Russellian Physicalism, Bare Structure, and Swapped Inscrutables

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.