Abstract

Street’s Darwinian dilemma claims that anti-realist theories are more parsimonious explanations of moral evaluative attitudes. Anti-realists claim we have evaluative attitudes because having them was evolutionarily beneficial. Unlike the realist, the anti-realist does not need to appeal to moral facts to explain evaluative attitudes. Such parsimony is not the only way a theory can be simpler. Realists may appeal to theory unity to respond to the anti-realist’s dilemma. Unity is when the same account explains more observed phenomena. Realists may do this by using a tracking account to explain both moral and epistemic evaluative attitudes. Some anti-realists conversely present a more disunified account. Such theories use a tracking account to explain epistemic evaluative attitudes but an adaptive link account to explain moral evaluative attitudes. Compared to such an account the realist’s single account of both epistemic and moral evaluative attitudes is more unified and may be simpler. Anti-realists defending such a position must explain why their ontological parsimony is preferable to the realist’s unity. However, there is no agreement as to how to go about this. Unless this can be done, this complicates Street’s anti-realist claim on the second horn. Further, this implicates other similar anti-realist accounts claiming simplicity over realists. However, through an objection, we will show the anti-realist who claims to explain all evaluative attitudes with an adaptive link account possesses the simplest theory. Determining which simplicity comparison is the most useful will require arguing for the most plausible realist or anti-realist account. I will avoid doing this and will only mention the various measures of simplicity they comparatively do well or poorly on. Whatever the most plausible position is, my paper will inform it as to how well it fares in terms of simplicity when compared to either the opposing realist or anti-realist.