What happens in the mind of man is always reflected in the disease of his body.

Social evolution may be the result of intention, but it rarely, if ever, produces the result intended.

Each civilization has its own kind of pestilence and can control it only by reforming itself.

To ward off disease or recover health, people as a rule find it easier to depend on healers than to attempt the more difficult task of living wisely.

Life is short, the art is long, the problems pressing.

You cannot see the Milky Way in New York City any more ... We risk the loss of our sensual perception. And if you lose those, naturally, you try to compensate by other stimulations, by very loud noises, or by bright lights or drugs.

As long as mankind is made up of independent individuals with free will, there cannot be any social status quo. Men will develop new urges, and these will give rise to new problems, which will require ever new solutions. Human life implies adventure, and there is no adventure without struggles and dangers.