  Now, it follows that for something to be able to claim legitimate authority, it must be of the kind of thing capable of claiming it, namely, capable of fulfilling such a mediating role. What kinds of things can claim legitimate authority? There are at least two such features necessary for authority-capacity: First, for something to be able to claim legitimate authority, it must be the case that its directives are identifiable as authoritative directives, without the necessity of relying on those same reasons which the authoritative directive replaces. If this condition is not met, namely, if it is impossible to identify the authoritative directive as such without relying on those same reasons the authority was meant to rely on, then the authority could not fulfill its essential, mediating role. In short, it could not make the practical difference it is there to make. Note that this argument does not concern the efficacy of authorities. The point is not that unless authoritative directives can be recognized as such, authorities could not function effectively. The argument is based on the rationale of authorities within our practical reasoning. Authorities are there to make a practical difference, and they could not make such a difference unless the authority’s directive can be recognized as such without recourse to the reasons it is there to decide upon. In other words, it is pointless to have an authoritative directive if, in order to discover what the directive is, you have to engage in the same reasoning that reliance on the directive is supposed to replace. Secondly, for something to be able to claim legitimate authority, it must be capable of forming an opinion on how its subjects ought to behave, distinct from the subjects’ own reasoning about their reasons for action; authority requires some authorship.