Though in India old ideas persist with unusual vitality, still even there they can live only if they either develop or gather round them new accretions. As one of the religions of India, Buddhism was sensitive to the general movement of Indian thought, or rather it was a part of that movement. We see as clearly in Buddhist as in non-Buddhist India that there was a tendency to construct philosophic systems and another tendency to create deities satisfying to the emotions as well as to the intellect and yet another tendency to compose new scriptures. But apart from this parallel development, it becomes clear after the Christian era that Buddhism is becoming surrounded by Hinduism. The influence is not indeed one-sided: there is interdependence and interpenetration but the net result is that the general Indian features of each religious period overpower the specially Buddhist features and in the end we find that while Hinduism has only been profoundly modified Buddhism has vanished.
If we examine the Pali Pitakas, including the heresies mentioned in the Kathavatthu, we find that they contain the germs of many Mahayanist ideas. Thus side by side with the human portrait of the Buddha there is the doctrine that he is one in a series of supernatural teachers, each with the same life-history, and this life is connected with the whole course of nature, as is shown by the sympathetic earthquakes which mark its crises. His birth is supernatural and had he willed it he could have lived until the end of the present Kalpa.[171] So, too, the nature of a Buddha when he is released from form, that is after death, is deep and unfathomable as the ocean.[172] The Kathavatthu condemns the ideas (thus showing that they existed) that Buddhas are born in all quarters of the universe, that the Buddha was superhuman in the ordinary affairs of life, that he was not really born in the world of men and that he did not preach the Law himself. These last two heresies are attributed by the commentary to the Vetulyakas who are said to have believed that he remained in the Tushita heaven and sent a phantom to preach on earth. Here we have the rudiments of the doctrine afterwards systematized under the name of the three bodies of Buddha. Similarly though Nirvana is regarded as primarily an ethical state, the Pali Canon contains the expression Nirvanadhatu and the idea[173] that Nirvana is a sphere or realm (ayatanam) which transcends the transitory world and in which such antitheses are coming and going,