Happiness of any given life is to be measured, not by its joys and pleasures, but by the extent to which it has been free from suffering-from positive evil.

For, after all, the foundation of our whole nature, and, therefore, of our happiness, is our physique, and the most essential factor in happiness is health, and, next in importance after health, the ability to maintain ourselves in independence and freedom from care.

There is only one healing force, and that is nature; in pills and ointments there is none. At most they can give the healing force of nature a hint about where there is something for it to do.

Physics is unable to stand on its own feet, but needs a metaphysics on which to support itself, whatever fine airs it may assume towards the latter.

Politeness is to human nature what warmth is to wax.

Boredom is an evil that is not to be estimated lightly. It can come in the end to real despair. The public authority takes precautions against it everywhere, as against other universal calamities.

Knowledge is to certain extent a second existence.