Non-naturalism, the supervenience challenge, higher-order properties, and trope theory

Non-naturalist realism is the view that normative properties are unique kind of stance-independent properties. It has been argued that such views fail to explain why two actions that are exactly alike otherwise must also have the same normative properties. Mark Schroeder and Knut Olav Skarsaune have recently suggested that non-naturalist realists can respond to this supervenience challenge by taking the primary bearers of normative properties to be action-kinds. This paper develops their response in two ways. Firstly, it provides additional motivation for the previous claim about the bearers of normative properties by drawing from the work of H.A. Prichard. Secondly, and more importantly, it formulates a plausible metaphysical framework based on the contemporary trope theory to explain why action-kinds would have their second-order properties, including their normative properties, necessarily.