Taking realization seriously: no cure for epiphobia

The realization relation that allegedly holds between mental and physical properties plays a crucial role for so-called non-reductive physicalism because it is supposed to secure both the ontological autonomy of mental properties and, despite their irreducibility, their ability to make a causal difference to the course of the causally closed physical world. For a long time however, the nature of realization has largely been ignored in the philosophy of mind until a couple of years ago authors like Carl Gillett, Derk Pereboom, or Sydney Shoemaker proposed accounts according to which realization is understood against the background of the so-called ‘causal theory of properties’. At least partially, the hope was to solve the problem of mental causation, in particular the kind of causal exclusion reasoning made famous by Jaegwon Kim, in a way acceptable to non-reductive physicalists. The paper asks whether a proper explication of the realization relation can indeed help explain how physically realized mental properties can be causally efficacious in the causally closed physical world and argues for a negative answer: it is important for the non-reductive physicalist to understand what exactly the realization relation amounts to, but it does not solve the problem of mental causation.     

The Exclusion Problem Meets the Problem of Many Causes

In this paper I develop a novel response to the exclusion problem. I argue that the nature of the events in the causally complete physical domain raises the “problem of many causes”: there will typically be countless simultaneous low-level physical events in that domain that are causally sufficient for any given high-level physical event (like a window breaking or an arm raising). This shows that even reductive physicalists must admit that the version of the exclusion principle used to pose the exclusion problem against non-reductive physicalism is too strong. The burden is on proponents of the exclusion problem to provide a reason to think that any qualifications placed on the exclusion principle will solve the problem of many causes while ruling out causation by irreducible mental events.     

Causal Exclusion and Causal Autonomism

The causal exclusion problem is often considered as one of the major difficulties for which non-reductive physicalists have no easy solution to offer. Some non-reductive physicalists address this problem by arguing that mental properties are to some extent causally autonomous. If this is the case, then mental properties will not be causally excluded by their physical realizers because causation, in general, is a relation between properties of the same level. In this paper, I argue that the response from causal autonomy cannot be successful for two reasons. First, it does not offer a satisfactory explanation for how mental particulars can have causal efficacy in a non-reductive physicalist framework. Second, the causal considerations underpinning this response do not really support the conclusion that mental properties are causally autonomous.     

Emerging from the causal drain

For over 20 years, Jaegwon Kim’s Causal Exclusion Argument has stood as the major hurdle for non-reductive physicalism. If successful, Kim’s argument would show that the high-level properties posited by non-reductive physicalists must either be identical with lower-level physical properties, or else must be causally inert. The most prominent objection to the Causal Exclusion Argument—the so-called Overdetermination Objection—points out that there are some notions of causation that are left untouched by the argument. If causation is simply counterfactual dependence, for example, then the Causal Exclusion Argument fails. Thus, much of the existing debate turns on the issue of which account of causation is appropriate. In this paper, however, I take a bolder approach and argue that Kim’s preferred version of the Causal Exclusion Argument fails no matter what account one gives of causation. Any notion of causation that is strong enough to support the premises of the argument is too strong to play the role required in the logic of the argument. I also consider a second version of the Causal Exclusion Argument, and suggest that although it may avoid the problems of the first version, it begs the question against a particular form of non-reductive physicalism, namely emergentism.     

Excluding exclusion: the natural(istic) dualist approach

The exclusion problem for mental causation is one of the most discussed puzzles in the mind–body literature. There has been a general agreement among philosophers, especially because most of them are committed to some form of physicalism, that the dualist cannot escape the exclusion problem. I argue that a proper understanding of dualism – its form, commitments, and intuitions – makes the exclusion problem irrelevant from a dualist perspective. The paper proposes a dualist approach, based on a theory of event causation, according to which events are medium-grained, namely parsed into mental and physical property components. A theory of contrastive mental causation is built upon this theory of events, for which the problem of exclusion does not arise.     

Intralevel mental causation

This paper identifies and critiques a theory of mental causation defended by some proponents of nonredutive physicalism that I call “intralevelism.” Intralevelist theories differ in their details. On all versions, the causal outcome of the manifestation of physical properties is physical and the causal outcome of the manifestation of mental properties is mental. Thus, mental causation on this view is intralevel mental to mental causation. This characterization of mental causation as intralevel is taken to insulate nonreductive physicalism from some objections to nonreductive physicalism, including versions of the exclusion argument. This paper examines some features of three recent versions of intralevelism defended by John Gibbons, Markus Schlosser, and Amie Thomasson. This paper shows that the distinctive problems faced by these three representative versions of intralevelism suggest that the intralevelist strategy does not provide a viable solution to the exclusion problem.     

Can determinable properties earn their keep?

Sydney Shoemaker’s ‘Subset Account’ offers a new take on determinable properties and the realization relation as well as a defense of non-reductive physicalism from the problem of mental causation. At the heart of this account are the claims that (1) mental properties are determinable properties and (2) the causal powers that individuate a determinable property are a proper subset of the causal powers that individuate the determinates of that property. The second claim, however, has led to the accusation that the effects caused by the instantiation of a determinable property will also be caused by the instantiation of the determinates of that property—so instead of solving the problem of mental causation, the Subset Account ends up guaranteeing that the effects of mental properties (and all other types of determinable property) will be causally overdetermined! In this paper, I explore this objection. I argue that both sides in this debate have failed to engage the question at the heart of the objection: Given that both a determinable property and its determinates have the power to cause some effect (E), does it follow that both will actually cause E when the relevant conditions obtain? To make genuine progress towards answering this question, we need to take a serious look at the metaphysics of causation. With the debate properly reframed and issues about the metaphysics of causation front and center, I explore the question of whether the Subset Account is doomed to result in problematic causal overdetermination.     

The Inherent Empirical Underdetermination of Mental Causation

It has become a popular view among non-reductive physicalists that it is possible to devise empirical tests generating evidence for the causal efficacy of the mental, whereby the exclusion worries that have haunted the position of non-reductive physicalism for decades can be dissolved once and for all. This paper aims to show that these evidentialist hopes are vain. I argue that, if the mental is taken to supervene non-reductively on the physical, there cannot exist empirical evidence for its causal efficacy. While causal structures without non-reductive supervenience relations can be conclusively identified in ideal discovery circumstances, it is impossible, in principle, to generate evidence that would favour models with mental causation over models without. Ascribing causal efficacy to the mental, for the non-reductive physicalist, is a modelling choice that must be made on the basis of metaphysical background theories or pragmatic maxims guiding the selection among empirically indistinguishable models.     

Part-Whole Physicalism and 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.     

Dualist Mental Causation and the Exclusion Problem

The paper argues that dualism can explain mental causation and solve the exclusion problem. If dualism is combined with the assumption that the psychophysical laws have a special status, it follows that some physical events counterfactually depend on, and are therefore caused by, mental events. Proponents of this account of mental causation can solve the exclusion problem in either of two ways: they can deny that it follows that the physical effect of a mental event is overdetermined by its mental and physical causes, or they can accept that the physical effect is overdetermined but claim that this is unproblematic because the case is sufficiently dissimilar to prototypical cases of overdetermination.     

William James on emotion and intentionality

In my reply I focus on three topics: the usefulness of Searle’s physical analogies for understanding the relationship between higher-level mental properties and lower-level physical properties, the question of overdetermination and the causal efficacy of unconscious intentional states. I argue that Searle’s reply does not refute my arguments against his analogies, while concerns about overdetermination are only taken away because his reply shows that there is no genuine unconscious mental causation in his view. That makes it hard to understand how he can maintain at the same time that we follow rules unconsciously.     

Neural Synchrony and the Causal Efficacy of Consciousness

The purpose of this paper is to address a well-known dilemma for physicalism. If mental properties are type identical to physical properties, then their causal efficacy is secure, but at the cost of ruling out mentality in creatures very different to ourselves. On the other hand, if mental properties are multiply realizable, then all kinds of creatures can instantiate them, but then they seem to be causally redundant. The causal exclusion problem depends on the widely held principle that realized properties inherit their causal powers from their realizers. While this principle holds for functional realization, it fails on a broader notion of realization that permits the realization of complex qualitative properties such as spatial and temporal patterns. Such properties are best seen as dependent powerful qualities, which have their causal roles in virtue of being the qualities they are, and do not inherit powers from their realizers. Recent studies have identified one such property—neural synchrony—as a correlate of consciousness. If synchrony is also partially constitutive of consciousness, then phenomenal properties are both multiply realizable and causally novel. I outline a version of representationalism about consciousness on which this constitution claim holds.

     

Emergence and Causal Powers

This paper argues that the non-reductive monist need not be concerned about the ‘problem’ of mental causation; one can accept both the irreducibility of mental properties to physical properties and the causal closure of the physical. More precisely, it is argued that instances of mental properties can be causally efficacious, and that there is no special barrier to seeing mental properties whose instances are causally efficacious as being causally relevant to the effects they help to bring about. It is then shown that the causal relevance of mental properties is consistent with there being no downward causation, so the dilemma of ‘epiphenomenalism or reduction’ can be avoided. Non-reductive monism lives on as a viable position in the philosophy of mind.

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Two Kinds of Completeness and the Uses (and Abuses) of Exclusion Principles

I argue that the completeness of physics is composed of two distinct claims. The first is the commonly made claim that, roughly, every physical event is completely causally determined by physical events. The second has rarely, if ever, been explicitly stated in the literature and is the claim that microphysics provides a complete inventory of the fundamental categories that constitute both the causal features and intrinsic nature of all the events that causally affect the physical universe. After showing that these claims are distinct, I argue that they can be used to solve a difficulty with existing responses to the exclusion problem—namely, that these existing responses also undermine the powerful causal argument for physicalism. Recognizing that there are two kinds of completeness opens up room for the nonreductive physicalist to solve the exclusion problem while also endorsing a modified, cogent causal argument for a kind of physicalism compatible with her position.     

The Dispositional Nature of Phenomenal Properties

Topoi - According to non-reductive physicalism, mental properties of the phenomenal sort are essentially different from physical properties, and cannot be reduced to them. This being a quarrel...     

Determination,realization and mental causation

How can mental properties bring about physical effects, as they seem to do, given that the physical realizers of the mental goings-on are already sufficient to cause these effects? This question gives rise to the problem of mental causation (MC) and its associated threats of causal overdetermination, mental causal exclusion, and mental causal irrelevance. Some (e.g., Cynthia and Graham Macdonald, and Stephen Yablo) have suggested that understanding mental-physical realization in terms of the determinable/determinate relation (henceforth, ‘determination’) provides the key to solving the problem of MC: if mental properties are determinables of their physical realizers, then (since determinables and determinates are distinct, yet don’t causally compete) all three threats may be avoided. Not everyone agrees that determination can do this good work, however. Some (e.g., Douglas Ehring, Eric Funkhauser, and Sven Walter) object that mental-physical realization can’t be determination, since such realization lacks one or other characteristic feature of determination. I argue that on a proper understanding of the features of determination key to solving the problem of MC these arguments can be resisted.     

Supervenience Physicalism: Meeting the Demands of Determination and Explanation

Abstract

Non-reductive physicalism is currently the most widely held metaphysic of mind. My aim in this essay is to show that supervenience physicalism—perhaps the most common form of non-reductive physicalism—is not a defensible position. I argue that, in order for any supervenience thesis to ground a legitimate form of physicalism, it must yield the right sort of determination relation between physical and non-physical properties. Then I argue that non-reductionism leaves one without any explanation for the laws that are implied by supervenience theses that deliver this determination relation.     

A Nonreductivist Solution to Mental Causation

Nonreductive physicalism provides an appealing solution to the nature of mental properties. But its success as a theory of mental properties has been called into doubt by claims that it cannot adequately handle the problems of mental causation, as it leads either to epiphenomenalism or to thoroughgoing overdetermination. I argue that these apparent problems for the nonreductivist are based in fundamental confusion about causation and explanation. I distinguish two different types of explanation and two different relations to which they appeal: causation and determination. I argue that these types of explanation do not compete with one another, nor do these relations jointly result in overdetermination. In closing I develop a nonreductivist solution to mental causation which avoids both the hazards of epiphenomenalism and of overdetermination and so demonstrates a way to save nonreductive physicalism from the problems of mental causation.     

The Epistemic/Ontic Divide

A number of philosophers think that, while we cannot explain how the mind is physical, we can know that it is physical, nonetheless. That is, they accept both the explanatory gap between the mental and the physical and ontological physicalism. I argue that this position is unstable. Among other things, I argue that once one accepts the explanatory gap, the main argument for ontological physicalism, the argument from causation, looses its force. For if one takes physicaVnonphysical causation and ontological physicalism to be equally mysterious, as physicalists who accept the explanatory gap are inclined to do, there is little justification for accepting ontological physicalism rather than rejecting the causal closure of the physical.     

Defending the piggyback principle against Shapiro and Sober’s empirical approach

Jaegwon Kim’s supervenience/exclusion argument attempts to show that non-reductive physicalism is incompatible with mental causation. This influential argument can be seen as relying on the following principle, which I call “the piggyback principle”: If, with respect to an effect, E, an instance of a supervenient property, A, has no causal powers over and above, or in addition to, those had by its supervenience base, B, then the instance of A does not cause E (unless A is identical with B). In their “Epiphenomenalism: The Dos and the Don’ts,” Larry Shapiro and Elliott Sober employ a novel empirical approach to challenge the piggyback principle. Their empirical approach pulls from the experiments of August Weismann regarding the inheritance of acquired characteristics. Through an examination of Weismann’s experiments, Shapiro and Sober extract lessons in reasoning about the epiphenomenalism of a property. And according to these empirically drawn lessons, the piggyback principle is a don’t. My primary aim in this paper is to defend the piggyback principle against Shapiro and Sober’s empirical approach.