 An even more fundamental worry arising out of the causal inertness of moral properties, given non-naturalism, is how our words and concepts manage so much as to be about those properties.  Certainly on a causal theory of reference it would be very hard indeed to explain how our moral words and concepts could refer to such sui generis moral properties.  This worry about what is sometimes called “semantic access” has only recently started to get the attention it deserves – see Wedgwood 2009 and Enoch 2011.  Matti Eklund develops this worry about reference determination in an especially powerful way (Eklund 2017).  He argues that a constraint on a plausible theory of reference determination must ensure that what he calls the “normative role” (roughly, the practical role played by normative predicates in our deliberations about what to do) must be sufficient to determine a unique non-natural referent.  Otherwise, it will be possible for there to be other communities to use apparently normative predicates to refer to different non-natural properties.  This constraint is very far from trivial to satisfy; Eklund suggests that Wedgwood’s theory is unique in trying to meet it.  By contrast, a form of non-naturalism like the one defended by Cuneo and Shafer-Landau (Cuneo and Shafer Landau 2014) seems ill-suited to meeting this constraint.   On their view, the reference of moral terms and concepts is fixed, in part by more substantive “fixed points” which would seem to go beyond the mere normative role that Eklund has in mind.  Although Eklund admits the worry he has is in some ways ineffable, it seems like there ought to be some way in which the properties picked out by our normative predicates are the “right” ones to care about.  The reason Eklund’s worry is perhaps ineffable is that we presumably must index “right” in “right ones to care about” either to what we mean by “right” or by what some deviant possible community means by “right,” but neither seems to capture the intended worry.  Eklund notes the obvious analogies with the “Moral Twin Earth” objection to naturalism. 