Man becomes man only by his intelligence, but he is man only by his heart.
For purposes of action nothing is more useful than narrowness of thought combined with energy of will.
Conquering any difficulty always gives one a secret joy, for it means pushing back a boundary-line and adding to one's liberty.
The man who has no inner-life is a slave to his surroundings.
Self-interest is but the survival of the animal in us. Humanity only begins for man with self-surrender.
Uncertainty is the refuge of hope.
