First, thanks for another very informative article.

Farming (and pastoralism) did bring about permanent surplus: always having more than needed for survival. Surplus encouraged the development of hierarchical, inegalitarian social structures, even slavery. It gave a material benefit to having power over others that living in permanent survival mode as a group (i.e., foragers) did not. As I understand it, in parts of what Europeans would call the "New World" groups were developing social systems--even permanent settlements--that incorporated permanent surplus without tyranny/slavery, but that, too, was a victim of the arrival of Europeans.