In action a great heart is the chief qualification. In work, a great head.

Hatred is an affair of the heart; contempt that of the head.

My only great qualification for being put at the head of the Navy is that I am very much at sea

Reading is equivalent to thinking with someone else's head instead of with one's own.

To live alone is the fate of all great souls.

Hatred comes from the heart; contempt from the head; and neither feeling is quite within our control