Once when a band of !Kung Bushmen had performed their rain rituals, a small cloud appeared on the horizon, grew and darkened. Then rain fell. But the anthropologists who asked if the Bushmen reckoned the rite had produced the rain, were laughed out of court (Marshall, 1957). How naive can we get about the beliefs of others? Old anthropological sources are full of the notion that primitive people expect rites to produce an immediate intervention in their affairs, and they poke kindly fun at those who supplement their rituals of healing with European medicine, as if this testified to lack of faith. The Dinka perform an annual ceremony to cure malaria. The ceremony is timed for the month in which it is to be expected that malaria will soon abate. A European observer who witnessed it remarked dryly that the officiant ended by urging everyone to attend the clinic regularly if they hoped to get well (Lienhardt 1961).