This being granted, two rival tendencies must be reckoned with. In the first place, moral development, with its influence on religious ideas, worked towards the suppression of the horrible custom of human sacrifice, whilst at the same time extirpating the taste and desire for human flesh. For we must not forget that where cannibalism still reigns, human flesh is regarded as the most delicious of foods; and the Greek mythology has preserved legends and myths that are connected with the very epoch at which human sacrifices first became an object of horror to gods and men. But, in the second place, in virtue of the strange persistency of rites and usages connected with religion, human sacrifices prevailed in many places when cannibalism had completely disappeared from the habits and tastes of the population. Thus the Semites of Western Asia and the Çivaïte Hindus, the Celts, and some of the populations of Greece and Italy, long after they had renounced cannibalism, still continued to sacrifice human beings to their deities. And this gives us the clue to a third phase, which was actually realized in Mexico before the conquest. Cannibalism, in ordinary life, was no longer practised. The city of Mexico underwent all the horrors of famine during the siege conducted by Fernando Cortes. When the Spaniards finally entered the city, they found the streets strewn with corpses, which is a sufficient proof that human flesh was not eaten even in dire extremities. And, nevertheless, the Aztecs not only pushed human sacrifices to a frantic extreme, but they were _ritual cannibals_, that is to say, there were certain occasions on which they ate the flesh of the human victims whom they had immolated. This practice was connected with another religious conception, grafted upon the former one. Almost everywhere, but especially amongst the Aztecs, we find the notion that the victim devoted to a deity, and therefore destined to pass into his substance and to become by assimilation an integral part of him, is already co-substantial with him, has already become part of him; so that the worshipper in his turn, by himself assimilating a part of the victim's flesh, unites himself in substance with the divine being. And now observe that in all religions the longing, whether grossly or spiritually apprehended, to enter into the closest possible union with the adored being is fundamental. This longing is inseparable from the religious sentiment itself, and becomes imperious wherever that sentiment is warm; and this consideration is enough to convince us that it is in harmony with the most exalted tendencies of our nature, but may likewise, in times of ignorance, give rise to the most deplorable aberrations.