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.

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

Human life is now molded to a large extent by the changes that man has brought about in his external environment and by his attempts at controlling body and soul.

Biologically, man is still the great amateur of the animal kingdom; he is unique in his lack of anatomical and physiological specialization.

It is a disturbing fact that Western civilization, which claims to have achieved the highest standard of health in history, finds itself compelled to spend ever-increasing sums for the control of disease.

In man, at least, satisfaction is commonly followed by boredom.

There is a demon in technology. It was put there by man and man will have to exorcise it before technological civilization can achieve the eighteenth-century ideal of humane civilized life.