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An analysis and rebuttal of Jaegwon Kim's reasons for taking nonreductive physicalism to entail the causal irrelevance of mental features to physical phenomena, particularly the behaviour of human bodies.

Throughout the 1990s, Jaegwon Kim developed a line of argument that what purport to be nonreductive forms of physicalism are ultimately untenable, since they cannot accommodate the causal efficacy of mental states. His argument has received a great deal of discussion, much of it critical. We believe that, while the argument needs some tweaking, its basic thrust is sound. In what follows, we will lay out our preferred version of the argument and highlight its essential dependence on a causal-powers metaphysic, a dependence that Kim does not acknowledge in his official presentations of the argument.i We then discuss two recent physicalist strategies for preserving the causal efficacy of the mental in the face of this sort of challenge, strategies that (ostensibly) endorse a causal powers metaphysics of properties while offering distinctive accounts of the physical realization of mental properties. We argue that neither picture can be satisfactorily worked out, and that seeing why they fail strongly suggests that nonreductive physicalism and a causal powers metaphysic are not compatible, as our original argument contends. Since we also believe that robust realism concerning mental causation should not be abandoned, we take the argument of this paper to strongly motivate an account on which the mental is unrealized by and ontologically emergent from the physical. In a final section, we sketch what an ontologically emergentist account of the mental might look like.

Given some reasonable assumptions concerning the nature of mental causation, non-reductive physicalism faces the following dilemma. If mental events cause physical events, they merely overdetermine their effects (given the causal closure of the physical). If mental events cause only other mental events, they do not make the kind of difference we want them to. This dilemma can be avoided if we drop the dichotomy between physical and mental events. Mental events make a real difference if they cause actions. But actions are neither mental nor physical events. They are realized by physical events, but they are not type-identical with them. This gives us non-reductive physicalism without downward causation. The tenability of this view has been questioned. Jaegwon Kim, in particular, has argued that non-reductive physicalism is committed to downward causation. Appealing to the nature of actions, I will argue that this commitment can be avoided.

Mental causation, though a forceful intuition embedded in our commonsense psychology, is difficult to square with the rest of commitments of physicalism about the mind. Advocates of mental causation have found solace in the causal inheritance principle, according to which the mental properties of mental states share the causal powers of their physical counterparts. In this paper, I present a variety of counterarguments to causal inheritance and conclude that the requirements for causal inheritance are stricter than what standing versions of said principle imply. In line with this, physicalism may be destined to epiphenomenalism unless multiple realizability turns out false.

Over the past few decades, Jaegwon Kim has argued that non-reductive physicalism is an inherently unstable position. In his view, the most serious problem is that non-reductive physicalism leads to type epiphenomenalism—the causal inefficacy of mental properties. Kim suggests that we can salvage mental causation by endorsing functional reduction. Given the fact that Kim’s goal in formulating functional reduction is to provide a robust account of mental causation it would be surprising if his position implies eliminativism about mental properties or leads to a view that is similar to one of the versions of non-reductive physicalism that he criticizes. We will show that depending on how certain key claims are interpreted, there are reasons for thinking functional reduction has these implications, in which case either Kim fails to provide a robust account of mental causation or there is reason to suspect that some of his criticisms of non-reductive physicalism are misguided.

This paper is about a puzzle which lies at the heart of contemporary physicalist theories of mind. On the one hand, the original motivation for physicalism was the need to explain the place of mental causation in the physical world. On the other hand, physicalists have recently come to see the explanation of mental causation as one of their major problems. But how can this be? I-low can it be that physicalist theories still have a problem explaining something which their physicalism was intended to explain in the first place? lf physicalism is meant to be an explanation of mental causation, then why should it still face the problem of mental causation? Disentagling this puzzle will cast light both on the recent mental causation debate and on physicalism itself. We can make a broad distinction between those forms of physicalism which identify mental and physical items and those which claim that there is some weaker relation of ’constitution’ between the mental and the physical. This latter view is now the orthodox version of physicalism. I shall argue that the problem of mental causation is only a problem for this orthodox physicalism, and not for identity theories. ln itself, this is not a particularly unusual claim. But I shall also argue that the real lesson of the mental causation debate is that orthodox physicalism is either unstable or unmotivated. It is unstable because (unlike the identity theories) it cannot reconcile mental causation with its other physicalist assumptions. It is unmotivated because in attempting to solve this mental causation problem, orthodox physicalism typically abandons one (or more) of the assumptions which form part of the original motivation for physicalism. To establish this, I need to explain (a) the nature of the arguments for physicalism, (b) the problem of mental causation, and (c) the standard solutions to the problem. These three tasks will form the main substance of this paper. But first I need to make some preliminary remarks about physicalism..

Orthodox physicalism has a problem with mental causation. If physics is complete and mental events are not identical to physical events (as multiple-realisation arguments imply) it seems as though there is no causal work for the mental to do. This paper examines some recent attempts to overcome this problem by analysing causation in terms of counterfactuals or conditional probabilities. It is argued that these solutions cannot simultaneously capture the force of the completeness of physics and make room for mental causation.

A well-known ``overdetermination''argument aims to show that the possibility of mental causes of physical events in a causally closed physical world and the possibility of causally relevant mental properties are both problematic. In the first part of this paper, I extend an identity reply that has been given to the first problem to a property-instance account of causal relata. In the second, I argue that mental types are composed of physical types and, as a consequence, both mental and physical types may be causally relevant with respect to the same physical effect, contrary to the overdetermination argument. In further sections, I argue that mental types have causal powers, consider some objections and reject an alternative version of part-whole physicalism. Throughout I assume that causal relata are tropes and property types are classes of tropes.

Stephen Yablo has recently argued for a novel solution to the mental causation problem: the mental is related to the physical as determinables are related to determinates; determinables are not causal rivals with their determinates; so the mental and the physical are not causal rivals. Despite its attractions the suggestion seems hard to accept. In this paper I develop the idea that mental properties and physical properties are not causal rivals. Start with property dualism, supervenience, multiple realizability, and the claim that no more than one supervenience base for a mental property can be had by a single instance of the mental property. Then a probabilistic account of causation will be unable to certify either mental properties or physical properties as causal factors for effect types. I suggest that this shows that we should not count mental properties as causal rivals with physical properties.

Keywords: action, dualism, functionalism, materialism, physicalism Contents l. What is mental causation? 2. History 3. Mental causation as a problem for dualism 4. Mental causation as a problem for physicalism 5. Mental causation and cognitive science..