This course will study what Greek thinkers, especially philosophers, said about inequality generally, and in particular about the status and treatment of enslaved people, non-Greeks (the so-called barbarians), and women. We will see that these thinkers, far from unreflectively accepting the status quo, were actively engaging with, challenging, or supporting the ideas that slaves are subhuman and that their enslavement is just; that Greeks are irreconcilably opposed to "barbarians;" and that men are naturally different from, and superior to, women. The last part of the course will briefly turn to the post-Classical reception of these ideas.