is outside my mind means nothing to it.

The sleep of reason produces monsters.

The mind of man is capable of anything.

Sanity is madness put to good uses; waking life is a dream controlled.

It is far, far better and much safer to have a firm anchor in nonsense than to put out on the troubled seas of thought.