So if cheerfulness knocks at our door, we should throw it wide open, for it never comes inopportunely. Instead of that, we often make scruples about letting it in. We want to be quite sure that we have every reason to be contented; then we are afraid that cheerfulness of spirits may interfere with serious reflections or weighty cares.

Therefore, in the blessings as well as in the ills of life, less depends upon what befalls us than upon the way in which it is met, that is, upon the kind and degree of our general susceptibility.

The most general survey shows us that the two foes of human happiness are pain and boredom.