My goal in this paper is to show that naturalists cannot reasonably endorse moral realism. My argument will come in two parts. The first part aims to show that any plausible and naturalistically acceptable argument in favor of belief in objective moral properties will appeal in part to simplicity considerations (broadly construed)—and this regardless of whether moral properties are reducible to non-moral properties. The second part argues for the conclusion that appeals to simplicity justify belief in moral properties only if (...) either those properties are not objective or something like theism is true. Thus, if my argument is sound, naturalists can reasonably accept moral realism only if they are prepared to accept something like theism. But, as will become clear, naturalists can reasonably accept theism or something like it only if belief in some such doctrine is justified by the methods of science. For present purposes, I’ll assume (what I think virtually every naturalist will grant) that belief in theism and relevantly similar doctrines is not justified by the methods of science. Thus, I will conclude that naturalists cannot reasonably accept moral realism. (shrink)

Realism about material objects faces a variety of epistemological objections. Recently, however, some realists have offered new accounts in response to these long-standing objections; many of which seem plausible. In this paper, I raise a new objection against realism vis-à-vis how we could empirically come to know mind-independent essential properties for objects. Traditionally, realists hold kind-membership and persistence as bound together for purposes of tracing out an object’s essential existence conditions. But I propose kind-membership and persistence for objects can conceptually (...) come apart and function epistemologically distinctly from one another—in which case the usual reliance by realists on an assumption of persistence to determine kind-membership conditions is unjustified. Thus, present realist attempts to explain how empirical detection of mind-independent essential properties for objects could possibly occur inevitably results in circularity. The charge against the realist is to explain why we don’t have to first discover persistence conditions for an object before we can ascertain kind-membership conditions for an object. If no answer is forthcoming, then it seems the weight of the epistemological objection to realism is back in full force. (shrink)