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Paradox in Thought and Natural Language by Ethan Paradox in Thought and Natural Language By Ethan J Jerzak A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Philosophy in the Graduate Division of the University of California, Berkeley Committee in Charge Professor John MacFarlane, Co-chair Professor Seth Yalcin, Co-chair Professor John Steel Summer 2019 Paradox in Thought and Natural Language This dissertation is entirely the original work of the author. Copyright Ethan J Jerzak 2019 Abstract Paradox in Thought and Natural Language by Ethan J Jerzak Doctor of Philosophy in Philosophy University of California, Berkeley Professor John MacFarlane, co-chair Professor Seth Yalcin, co-chair Professor John Steel Around 600BC, Epimenides, a Cretan apparently discontented with the honesty of his compatriots, lamented that all Cretans are liars. Together with a few innocent assumptions, well-entrenched principles of logic entail that Epimenides’ lamentation cannot be true, and yet cannot be untrue—a flat contradiction. What’s gone wrong? In this dissertation, I argue that the source of the problem has been misdiagnosed as one about language (especially formal languages). The problem runs deeper, and stems from the structure of thought itself. The dissertation proceeds in two main stages. The first stage (Chapter 2) makes the case that that the intuitions that underlie the paradoxes come from natural languages, not from formal/mathematical ones. The Liar and related paradoxes are generally presented as constraints on the latter. Their lesson, the story goes, is that no formal theory strong enough to represent the primitive recursive functions can include a satisfactory truth predicate. I argue that it’s our natural-language competence with the truth predicate that underlies our understanding of what ‘satisfactory’ means here, which shifts the focus of the project to natural language semantics. In this domain, it’s tempting to think (and many have thought) that the problem with Epimenides’ utterance is that it fails to express a proposition, and this failure explains 1 why we have trouble assigning it a truth-value. Or, perhaps it does express a proposition, but not the one that it seems to express. Or, perhaps it can express a proposition, but which proposition it expresses depends on context. I argue that all such responses fail, in part because they cannot make sense of related attitude attributions. I can believe or disbelieve Epimenides, which wouldn’t be possible if his utterance didn’t express the proposition it seems to express. In the second stage, I argue that such paradoxes arise, not from the language/thought interface, but rather from thought itself. The first step in this argument concerns knowledge attributions (Chapter 3), where I develop and defend a novel solution to the Knower paradox. Then I move from attitude attributions to attitudes themselves (Chapter 4). Just as sentential truth and knowledge predicates gives rise to paradoxical sentences, seem- ingly innocent combinations of beliefs and desires give rise to paradoxical propositions—even when those beliefs and desires are not expressed in lan- guage. The possibility of such pathological combinations isn’t accounted for by any extant theory of mental content, and, I argue, provides support for a non-classical theory. Finally (Chapter 5) I consider an objection to these putative combinations of desires. I introduce what I call advisory desire reports, which seem to exhibit the radically externalist behavior that the previous chapter rejects. I conclude by oering reasons to think that the availability of these readings does not undermine the case for non-classical accounts of attitudes. 2 Acknowledgments There are many humans and institutions without which this dissertation could never have come to be. To my parents and siblings gratitude is due for myriad reasons, but especially for their politely declining to inquire too scrupulously into what graduate school in philosophy entails and portends. The greatest portion of intellectual debt I owe to the graduate community at Berkeley. Most of what I know about anything, I learned from arguments in 301 and at Wollheims. Particular (though by no means exhaustive) thanks to Adam Bradley, Melissa Fusco, Jim Hutchinson, Alex Kerr, Arc Koceruk, Richard Lawrence, Sven Neth, Emily Perry, Kirsten Pickering, Rachel Rudolph, Pia Schneider, and Umrao Sethi for particularly instructive yelling in this regard. Many people gave invaluable comments on drafts and presentations of embryonic forms of what follows. Thanks to Chloé de Canson, Wes Holliday, Hannes Leitgeb, John MacFarlane, and Seth Yalcin for comments on drafts of Chapter 3. Thanks also to audiences at Berkeley, ESSLLI, and the MCMP for entertaining presentations about it. For Chapter 4, thanks to Wes Holliday, Arc Kocurek, John MacFarlane, Sven Neth, Rachel Rudoph, and Seth Yalcin for helpful discussions and comments, and to audiences in Berkeley, San Diego, London, Barcelona, and Oxford. And for Chapter 5, thanks to Chloé de Canson, Janice Dowell, Arc Kocurek, Hannes Leitgeb, John MacFarlane, Francois Reçanati, Rachel Rudolph, and Seth Yalcin for helpful draft commenting, to an anonymous reviewer at The Journal of Philosophy for helpful comments and challenges, and to audiences at UC–Berkeley, UCL, the University of Konstanz, the Institute Jean-Nicod, and the MCMP. I’m very grateful to the DAAD, whose research grant allowed me to spend the 2015/16 academic year at the MCMP in Munich, and because of i whose two language grants I now speak passable German. Thanks to Hannes Leitgeb and the MCMP for agreeing to host me during this year; my time there was invaluable in fixing Chapter 3, and in writing the bulk of Chapter 5. And warm thanks to Catrin Campbell-Moore, Johannes Korbmacher, Hans- Christoph Kotzsch, Lavinia Picollo, Thomas Schindler, and Pia Schneider, who welcomed me into the MCMP community. I’d also like to thank the Mellon Foundation and American Council of Learned Societies, from whom I received a dissertation completion fellowship for the 2017/18 academic year. During this time I published some of the more finished parts, and wrote Chapter 4. Tons of advisers and mentors, both formal and informal, have helped me over the years to think and do philosophy better. Agnes Callard, Robert Pippin, and Jim Conant were all influential in kindling the desire to do philosophy. Without Tom Lockhart I might never have had the wherewithall to apply in the first place. At Berkeley, Hannah Ginsborg and Barry Stroud were formidable first year seminar leaders, and collectively taught me the value of slowing down. Wes Holliday provided insight and guidance in the writing of Chapter 3. Seth Yalcin, despite sternly warning me in my first year not to write a dissertation on the present topic, was otherwise a model of encouragement. And John MacFarlane was extremely helpful, both through his meticulous comments on drafts, and in being most active in reminding me that I would eventually have to turn in a dissertation. Two entities deserve special mention. First, the taco truck parked outside the Hotsy Totsy in Albany was a (sometimes alarmingly exclusive) source of nourishment during the final writing stages. And Schmidt’s Pub in Albany served as the location where the greatest number of words contained herein were actually penned. To these two establishments jointly is this dissertation dedicated. ii Contents Acknowledgments i Contents iii 1 Introduction 1 1.1 Chapter 2: Liars, Propositions, and Contexts . 3 1.2 Chapter 3: Non-Classical Knowledge . 4 1.3 Chapter 4: Paradoxical Desires . 5 1.4 Chapter 5: Two Ways to Want . 5 1.5 Conclusion . 6 2 Liars, Propositions, and Contexts 7 2.1 A brief introduction to the Liar . 9 2.2 Intuitive responses . 13 2.3 Banning self-reference . 14 2.4 Failure to express a proposition . 15 2.5 Two kinds of context-based approaches . 19 2.6 Indexical truth predicate (Burge) . 19 2.7 Indexical domain of quantification over propositions (Glanzberg) . 20 2.8 Whither T-out and T-in? . 23 2.9 Two problems for this approach . 29 2.10 Upshot . 33 3 Non-Classical Knowledge 34 3.1 The Knower paradox . 34 3.2 A solution, outlined . 41 3.3 Mathematical knowledge . 52 iii Contents 3.4 The solution, evaluated: natural language . 59 3.5 Concluding thoughts: robustness, new paradoxes . 63 Appendix A . 65 Appendix B . 72 4 Paradoxical Desires 75 4.1 The paradox . 75 4.2 Responses . 77 4.3 Denying the case . 78 4.4 Intrinsic case-denying . 79 4.5 Relational case-denying . 82 4.6 Denying a principle of desire-satisfaction . 84 4.7 Non-classical thought . 87 5 Two Ways to Want? 93 5.1 Existing proposals . 97 5.2 ‘Wants’ in the consequent of conditionals . 102 5.3 Overreaction: perfect information . 106 5.4 Information-neutral desires . 110 5.5 ‘Wants’ and ‘Ought’ . 115 5.6 Whither the predictive ‘wants’? . 117 5.7 The purpose of desire attributions . 121 Appendix C . 122 6 Conclusion 130 Bibliography 135 iv Chapter 1 Introduction The Liar paradox is one of the oldest problems in philosophy. Sometime around 600BC, Epimenides, a Cretian apparently discontented with the honesty of his compatriots, lamented that all Cretians are liars. Together with a few assumptions—that liars are those who only say false things, that as a matter of fact all other Cretians are liars, and that everything Epimenides had said until then was a lie—well-entrenched principles of logic entail that Epimenides’ statement cannot be true, and yet cannot be untrue, a flat contradiction. And these assumptions are not necessary in contemporary versions of the paradox. Suppose Epimenides had simply said: (1) The sentence I’m uttering right now isn’t true. (Liar sentence) Then (1) can’t be true—if it were true, then it wouldn’t be true, since it says that it isn’t true.
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