 In order for some proposed principle or rule, X, to meet the test of public reason, do the reasons or arguments that justify X need to be shared by all members of the constituency of justification, or can X meet the test of public reason by being justified to different people by appeal to different arguments? This is a question about the structure of public reason, in particular, about whether that structure must involve a kind of consensus, or whether it can allow different people to converge on the same rule or principle for entirely different reasons (D’Agostino 1996, 30–31; Nagel 1987, 218–219).