I have answered the first central question by establishing that strict rational egoists cannot achieve efficient outcomes of trade in the absence of moral normative constraints. Economic efficiency requires morality. We now turn our attention to the second central question:

In this chapter, I determine and discuss the normative conditions for the achievement of Pareto-optimal equilibrium allocations of commodities.

It is important to note that Pareto-optimal equilibrium allocations of commodities are outcomes of social behavior. Analysts have traditionally assumed the consequences of coordinated behavior such as the absence of externalities and competitive behavior. But we have been looking closely at the presuppositions of coordinated behavior. We must not lose sight of the fact that efficient outcomes of trade are outcomes of coordinated social behavior. In this chapter, I specify in detail the elements of a system of social order that coordinates social behavior. In short, I specify the moral conditions of economic efficiency.

Concentrating, as we have, on rules, incentives, and individual behavior can diminish our tacit awareness of the social dimension of trade. Trade is social behavior consisting in a set of exchanges or series of exchanges. A set or series of exchanges that results in efficient outcomes is norm-guided social behavior. Both coordination norms and collective action norms guide a group of agents toward the achievement of Pareto-optimal equilibrium allocations of commodities.