The connection between Rawls and Buchanan is examined in the light of the shared influence of Knight. Rawls’s annotations of Knight’s Ethics of Competition support this claim. The chapter returns to Buchanan’s 17 October 1960 letter to Gordon, of the Ford Foundation, in which Buchanan describes the key difference between the Virginia and the orthodox approaches. Buchanan defends markets on the basis of consensus attained through a long process of democratic discussion. The orthodox tradition defends market exchange axiomatically via efficiency criteria. The problem is what to do about third-party effects. How do we know if they are negligible? A Virginia School answer is not to look at physical reality but at consensus. This offers a way to endogenize what is otherwise assumed away.