This chapter is constructed on an observation in apparent contradiction to the pristine “affluence” the author have just taken so much trouble to defend: the primitive economies are underproductive. The major evidence for underexploitation of productive resources comes from agricultural societies, especially those practicing slash-and-bum cultivation. Slash-and-burn, an agriculture of neolithic origin, is widely practiced today in tropical forests. It is a technique for opening up and bringing under cultivation a patch of forest land. Any “productive capacity” so estimated is partial and derivative: partial, because the investigation is restricted in advance to the cultivation of food, other dimensions of production left aside; derivative, because “capacity” takes the form of a population maximum. The Kuikuru illustrate another kind of extreme: the scale of the disparity that may exist between potential and reality.