Balancing statistics on population against our stock of resources, a young geochemist considers the ""what next?"" of both and comes across with some challenging posers about a future on an earth we are constantly draining of food, energy and material. Dividing the world into three groups, agrarian, industrial and transitional- he examines the interrelationships of each, in a serious appraisal which where it lacks the humor that could give it a wider audience, will nevertheless provoke argument. Fine for high-school studies.