Chinese philosophy began in the sixth century BCE with social and political philosophy as a response to the collapse of traditional bronze-age feudal society (Shang and Zhou dynasties). As the loyalty of the nobility to the Zhou kings began to give way to the realpolitik of sheer military might, dozens of small kingdoms vied with one another for imperial domination in what became known appropriately as the Warring States period (475–221 BCE). This strife ended when the kingdom of Qin finally conquered the last of its competitors to unite, for the first time, the many warring states into a single military, imperial empire.

The problem was how to unify and rule such a heterogeneous collection of different ethnic groups. Into this breach came China's first philosophers. In the feudal period, social custom was maintained by etiquette as practiced and maintained by the aristocrats...