PHYSICALISM AND EPIPHENOMENAL PROPERTIES

PHYSICALISM AND THE CHALLENGE

OF EPIPHENOMENAL PROPERTIES

By

NEIL CAMPBELL, M.A.

A Thesis

Submitted to the School of Graduate Studies

in Partial Fulfillment of the Requirements

for the Degree

Doctor of Philosophy

McMaster University

Copyright by Neil Campbell, August 1997

DOCTOR OF PHILOSOPHY ( 1997) McMaster University

(Philosophy) Hamilton, Ontario

TITLE: Physicalism and the Challenge of Epiphenomenal Properties.

AUTHOR: Neil Campbell, M.A. (McMaster University)

SUPERVISOR: Professor Evan Simpson

NUMBER OF PAGES: v, 149

ABSTRACT

The following dissertation is an examination of arguments against physicalism.

Physicalism is a thesis in the philosophy of mind that is constituted by two central claims:

(1) the ontological claim that everything that exists is ontologically physical and that human

beings are among such things; (2) the explanatory claim that all facts about human beings

and all explanations of their behaviour are dependent on and determined by physical facts

and explanations. It has frequently been asserted that there are properties that escape

capture in physicalist accounts of human behaviour, thereby undermining (2). Such

properties are usually thought to be lacking causal powers, and hence have been called

"epiphenomenal." The epiphenomenalist objections have long been thought to represent a

serious obstacle to physicalism. My aim is to show that the objections that are motivated by

epiphenomena} properties are unconvincing.

My discussion proceeds in two stages. In the first stage I examine the

epiphenomenalist objections in detail and show that in their most persuasive forms they

demonstrate that physicalism has certain explanatory inadequacies. The critics of

physicalism believe that these shortcomings lead to the denial of the explanatory

completeness of physicalism, and I try to make their case as charitably as I can. In the

second stage of the argument I invoke the relation of psycho-physical supervenience and

show that the desired conclusion does not follow, even if we admit that physicalism has

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certain explanatory failings. The overall conclusion of this dissertation is that the

epiphenomenalist objections to physicalism are completely undermined and hence that

properties which were thought to be epiphenomena! do not represent a serious obstacle to

physicalisrn as was previously thought. My intention is that this discussion push forward

work in the philosophy of mind and point the way to a more adequate articulation of

physicalisrn.

ill

Acknowledgements

I would like to express my gratitude to those who have served on my thesis committee for

their insightful comments, guidance, and support. This is especially true in the case of

Evan Simpson, who has taken a great deal of care and thought in his criticisms of earlier

drafts of this thesis, and for which I am extremely grateful. My work is much more precise

and has taken more interesting directions as a result of Evan's suggestions. I would also

like to thank Evan for the opportunity to serve as his research assistant in 1996. My work

with Evan on the course in the philosophy of mind provided the occasion to develop some

common philosophical ground between us and was very helpful to my research.

I would also like to express my thanks to a very special circle of friends who have

made my research at McMaster one of the most enjoyable experiences of my life.You all

know who you are. Thanks also to my parents Janis Hoogstraten and Colin Campbell, and

my adopted "Aunties" Jane and Sandy for their encouragement and all of those Thai

dinners when the writing got to be too much. Special thanks to Stan Clarke, a dear friend

and mentor. And thanks also to Melissa Otto, who happily entered my life toward the end

of my research and played a significant role in sustaining my sanity throughout the stresses

associated with the final stages of my Ph.D. Finally, I wish to thank the Social Sciences

and Humanities Research Council for their financial support which made a tremendous

difference to my ability to finish my research on time.

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Table of Contents

Chapter 1: Introduction .......................................................................... 1-16

Chapter 2: Anomalous Monism and Epiphenomenalism ................................... 17-57

1. The Standard Objection to Anomalous Monism ................................21-36

2. Reformulating the Epiphenomenalist Objection ................................ .36-57

Chapter 3: The Problem of Qualia ........................................................... .58-94

1. Inverted Qualia ......................................................................62-77

2. Jackson's Knowledge Argument ................................................78-94

Chapter 4: Supervenience ....................................................................95-132

1. Supervenience and Dependence ................................................99-118

2. Supervenience and Explanatory Completeness ............................... 118-132

Chapter 5: Conclusions and Further Problems ........................................... 133-139

Bibliography ................................................................................. 142-149

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Chapter 1

Introduction

The "mind-body problem" as such is no longer of great concern to contemporary

philosophers. I suspect this is due to the growing consensus that some form of physicalism

is true, and thus that questions about ontology are no longer of great interest.I However,

this does not mean that philosophers have stopped worrying about the mind. On the

contrary, the number of recent books and articles by philosophers on consciousness

indicates that the "philosophy of mind" remains at the forefront ofAnglo-American analytic

philosophy. Since most philosophers are convinced of the truth of physicalism much work

in the philosophy of mind is concerned with working out the details of how conscious

mental phenomena are physically realized. Generally speaking, among physicalists there

are two attitudes toward this endeavor. On one side there are theories that claim conscious

mental states can be incorporated into a broadly physical explanatory framework, while on

the other side there are theories that deny this is possible. The first group is constituted by

theories that show that mental states are identical with physical states of the brain or body

(Type-Identity,2 Token-ldentity,3 and with some qualifications, Functionalism4). The

I For an example of this attitude see William Seager, Metaphysics of Consciousness, Chapter 1. (New York: Routledge, 1991).

2 U. T. Place, "Is Consciousness a Brain Process?" British Journal of Psychology 47 ( 1956) pp. 44-50; J. J. C. Smart, "Sensations and Brain Processes," Philosophical Review 68 (1959) pp. 141-156.

3 Donald Davidson, (1970b) "Mental Events," in Davidson Essays on Actions and Events (Oxford: Oxford University Press, 1980).

4 David Lewis, (1978) "Mad Pain and Martian Pain," in Readings in Philosophy of Psychology Vol. l, ed. Ned Block (Cambridge: Harvard University Press, 1980).

1

2

second group, which denies there can be a physical understanding of the mind, divides into

two categories. First, there are the proponents of Eliminative Materialism.5 They claim

there is nothing to understand about the relationship between mental phenomena and the

physical sciences because there are no such things as mental phenomena. Beliefs, desires

and other mental states are theoretical entities belonging to a theory of behaviour known as

"folk psychology." Since, in their view, folk psychology is a false and misleading theory

of human behaviour its theoretical posits will be eliminated along with the theory when it is

eventually replaced by a more accurate scientific account of behaviour. Therefore, rather

than worry about how to render "facts" about our "mental" lives consistent with our

physical understanding of the rest of Nature, we should instead appreciate that there are no

such facts to begin with. At the other end of the spectrum is the "New Mysterianism"

which claims that due to contingent facts about our cognitive capacities it is conceptually

impossible for us to understand how mental states are physically realized, even though they

are physical phenomena.6

The philosophical terrain of physicalism is thus variegated indeed, but despite the

fact that these theories all have different approaches to the mind and therefore have different

conceptions of how it is physically realized, they all agree with the basic premise that

physicalism is true. The view that human beings are composed of completely physical

substance and that their behaviour is explainable in terms of physical concepts has gained

wide acceptance and (as the range of different forms of physicalism attests) has become

much more complex than the early materialism of Descartes' critics. This is in no small part

5 Paul Churchland, Matter and Consciousness (Cambridge: MIT Press, 1984); William Ramsey, Stephen Stich, and Joseph Garon, "Connec