The natural world is not only a set of constraints but of contexts within which we can more fully realize our dreams.

The human cardiovascular system evolved as part of the physiology of [prehistoric] hunters, who ran for their lives.

To the desert go profits and hermits, through deserts go pilgrims and exiles. Here the leaders of the great religions have sought the therapeutic and spiritual values of retreat, not to escape but to find reality.

All around us, aspects of the modern world - diet, exercise, medicine, art, work, family, philosophy, economics, ecology, psychology - have begun a long circle back toward their former coherence. Whether they can arrive before the natural world is damaged beyond repair and madness destroys humanity, we cannot tell.

The natural world is not only a set of constraints but of contexts within which we can more fully realize our dreams.

Careless of waste, wallowing in refuse, exterminating the enemies . . . despising age, denying human natural history, fabricating pseudotraditions, swamped in the repeated personal crises of the aging preadolescent; all are familiar images of American society. They are signs of private nightmares of incoherence and disorder in broken climaxes where technologies in pursuit of mastery create ever-worsening problems - private nightmares expanded to a social level.

When men do not run they are likely to die prematurely from dysfunction of the heart and vascular systems or from disabling chronic disease.