The Importance of Infra-Marginal Payment

With economies of scale, division of labor, there's a sense in which even though everybody is being paid their marginal product, we're all better off if there's more of us than we all cooperate. That doesn't change the facts that we can all be better off if more people enter the labor force. And one way of looking at it is the difference between infra-marginal and marginal payment for workers.