  The argument is illustrated by the “Moral Twin Earth” thought experiment. Moral Twin Earth is a planet whose inhabitants speak a language which is similar to ours in that it includes the moral terms “good”, “right”, “wrong” and so on. Moreover, the social and psychological roles those terms play in their communities overlap with those they play in our communities. We may imagine, for example, that they figure in similar ways in their deliberations and discussions about how to act, and that the inhabitants are, like us, in general motivated to act and avoid acting in ways they classify as “right” and “wrong”, respectively. A further stipulation—a crucial one in this context—is that the inhabitants’ uses of the pertinent terms are causally regulated by different properties than those that regulate our uses of them. Thus, their use of “right” is regulated by the property actions have by satisfying certain deontological requirements, while ours is regulated by the consequentialist property actions have when maximizing happiness. Given that stipulation, “right” does not, on Boyd’s account, refer to the same property for us and for them. So, again, the disputes we might have with them about how to apply “right” need not reflect any conflicts of belief. What Horgan and Timmons suggest, however, in a way which mirrors Hare’s argumentation, is that it would still be plausible to construe our disputes with them regarding how to apply it as genuine moral disagreements, in virtue of the overlap in social and psychological roles (for a different critique of Boyd’s approach, see Schroeter and Schroeter 2013).