It has been supposed that the cult of Demeter at Eleusis was originally an agrarian cult, intended to celebrate or to induce the fertility of the soil. But the chief significance of the mysteries was found in another sphere. In the mysteries, the cult goddesses, Demeter and Persephone, were thought of chiefly as goddesses of the nether world, the abode of the dead; and the mysteries were valued chiefly as providing a guarantee of a blessed immortality. How the guarantee was given is quite obscure. But the fact is well attested. Those who had been initiated into the mysteries were able to expect a better lot in the future life than the lot of the generality of men. The mysteries at Eleusis were not the only mysteries which were practised in the golden age of Greece. There were not only offshoots of the Eleusinian mysteries in various places, but also independent mysteries like those of the Kabeiri on the island of Samothrace. But the mysteries at Eleusis were undoubtedly the most important, and the others are even less fully known. The moral value of the mysteries, including those at Eleusis, should not be exaggerated. Slight allusions in pagan writers seem to point here and there to a purifying moral effect wrought by initiation. But the indications are not very clear. Certainly the secrets of Eleusis did not consist in any body of teaching, either religious or ethical. The effect was produced, not upon the intellect, but upon the emotions and upon the imagination. Thus the religion of the golden age of Greece was an anthropomorphic polytheism, closely connected with the life of the city-state, but relieved here and there by practices intended to provide more direct contact with the divine or bestow special blessing upon individuals. The religion of Greece was finally undermined by at least three agencies. In the first place, philosophy tended to destroy belief in the gods. The philosophic criticism of the existing religion was partly theoretical and partly ethical. The theoretical criticism arose especially through the search for a unifying principle operative in the universe. If the manifold phenomena of the universe were all reduced to a single cause, the gods might indeed still be thought of as existing, but their importance was gone. There was thus a tendency either toward monotheism or else toward some sort of materialistic monism. But the objections which philosophy raised against the existing polytheism were ethical as well as theoretical. The Homeric myths were rightly felt to be immoral; the imitation of the Homeric gods would result in moral degradation. Thus if the myths were still to be retained they could not be interpreted literally, but had to be given some kind of allegorical interpretation.