A grounding physicalist solution to the causal exclusion problem

Abstract

Remember how Kim (Philos Perspect 3:77-108, 1989, in: Heil and Mele (eds) Mental causation, Clarendon Press, Oxford, 1993b) used to argue against non-reductive physicalism to the effect that it cannot accommodate the causal efficacy of the mental? The argument was that if physicalists accept the causal closure of the physical, they are faced with an exclusion problem. In the original version of the argument, the dependence holding between the mental and the physical was cashed out in terms of supervenience. Due to the work or Fine (Philos Perspect 8:1-16, 1994) and others, we have since come to realize that modal notions are not well-suited to perform the work of properly characterizing dependence. As a consequence of this, an increasingly larger community of contemporary metaphysicians prefer to spell out mental-physical dependence in terms of a non-causal and non-reductive notion called grounding, which is intended to target a particular sort of metaphysical relation that takes us from ontologically less fundamental features of the world to that which is more fundamental. In this paper I join forces with those who think that this shift in focus is on the right track. More specifically, I will argue that the grounding physicalist can solve the exclusion problem in a way that is preferable to the supervenience-based nonreductive physicalist solution, as well as in a way that is compatible with the externalist picture of the mental.

Causal Exclusion and Grounding

“…Given the purposes of this section, I will concentrate only on how these issues are treated by those writers who have recently claimed that the nonreductivist can successfully meet the causal exclusion challenge by resorting to grounding. Hence, we will discuss here the arguments contained in Kroedel &Schulz 2016 andin Stenwall 2021. These authors, in line with many others, think that grounding is a relation which has the formal properties of a strict partial order. This is important, if we truly want to formulate Nonreductive Physicalism in terms of grounding.…”

A nonreductive physicalist libertarian free will

“…While the necessity relation comes in varying strengths, I shall follow nonreductive physicalist orthodoxy, according to which the necessity relation from P to A is metaphysically necessary (Tiehen 2018, 538;Kallestrup 2006, 473;Bennett 2003, 490). Some nonreductive physicalists prefer to emphasize other sorts of dependency relations between A and P, such as realization (Shoemaker 2007), constitution (Pereboom 2002), determinables (Yablo 1992), or, more recently, grounding (Kroedel and Schultz 2016;Stenwall 2020). I leave open these other possible relations, as they also share the core view that P metaphysically necessitates and determines A, and A depends upon some P, as articulated in Supervenience.…”