The Hindu reaction against Buddhism became apparent under the Gupta dynasty but Mahayanism in its use of Sanskrit and its worship of Bodhisattvas shows the beginnings of the same movement. The danger for Buddhism was not persecution but tolerance and obliteration of differences. The Guptas were not bigots. It was probably in their time that the oldest Puranas, the laws of Manu and the Mahabharata received their final form. These are on the whole text-books of Smârta Hinduism and two Gupta monarchs celebrated the horse sacrifice. But the Mahabharata contains several episodes which justify the exclusive worship of either Vishnu or Siva, and the architecture of the Guptas suggests that they were Vishnuites. They also bestowed favours on Buddhism which was not yet decadent, for Vasubandhu and Asanga, who probably lived in the fourth century, were constructive thinkers. It is true that their additions were of the dangerous kind which render an edifice top-heavy but their works show vitality and had a wide influence[23]. The very name of Asanga's philosophy—Yogâcârya—indicates its affinity to Brahmanic thought, as do his doctrines of Alayavijñâna and Bodhi, which permit him to express in Buddhist language the idea that the soul may be illumined by the deity. In some cases Hinduism, in others Buddhism, may have played the receptive part but the general result—namely the diminution of differences between the two—was always the same. The Hun invasions were unfavourable to religious and intellectual activity in the north and, just as in the time of Moslim inroads, their ravages had more serious consequences for Buddhism than for Hinduism. The great Emperor Harsha (†647), of whom we know something from Bâna and Hsüan Chuang, became at the end of his life a zealous but eclectic Buddhist. Yet it is plain from Hsiian Chuang's account that at this time Buddhism was decadent in most districts both of the north and south.