ABSTRACT
It is often thought that mental properties are higher-order properties not reducible to physical properties. And it's plausible to think that when a pain or a belief causes a bit of behavior, it does so in virtue of its first-order physical properties. Thus, there is no additional work for higher-order mental properties to do: they are epiphenomenal. In this chapter I examine this reasoning in some detail. I begin with some of the relevant metaphysical background on higher-order properties, focusing on second-order properties. I define such properties and survey some arguments for thinking they exist. I also motivate the thesis that mental properties are second-order. I then return to mental causation and defend the Exclusion Argument: second-order mental properties are not causally efficacious, as they are causally excluded by their first-order physical realizers. I conclude by sketching an alternative ontology in which there are no higher-order properties.
