Georgia State University ScholarWorks @ Georgia State University Philosophy Theses Department of Philosophy 8-7-2018 A Critique of Compatibilist-Libertarianism Zachary Peck Follow this and additional works at: https://scholarworks.gsu.edu/philosophy_theses Recommended Citation Peck, Zachary, "A Critique of Compatibilist-Libertarianism." Thesis, Georgia State University, 2018. https://scholarworks.gsu.edu/philosophy_theses/238 This Thesis is brought to you for free and open access by the Department of Philosophy at ScholarWorks @ Georgia State University. It has been accepted for inclusion in Philosophy Theses by an authorized administrator of ScholarWorks @ Georgia State University. For more information, please contact [email protected]. A CRITIQUE OF COMPATIBILIST-LIBERTARIANISM by ZACHARY PECK Under the Direction of Eddy Nahmias, PhD ABSTRACT Christian List has recently defended what he refers to as a compatibilist-libertarian theory of free will. He attempts to satisfy the libertarian requirement for alternative possibilities without assuming the falsity of physical determinism. To do so, List relies on a multi-level modal theory that he developed with Marcus Pivato. In this theory, List and Pivato demonstrate the compatibility of physical determinism and agential indeterminism. The success of compatibilist- libertarianism essentially hinges upon whether or not List and Pivato’s theory is truly consistent with a non-hypothetical conception of possibility. In this paper, I argue that, despite his attempt to distance himself from a standard compatibilist (i.e. hypothetical) conception of possibility, List remains committed to such a hypothetical conception. I also argue that List’s theory of agential causation is implausible given his modal interpretation of agency. Therefore, I conclude that compatibilist-libertarianism is an implausible theory of free will. INDEX WORDS: Modal logic, Free will, Compatibilism, Libertarianism, Levels, Determinism A CRITIQUE OF COMPATIBILIST-LIBERTARIANISM by ZACHARY PECK A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Arts in the College of Arts and Sciences Georgia State University 2018 Copyright by Zachary Peck 2018 A CRITIQUE OF COMPATIBILIST-LIBERTARIANISM by ZACHARY PECK Committee Chair: Eddy Nahmias Committee: Neil Van Leeuwen Ed Cox Electronic Version Approved: Office of Graduate Studies College of Arts and Sciences Georgia State University July 2018 v ACKNOWLEDGEMENTS First and foremost, I would like to thank Eddy Nahmias. If I were to indicate all of the ways in which Eddy has influenced the following work, then the vast majority of the footnotes would be solely dedicated to acknowledging his contribution. I am quite confident that no one has ever spent as much time reading my written work as he has. For this, I am incredibly grateful. In particular, I must thank Eddy for helping me improve the clarity of my writing – not only in this work, but in general. If anything that follows is particularly clear, it is most likely because of a suggestion that he has made. I would also like to thank Neil van Leeuwen and Ed Cox for providing me with many helpful comments on earlier versions of this work. In particular, I am thankful for the many hours that they have spent trying to understand my convoluted argumentation – if it weren’t for their comments and criticisms, the argumentative structure of this paper would be quite poor. Additionally, I would like to thank Dan Weiskopf for helping me better understand the philosophical literature on levels. Although I am quite sure that my discussion of levels remains overly abstract and detached from the practice of actual scientists, I can at least attest to being aware of this shortcoming thanks to Dan. In the future, I hope to develop a more nuanced understanding of the concept of levels in science. Finally, I would like to thank two of my classmates for spending many hours listening to me ramble about the relationship between modal logic and free will. Both Tiffany Zhu and Bobby McKinley have helped me clarify many of the ideas in this paper more clearly. In particular, if it weren’t for the many discussions I have had with Bobby, then there would almost certainly be more logical errors in this work than there currently are. vi TABLE OF CONTENT ACKNOWLEDGEMENTS ............................................................................................. v LIST OF FIGURES ....................................................................................................... viii 1 INTRODUCTION ...................................................................................................... 1 2 COMPATIBILIST-LIBERTARIANISM ................................................................ 6 2.1 Modality in a leveled world ................................................................................ 6 2.2 Supervenience, multiple realization, and emergent indeterminism ............... 9 2.3 A non-hypothetical conception of possibility .................................................. 14 3 THE INVALIDITY OF CROSS-LEVEL MODAL REASONING ..................... 19 3.1 The consequence argument .............................................................................. 19 3.2 The compatibilist-libertarian response to the consequence argument ......... 22 4 META-LEVELS ....................................................................................................... 25 4.1 Meta-level modality ........................................................................................... 26 4.2 A meta-level version of the consequence argument ....................................... 34 5 A DILEMMA FOR THE COMPATIBILIST-LIBERTARIAN .......................... 38 5.1 The causal source objection .............................................................................. 38 5.2 The randomness objection ................................................................................ 40 6 CONCLUSION ......................................................................................................... 45 REFERENCES ................................................................................................................ 46 APPENDICES ................................................................................................................. 48 vii Appendix A. Lower-level determinism entails meta-level determinism ................ 48 viii LIST OF FIGURES Figure 1. Emergent Indeterminism .............................................................................................. 12 Figure 2. Levels ............................................................................................................................ 43 Figure 3. Multiple Realization ...................................................................................................... 43 1 1 INTRODUCTION Christian List (2014) has recently defended what he refers to as a “compatibilist- libertarian” theory of free will. His theory is compatibilist insofar as it demonstrates that free will is compatible with physical determinism, while it is libertarian insofar as it requires agential indeterminism. He suggests that it may be described as both “cross-level compatibilist” and “agential-level libertarian” (unpublished-1, 18). In other words, he thinks that free will is compatible with the truth of determinism at the physical level, while it is not compatible with determinism at the level at which free agency must be described, i.e., the agential level. Notice that this theory assumes that agential indeterminism is compatible with physical determinism. Such cross-level compatibility assumes that the truth of determinism is relative to a specific level, such that determinism may be true at one level while false at another.1 The conceptual support for such a level-specific conception of determinism is what I will refer to as the multi-level modal theory, as developed by List and Pivato (2014). According to their theory, agential indeterminism is compatible with physical determinism if we assume (as they do) that “higher-level states [such as agential states] are typically multiply realizable by lower-level states” (2014, 20). In their jargon, the basic idea is that a multiply-realized, higher- level history may have multiple possible (higher-level) futures, despite the fact that each of the history’s multiple lower-level realizers only has a single possible (lower-level) future. So, because there are multiple lower-level histories that can realize a single higher-level history, there may be multiple possible higher-level futures, even though each lower-level history only has a single possible future. Therefore, List and Pivato conclude that higher-level indeterminism 1 Traditionally, determinism is considered to be a property of entire worlds, such that either determinism is true of the entire world, or it is not. The idea that determinism and indeterminism can both be true at different levels of the same world is a view that is, as far as I know, unique to List. 2 (more than one possible future) is compatible with lower-level determinism (only one possible future) if the higher level is multiply realizable at the lower level. The key assumption is that all of the modal propositions that are relevant to free agency are level-specific. By demonstrating the compatibility of physical determinism and agential indeterminism, List attempts to develop a compatibilist theory of free will that satisfies the libertarian requirement for