ABSTRACT
An economist with no training in the natural sciences cannot determine whether the threat of doom is an immediate and real one. The answer to this fundamental question depends upon scientific and technological assessment of such matters as the ultimate effects of certain ecological and atmospheric disturbances, the technological prospects of substituting one material for another, and the prospects of a more direct harnessing of solar energy. There is much disagreement among highly qualified natural scientists on these questions. An economist will not grudge the natural scientists their little squabbles; but he would be foolish to try to judge between them.
