Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2004 A Partial Defense of Compatibilism Jason Turner Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] THE FLORIDA STATE UNIVERSITY COLLEGE OF ARTS AND SCIENCES A PARTIAL DEFENSE OF COMPATIBILISM By Jason Turner A Thesis submitted to the Department of Philosophy in partial fulfillment of the requirements for the degree of Master of Arts Degree Awarded: Summer Semester, 2004 The members of the Committee approve the Thesis of Jason Turner defended on 25 June 2004. _______________________ Alfred R. Mele Professor Directing Thesis _______________________ Eddy Nahmias Committee Member _______________________ Thomas M. Crisp Committee Member The Office of Graduate Studies has verified and approved the above named committee members. ii ACKNOWLEDGEMENTS I would like to thank Zac Ernst, Peter Hanowell, Matt James, Jeremy Kirby, Kirk Ludwig, Thomas Nadelhoffer, and Christopher Pynes for helpful suggestions, comments, and criticisms regarding the papers and ideas that led up to this thesis. I am especially grateful to Tom Crisp, Al Mele, and Eddy Nahmias for their extensive and helpful comments both on this thesis itself and on its ancestral papers. I would also like to thank Joseph Keim Campbell for first introducing me to the metaphysics of free will, my wife Starr for putting up with me during the writing process, and my father Ted for his sound advice that this thesis aims to follow. iii TABLE OF CONTENTS List of Figures ......................................................................................................... v Abstract ............................................................................................................... vi 1. INTRODUCTION ................................................................................................... 1 2. HOW NOT TO BE AN ELIMINATIVIST ABOUT FREE WILL......................... 7 2.1. Eliminativism and the Argument For It....................................................... 7 2.1.1. Types of Eliminativism 2.1.2. Intuitional Anarchy 2.1.3. “Free Choice” and Natural Kind Terms 2.1.4. The Argument 2.2. Meaning as Use Plus Eligibility................................................................... 19 2.2.1. Putnam’s Model-Theoretic Paradox 2.2.2. Use Plus Eligibility and the Bottom-Up Argument 2.2.3. An Eliminativist Objection 2.3. Indeterminate Meaning and Contextualism................................................. 27 2.4. Further Implications..................................................................................... 33 3. THE INCOMPATIBILITY OF FREE WILL AND NATURALISM..................... 40 3.1. The Consequence Argument........................................................................ 40 3.2. Naturalism and the Supervenience Argument ............................................. 43 3.2.1. Choosy Actions 3.2.2. Causal Relations 3.2.3. The Supervenience Argument: A First Pass 3.2.4. The Argument for Trickier Cases 3.3. Implications ................................................................................................. 54 3.4. Objections and Replies ................................................................................ 58 4. PUTTING IT ALL TOGETHER: IN DEFENSE OF COMPATIBILISM ............. 70 4.1. Limitations of an Offensive Defense ........................................................... 70 4.2. Introducing the Use-Plus-Eligibility Argument for Compatibilism ............ 73 4.3. Agent-causation, (β□), and the Use-Plus-Eligibility Argument .................. 75 4.4. Conclusion ................................................................................................... 82 iv REFERENCES ......................................................................................................... 86 BIOGRAPHICAL SKETCH ....................................................................................... 92 v LIST OF FIGURES Figure 1: The causal structure of r’s supervenience base ............................................ 49 Figure 2: “In-the-middle” indeterminism .................................................................... 49 Figure 3: “At-the-end” indeterminism ......................................................................... 52 vi ABSTRACT Compatibilism is the view that free will can exist even if determinism — the thesis that there is only one physically possible future at any given time — is true. In this thesis, I defend compatibilism by arguing against two of its main rivals. I first argue against necessary eliminativism — the view that free will is impossible — by deploying an attractive view of language (Lewis, 1983, 1984; Sider, 2001) to show that, so long as ordinary folk are liable to experience conflicting intuitions about how to use the term ‘free,’ it will refer to some property which is possibly exemplified. I then argue that libertarians — believers in free will who hold that it is incompatible with determinism — must reject either a naturalistic view of the world with no ontological commitments above and beyond those proscribed by science or the soundness of the best argument in favor of libertarianism (van Inwagen, 1983, ch. 3). Finally, I sketch a way a proponent of compatibilism can use my arguments against necessary eliminativists and naturalistic libertarians to offer a positive argument for compatibilism. vii CHAPTER 1 INTRODUCTION According to my father, the best defense is a good offense. This thesis aims to follow the implicit advice in that adage, defending compatibilism — the view that agents may have free will even if determinism is true — by going on the offensive and attacking some of compatibilism’s main opponents. By determinism, I mean the thesis that there is only one physically possible future given the state of the universe at any given moment. We can, following the lead of Peter van Inwagen (1983, pp. 58-65), make this a little more precise. Say that a proposition φ “expresses a state of affairs at a time, t,” if and only if φ asserts that some state of affairs obtains at t. If φ expresses a state of affairs at t, then call φ “immediate” if and only if φ does not entail any proposition ψ that expresses a state of affairs at t* (where t* ≠ t) and call φ “complete” if and only if, if φ is true, then for every true immediate ψ which expresses a state of affairs at t, φ entails ψ. Determinism is then the thesis that, if L is a proposition that expresses the laws of nature, then any true, immediate, and complete proposition φ that expresses a state of affairs at some time, conjoined with L, entails any true proposition ψ whatsoever — i.e., that □((φ & L) → ψ).1 By free will I mean the kind of freedom that is required in order for agents to count as morally responsible. There are a number of uses of the word “free” in English, and not all of them are related to philosophical issues involving free will. Political and economic freedom, for instance, are desirable things, but they are not the grand prizes philosophers are angling for when they go looking for free will. Rather, “free will” becomes, roughly, a tag for “the kind of freedom that grounds moral responsibility” — i.e., a kind of freedom necessary for moral responsibility not entailed by any other kind of freedom necessary for moral responsibility. 1 There may be other reasons that freedom of this kind is thought desirable. For instance, it is sometimes thought that the very same property that is a necessary condition for being morally responsible is also a necessary condition for being an appropriate “target” of reactive attitudes — attitudes like resentment, gratitude, and love (P. Strawson, 1962) — or for being truly creative, autonomous, unique, and having a certain sort of dignity (Kane, 1996, pp. 81-89). So although we may use moral responsibility to fix the sort of property that free will is supposed to be, there may be a number of other quite valuable things that free will is supposed to gain for us. Compatibilism thus becomes the view that free will, in this sense, is possible even if determinism, as defined above, turns out to be true. Incompatibilism, or the view that determinism precludes free will, is the denial of compatibilism. Incompatibilists divide further into two camps: those who believe that people have free will, and those who do not. Incompatibilist believers in free will are called libertarians. Event-causal libertarians (Ekstrom, 2000; Kane, 1989, 1996, 1999) hold that suitably located indeterministic processes of the sort posited by quantum physics are all that is needed to escape the threat to free will that determinism provides. Agent-causalists (Chisholm, 1964; Clarke, 2003; O’Connor, 2000; Taylor, 1963), however, contend that suitably located indeterminism is not enough. The indeterministic processes postulated by quantum physics are all instances of ordinary (albeit indeterministic) event causation — instances of one event causing another. Agent-causalists insist that free will requires a different sort of causation entirely — agent-causation, in which a substance (an agent), rather than an event, is the cause of an action. It is generally held that ordinary (non- agent-causal) claims that appear to ascribe causal efficacy to an agent (like “John caused the roof to fall”) can be analyzed into causal claims that only involve events (like “John’s pushing on that wall caused the roof to fall”). Agent-causalists hold that genuine