(1) In his recent paper, “Justice as Fairness: Political not Metaphysical,” John Rawls makes use of a footnote to disown what to many readers must have seemed one of the most striking and original underlying ideas of his theory of justice, that it “is a part, perhaps the most significant part, of the theory of rational choice.” That Rawls should issue this disclaimer indicates, at least in my view, that he has a much clearer understanding of his theory, and its relationship to rational choice than he did at the time that he wrote A Theory of Justice. As I note in Morals by Agreement (pp.4–5), Rawls does not show that principles of justice are principles of rational choice. Hence, in appropriating the idea, I can claim diat I am undertaking a pioneering enterprise. No doubt Thomas Hobbes would have undertaken it had the resources of the theory of rational choice been at his disposal, but I do not intend to pursue counterfactuals in a search for historical antecedents. Moral theory as rational choice theory is, I claim, a new venture.