The whole theory of sacrifice will be better understood if we grasp the fact that it was born of fear. When a nation sacrificed out of gratitude or in apparent joyous exultation, it was in memory of days when they suffered and their gratitude was as much a propitiation as anything else. Born in fear, the next step in the development of sacrifice was to economize “without impairing efficiency.”[197] The result of this second effort is seen in ingenious devices by which the burden on the worshipper is lightened by his substituting something less valuable than what he is supposed to offer, or what the god is supposed to want, but which the worshipper believes will be acceptable. These substitutions are always made when the forces of nature are treating man more kindly and when his attitude toward his gods is less fearful, for the mind of man in time of plenty and security has always presupposed that time to be when the gods are more or less drowsy. With some primitive peoples, the sacrifice began as an offering of a meal to the ancestor who had gone before, but as with all primitive peoples the determining factor in religion is fear rather than affection, it became a method of soliciting favours for the future, and such were the sacrifices among the Greeks and Romans, the Hebrews, the Aryans, and the Chinese.[198] Primitive man, when unwelcome children were born, found easy excuse for getting rid of them by offering them as a sacrifice to the impatient and fearful gods. That at some stage in the development of the parental instinct the excuse that the gods must be propitiated was needed to quiet the awakening mother love, is more than likely. And surely, no more crushing answer could there be to the request to allow a child to live than that the gods were angry and had to be propitiated. Another reason given for offering children was that, having just come from the other world, they were nearer to the gods and freer of sin and therefore more acceptable. Such reasoning argues a stage far in advance of the cannibal who ate his own children under the idea that he was propitiating an angry god. “The institutions of man develop with considerable uniformity all over the globe, although as races advance, they naturally diverge more or less under the influence of different climate, food, and other conditions.”[199] Cannibalism was one of the earliest stages to which we are able to trace many of the customs even of today, and the idea of sacrifice of children undoubtedly had its origin in primitive cannibalistic feasts, “ceremonies that were softened by the rise of civilization as well as migration to more fertile land and an abundance of food sufficient to make the substitution of an animal for a human possible.”[200]