Accommodating future needs and numbers to the earth's natural capacities and resources will give rise to a transformation of human values, social institutions and economic structures on an order which could ultimately approach that of the agricultural and industrial revolutions. The coming transformation is lengthy in duration: a period from a half to a full century. It is enormous in scope: a three-fold increase in world population. And it is awesome in its implications for change: the need to lower birth rates drastically; the need to provide specially for the poor and disadvantaged, the upheavals of migration, the expansion of the labour force, and the growth of metropolitan areas; the need for massive substitutes in primary energy and accompanying adjustments in agriculture and industry; the need to promote intensive environmentally-sound resource use; and the need to meet the tremendous requirements of the developing countries for food, health, education and housing, or more generally, to be equipped to handle not just "another world" but a second and third world "on top of this, equal in numbers, demands and hopes. "
Report of the Secretary-General,
United Nations Economic and