Man shapes himself through decisions that shape his environment.

But solving problems of disease is not the same thing as creating health and happiness. (...) Health and happiness are the expression of the manner in which the individual responds and adapts to the challenges that he meets in everyday life.

Any attempt to shape the world and modify human personality in order to create a self-chosen pattern of life involves many unknown consequences. Human destiny is bound to remain a gamble, because at some unpredictable time and in some unforeseeable manner nature will strike back. The multiplicity of determinants which affect biological systems limits the power of the experimental method to predict their trends and behavior.

Eradication of microbial disease is a will-o'-the-wisp; pursuing it leads into a morass of hazy biological concepts and half truths.

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

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.

The very process of living is a continual interplay between the individual and his environment, often taking the form of a struggle resulting in injury or disease.