According to the prevalent Chinese view, nothing of importance was achieved during this period in north China in the intellectual sphere; there was no culture in the north, only in the south. This is natural: for a Confucian this period, the fourth century, was one of degeneracy in north China, for no one came into prominence as a celebrated Confucian. Nothing else could be expected, for in the north the gentry, which had been the class that maintained Confucianism since the Han period, had largely been destroyed; from political leadership especially it had been shut out during the periods of alien rule. Nor could we expect to find Taoists in the true sense, that is to say followers of the teaching of Lao Tz[)u], for these, too, had been dependent since the Han period on the gentry. Until the fourth century, these two had remained the dominant philosophies. What could take their place? The alien rulers had left little behind them. Most of them had been unable to write Chinese, and in so far as they were warriors they had no interest in literature or in political philosophy, for they were men of action. Few songs and poems of theirs remain extant in translations from their language into Chinese, but these preserve a strong alien flavour in their mental attitude and in their diction. They are the songs of fighting men, songs that were sung on horseback, songs of war and its sufferings. These songs have nothing of the excessive formalism and aestheticism of the Chinese, but give expression to simple emotions in unpolished language with a direct appeal. The epic of the Turkish peoples had clearly been developed already, and in north China it produced a rudimentary ballad literature, to which four hundred years later no less attention was paid than to the emotional world of contemporary songs. The actual literature, however, and the philosophy of this period are Buddhist. How can we explain that Buddhism had gained such influence?