 Authority is effective, on this view, if it gets people to act on the reasons it generates. The difference between effective and legitimate authority, on Raz’ view, is that the former merely purports to change the reasons that apply to others, while legitimate authority actually has the capacity to change these reasons. Legitimate authority satisfies what Raz calls the pre-emption thesis: “The fact that an authority requires performance of an action is a reason for its performance which is not to be added to all other relevant reasons when assessing what to do, but should exclude and take the place of some of them” (Raz 1988: 46). (There are limits to what even a legitimate authority can rightfully order others to do, which is why it does not necessarily replace all relevant reasons.) 