This cosmological interpretation of the tales referring to Hades had a more powerful influence than the moral allegory which did too much violence to tradition in claiming to make our earthly life the mythological hell. The doctrine that the _Inferi_ were in the atmosphere was adopted by Stoicism at least from the time of Posidonius and was therefore widely believed from the end of the Roman Republic onwards. Even the mysteries, which first kept alive the belief in a subterranean kingdom of the infernal gods, did not escape the influence of these new ideas and were brought to adapt their esoteric teaching to them.[196] The transformation of ancestral beliefs by this theology cannot today be better apprehended than from the sixth book of the Aeneid. Virgil, when he relates the descent of Aeneas into the abode of the shades, is inspired by the _Nekyia_ of the Odyssey and other poetic tales. He remains apparently faithful to mythological and literary tradition, retaining the conventional decoration, the unvarying geography of the infernal kingdom; but he does not admit the literal truth of these beliefs of an earlier time; he is aware of the figurative sense given by the philosophers to the old fables of Hades. At the risk of seeming to contradict himself, he recalls this learned eschatology—the purification, the ascension and the transmigration of souls—in connection with what might have been no more than the story of a marvellous journey to the country of the dead. The unity of the conception and the composition is the less seriously compromised because it was believed that the ancient poets themselves had wished to indicate these truths in their verses under the veil of allegory. The descent to the nether world has therefore a much loftier bearing in Virgil than a mere embellishment. It is the expression of a conviction or at least a hope, not only a brilliant fiction based on an old poetic theme. * * * * *