Andrew Lister’s post is the first in our four-part series on “Just Wages,” which will be running this month.
Gregory Mankiw argues that those who are more productive should get a higher income not only as an incentive, but because this income is rightfully theirs (295). In a competitive market, factors of production are paid the value of their marginal product (32), which is the change in output associated with adding an extra unit of that input. Firms hire workers of a given type up to point at which the revenue the firm gains from hiring an additional worker is equal to the cost of that worker. Thus, in competitive equilibrium “each person’s income reflects the value of what he contributed to society’s production of goods and services.” In this way, the theory of “just deserts” gives “a new normative interpretation” to the economic theory of competitive equilibrium (295).
Joe Heath responds that wages in a competitive market aren’t intrinsically fair. Wage-setting is not a unidirectional process from unequal skill and effort to unequal contribution to unequal wages. Where workers of a given skill-level are more abundant, they will be cheaper, and so hired for lower-value tasks, and so less productive even if equally skilled and diligent. The rationale for pricing labour according to supply and demand is that it directs people’s talents to where they can best be used, generating prosperity that can benefit everyone. As Heath says, “[t]he market has one job to do, and it does that job very well [allocating resources efficiently]. Producing ‘just’ wages, however, is not that job” (31).
