Abstract
THERE is obviously a close relation between any rational attempt to “explain” the world in terms of its activities and the prevailing views on causality. Primitive thought usually peopled the physical world with unpredictable spirits of all kinds; gods and witchdoctors were believed to influence the course of events in ways that ordinary mortals could not follow. In such a world, the intrinsic legality of events might pass almost unnoticed; it was recognizable only when the distinction between God, Man, and Nature came to be clearly drawn, or only as the effects of Divine and human causality came to be disentangled from natural causal processes, which would then become describable in scientific terms. The history of thought shows that these distinctions, so obvious to us, are not easy ones to come by.