A Theory on the Causation of Moral Social Advancement

Part of an ongoing conversation:

"Basically, the state of mankind is advanced by the natural inclination of people to combine, trade, and cooperate to achieve greater and more difficult ends than they would be able to achieve separately... The failure or retardation of moral social advancement, therefore, can be attributed to an inability to perceive potential benefits."

A peculiar and droll theory, but I know of no evidence to support it. The theory I hold has the advantage of being supported...