ancient writing’s main function was “to facilitate the enslavement of other human beings.”
Some productive hunter-gatherer societies reached the organizational level of chiefdoms, but none reached the level of states: all states nourish their citizens by food production.
Intensified food production and societal complexity stimulate each other, by autocatalysis.
it is much more difficult to understand human history than to understand problems in fields of science where history is unimportant and where fewer individual variables operate.