Clearly, health and disease cannot be defined merely in terms of anatomical, physiological, or mental attributes. Their real measure is the ability of the individual to function in a manner acceptable to himself and to the group of which he is a part.

Man will survive as a species for one reason: He can adapt to the destructive effects of our power-intoxicated technology and of our ungoverned population growth, to the dirt, pollution and noise of a New York or Tokyo. And that is the tragedy. It is not man the ecological crisis threatens to destroy but the quality of human life.

Human destiny is bound to remain a gamble, because at some unpredictable time and in some unforeseeable manner nature will strike back.

Human life implies adventure, and there is no adventure without struggles and dangers.

Nature always strikes back. It takes all the running we can do to remain in the same place.

... each type of civilization has had diseases peculiar to it and at each period the various social groups in any community also have differed in this regard.

Pathological states are the consequence of several determinate factors acting simultaneously...The manifestations of any given agent differ profoundly from one person to another. ...Each noxious agent can express itself by a great variety of different pathological states. ...Different agents can elicit similar reactions. ...The total environment and the (interior medium) constitute a multifactorial system.