Abstract

Frank Jackson has famously argued that there is no logical space for the view which understands moral properties as non-natural properties of their own unique kind. His argument is based on two steps: firstly, given supervenience and truth-aptness of moral claims, it is always possible to find a natural property which is necessarily co-instantiated with a given moral property, and secondly that there are no distinct necessarily co-instantiated properties. I argue that this second step of the argument must rely on a controversial nominalist view of properties. In contrast, if we accept universals or tropes, there is logical space also for non-natural moral properties even if they are necessarily co-instantiated with natural properties.