The Grounding Argument against Non-reductive Moral Realism

Abstract

The supervenience argument against non-reductive moral realism threatens to rule out the existence of irreducibly normative properties by establishing that for every normative property there is a corresponding non-normative property that is necessarily co-extensive with it. This chapter identifies a hyperintensional analogue of the supervenience argument that threatens non-reductionism even within a hyperintensional setting by establishing that for every normative property there is a corresponding non-normative property that has the very same grounds and is, accordingly, hyperintensionally equivalent. It is then argued that non-reductionism can nevertheless be salvaged by distinguishing the different grounding relations that are involved in grounding the normative property and the corresponding non-normative property. Non-reductionist versions of moral realism thus turn out to be committed to there being irreducibly different grounding relations.