Understanding human history in the millennia following the Agricultural Revolution boils down to a single question: how did humans organise themselves in masscooperation networks when they lacked the biological instincts necessary to sustain such networks? The short answer is that humans created imagined orders and devised scripts. These two inventions filled the gaps left by our biological inheritance.
Unfortunately, complex human societies seem to require imagined hierarchies and unjust discrimination.
Hierarchies serve an important function. They enable complete strangers to know how to treat one another without wasting the time and energy needed to become personally acquainted.
Most sociopolitical hierarchies lack a logical or biological basis—they are nothing but the perpetuation of chance events supported by myths. That is one good reason to study history. If the divisions into blacks and whites or Brahmins and Shudras was grounded in biological realities—that is if Brahmins really had better brains than Shudras—biology would be sufficient for understanding human society. Since the biological distinctions between different groups of Homo Sapiens are in fact negligible, biology can’t explain the intricacies of Indian society or America racial dynamics. We can only understand those phenomena by studying the events, circumstances, and power relations that transformed figments of imagination into cruel—and very real—social structures.