As the new century begins, it is becoming evident to urban dwellers, whether in industrial or developing countries, that there is an immanent conflict between the automobile and the city. Urban air pollution, often from automobiles, claims millions of lives. Congestion also takes a direct economic toll in rising costs in time and the use of petrol.
Another cost of cities that are devoted to cars is a psychological one, a deprivation of contact with the natural world — an "asphalt complex". There is a growing body of evidence that there is an innate human need for contact with nature. Both ecologists and psychologists have been aware of this for some time. Ecologists, led by Harvard University biologist E.O. Wilson, have formulated the "biophilia hypothesis", which argues that those who are deprived of contact with nature suffer psychologically and that this deprivation leads to a measurable decline in well-being.
Meanwhile psychologists have coined their own term — ecopsychology — in which they make the same argument. Theodore Roszak, a leader in this field, cites a study that documents humans' dependence on nature by looking at the rate of recovery of patients in a hospital in Pennsylvania. Those whose rooms overlooked gardens with grass, trees, flowers, and birds recovered from illnesses more quickly than those who were in rooms overlooking the parking lot.