Kevin Morris

A physicalist holds, in part, that what properties are instantiated depends on what physical properties are instantiated; a physicalist thinks that mental properties, for example, are instantiated in virtue of the instantiation of physical “realizer” properties. One issue that arises in this context concerns the relationship between the “causal powers” of instances of physical properties and instances of dependent properties, properties that are instantiated in virtue of the instantiation of physical properties. After explaining the significance of this issue, I evaluate two core lines of thought that have been advanced in favor of Subset Inheritance, the view that instances of dependent properties typically have some, but not all, of the powers of physical realizers, and do not have any powers that are not also powers of physical realizers. The first argument that I address turns on our intuitive reactions to certain cases; the second appeals to the phenomenon of multiple realization. I argue that neither line of thought succeeds, and thus that insofar as we grant that an instance of a dependent property inherits some of the powers of its physical realizer, defenders of subset inheritance have not provided a compelling reason to think that it will not inherit all of the powers of its physical realizer

This paper discusses and evaluates a recent argument for the conclusion that an attractive variety of Russellian monism ought to be regarded as a form of physicalism. According to this line of thought, if the Russellian’s “inscrutable” properties are held to ground not only experience, but also the physical structure of the world—and in this sense are not “experience-specific”—they thereby have an unproblematic place in physicalist metaphysics. I argue, in contrast, that there can be a sense in which the Russellian’s inscrutables are experience-specific in a way that a physicalist probably ought to find objectionable, even if they play some role other than grounding experience. This will be the case, I argue, if certain worlds are taken to be possible, as they sometimes have: worlds of “bare structure” and worlds with what might be called “swapped inscrutables”. In this way, I claim that accepting certain possibilities has consequences for how one should understand the nature of the Russellian’s inscrutables and the place they have in physicalist metaphysics.

Defenders of the subset view of realization have claimed that we can resolve well-known worries about mental-physical causal overdetermination by holding that mental properties are subset realized by physical properties, that instances of subset realized properties are parts of physical realizers, and that part-whole overdetermination is unproblematic. I challenge the claim that the overdetermination generated by the subset view can be legitimated by appealing to more mundane part-whole overdetermination. I conclude that the subset view does not provide a unique solution to overdetermination worries.