We start out a million years ago in a small community on some grassy plain; we hunt animals, have children, and develop a rich social, sexual, and intellectual life, but we know almost nothing about our surroundings.

The man who is too isolated grows timid, abstracted, a little odd: He stumbles along amid realities like a sailor who has just come off his ship; he has lost the sense of the human lot; he seems to look on you as if you were a "proposition" to be inserted in a syllogism, or an example to be put down in a notebook.

One of the secrets of life is to keep our intellectual curiosity acute.

Our family life was certainly not intellectual.

Intellectual property has the shelf life of a banana.

You find no man, at all intellectual, who is willing to leave London. No, Sir, when a man is tired of London, he is tired of life; for there is in London all that life can afford.