Twenty-Five On

This article updates Morals by Agreement. It distinguishes two opposed conceptions of deliberative rationality- maximization and Pareto- optimization. It defends the latter. The constrained maximizers of Morals by Agreement are replaced by rational cooperators. They do not bargain but reach agreement on the principle of maximin proportionate gain, which is a relabeling of maximin relative benefit. The contractarian test, of the acceptability of social arrangements and norms, is introduced, and the Lockean proviso assumes an enhanced role as a cornerstone of rational cooperation. But questions about the force and rationale of the proviso remain.