Anybody who does it need not be a genius. Genius has never been supposed to be a particularly good teacher of any art. It is better that the teacher of the Art of Thinking should not be a person who knows no difficulty in thinking, or produces such brilliant thoughts that they will be disheartening to the tyro. A delicate physician does not give the example of health-any woodsman can do that-he only gives the example of a small capital of health intelligently increased: yet, we know he can be more useful from his comprehension of indifferent health and from his appreciation of hygiene, and we often prefer him.