I try to ground my philosophy in science and naturalism. So I'd say that human nature evolves out of animal nature. In "Some Basics of Cynical Sociology," I show how the default social order of leaders, followers, and outsiders makes for the dominance hierarchies found throughout the animal kingdom and in more rationalized forms in our societies. I show also how these power dynamics make for moral differences, as the dominators are naturally corrupted by their privileged positions. That's where the predators and parasites come from, from sociobiological strategies of succeeding in the wild.