An irresistible cycle seemed to operate, repeating patterns of the ancient world where civil strife and war brought disaster... I surmised that patte… - William Hardy McNeill

By the sixth century A.D., ...a distinctively Chinese Buddhist art had arisen, in which figures with Chinese dress and Chinese faces nonetheless continued to conform to Indian conventions of gesture and ornament.

Details of early domestications remain unclear. One must assume a process of mutual accommodation between humanity and various domesticable species. This involved rapid and sometimes far-reaching change in the biological character of domesticated plants and animals as a result of both accidental and deliberate selection for particular traits. Conversely, one can assume that a radical, if rarely deliberate, selection among human beings occurred as well. Individuals who refused to submit to laborious routines of farming, for instance, must often have failed to survive, and those who could not or would not save seed for next year's planting, and instead ate all they had, were quickly eliminated from communities that become dependent upon annual crops.

Religious history also offers another striking parallel between Rome and China. The Buddhist faith began to penetrate the Han empire in the first century A.D., and soon won converts in high places. Its period of official dominance in court circles extended from the third to the ninth centuries A.D. This obviously parallels the successes that came to Christianity in the Roman empire during the same period.