ABSTRACT
In 1952, US historian Walter Prescott Webb published an important book exploring the political and social consequences of the fact that the four-hundred-year period of European discovery and exploration at what he called the world's frontier had very recently come to a close. Webb's thesis was that this period had produced "a business boom such as the world had never known before and probably never can know again", for he concluded that the period of expansion then ending was an unusual and perhaps unique phenomenon in human history. The essential lesson of the biosphere is that it is neither indestructible in the face of human intervention nor replaceable by human effort. Indeed a delicate balance of nature throughout the ecology of the planet forms a life-sustaining system through an infinitely complex web of connections among the biosphere's components. In 1990, the UN secretary-general initiated informal discussions to try to meet the objections of the industrialized states.
