The Paradoxes of Time Travel
Wasserman (Ryan)
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Introductory Note

  1. This looked initially like rather a niche book, but it covers a very wide range of topics relevant to my Thesis on Personal Identity.
  2. I’ve added it to the ‘must read’ list.

Back Cover Blurb
  • Ryan Wasserman presents a wide-ranging exploration of puzzles raised by the possibility of time travel, including the grandfather paradox, the bootstrapping paradox, and the twin paradox of special relativity.
  • He draws out their implications for our understanding of time, tense, freedom, fatalism, causation, counterfactuals, laws of nature, persistence, change, and mereology.
  • The Paradoxes of Time Travel is written in an accessible style1, and filled with entertaining examples from physics, science fiction, and popular culture.
  • Ryan Wasserman is professor of philosophy at Western Washington University, and co-editor of "Chalmers (David), Manley (David) & Wasserman (Ryan) - Metametaphysics: New Essays on the Foundations of Ontology" (OUP 2009).

Amazon Review
  • Wasserman's book fills a gap in the academic literature on time travel. ... as far as I know, this is the first book-length work devoted to the topic of time travel by a metaphysician homed in on the most important metaphysical issues.
  • Wasserman addresses these issues while still managing to include pertinent scientific discussion and enjoyable time-travel snippets from science fiction.
  • The book is well organized and is suitable for good undergraduate metaphysics students, for philosophy graduate students, and for professional philosophers. It reads like a sophisticated and excellent textbook even though it includes many novel ideas.
    → John W. Carroll, Notre Dame Philosophical Reviews

Preface (Excerpted)
  • In the fall of 2005, I taught my very first introductory philosophy course. That course included a unit on freedom and determinism and I decided to conclude that section by spending a day on the grandfather paradox. That meeting ended up being so much fun that I added two extra days on the topic the next time I taught the class. Among other things, we discussed David Lewis’s definition of time travel, Robert Heinlein’s tales of causal loops, and Doc Brown’s explanation of branching timelines from the Back to the Future movies. Student feedback on these topics was so positive that I eventually- expanded the material into an entire course on time travel. The notes from that course went on to provide the basis of the book that you now hold.
  • This book retains many features of my' original classroom lectures. I have tried my best to introduce all of the topics in an entertaining way, and to provide as much background material as is required. I have also included many of the examples and illustrations that have proven helpful in class. My hope is that the resulting work is accessible to all students of philosophy, and that teachers will find the text useful in their own philosophy courses. I would like to thank all of the students who have discussed these topics with me over the years — your feedback has helped me to improve this work in many different ways. …
  • Another prominent feature of this book is its heavy use of examples from the science fiction genre. As will become clear, almost all of the philosophical issues raised by time travel have their roots in science fiction, and I have done my best to trace out the history of these ideas. I have been greatly aided in this task by Paul J. Nahin’s excellent book Time Machines: Time Travel in Physics, Metaphysics, and Science Fiction, and Michael Main’s comprehensive website The Internet Time Travel Database. Both of these works have provided me with endless examples and inspiration. I am also very grateful to the library staff at Western Washington University who helped me track down some truly obscure publications. My hope is that this research will help make this book of interest to science fiction fans, as well as philosophers.
  • Still, the main audience for this book will be professional philosophers — especially those with research interests in contemporary analytic metaphysics. Philosophers in this area will already be aware of some of the important issues raised by time travel – issues having to do with the nature of time, freedom, causation, and identity. However, philosophers in this area also know that, until this point, there has been no comprehensive study of these topics. That is the primary goal of this book — to survey, systematize, and expand upon the philosophical literature on time travel.
  • I would like to thank all of the philosophers who have helped me in this task by providing comments on earlier drafts of this work. This includes Thomas Hall, Daniel Howard-Snyder, Frances Howard-Snyder, Hud Hudson, David Manley, Ned Markosian, Gerald Marsch, Tim Maudlin, Jeff Russell, Michelle Saint, Neal Tognazzini, James Van Cleve, and two anonymous readers for Oxford University Press. I would also like to thank Andreas Riemann, who proofread the material on special relativity, and Jonathan Bennett and Stephanie Lewis, who provided me with unpublished materials relating to David Lewis’s work on time travel.
  • Finally, I gratefully acknowledge … permission to include portions of the following works2 in this book:-
    → "Hudson (Hud) & Wasserman (Ryan) - Van Inwagen on Time Travel and Changing the Past" (2010);
    → "Wasserman (Ryan) - Personal Identity, Indeterminacy And Obligation" (2013);
    → "Wasserman (Ryan) - Theories of Persistence" (2016); and
    → "Wasserman (Ryan) - Vagueness and the Laws of Metaphysics" (2017)

Contents
    Preface – ix
  1. Introduction – 1
    1. Time Travel – 2
    2. ...And Not – 8
    3. Possibility – 13
    4. Paradoxes – 18
  2. Temporal Paradoxes – 23
    1. Two Debates in the Philosophy of Time – 24
      1.1 – The ontology of time – 24
      1.2 – The reality of tense – 27
    2. Eternalisin and Time Travel – 30
    3. Presentism and Time Travel – 38
      3.1 – The no destination argument – 39
      3.2 – The definitional argument – 42
      3.3 – The annihilation argument – 46
    4. The Growing Block and Time Travel – 49
    5. Special Relativity and Time Travel – 55
    6. General Relativity and Time Travel – 65
  3. Paradoxes of Freedom I – 70
    1. Stories of Self-Defeat – 71
    2. Rewriting History – 74
    3. The Branches of Time – 78
      3.1 – The branching timeline model – 79
      3.2 – The inconsistency objection – 83
      3.3 – The immutability objection – 85
      3.4 – The irrelevance objection – 89
    4. Traveling in Hypertime – 90
      4.1 – The hypertime model – 90
      4.2 – Three advantages to the hypertime model – 94
      4.3 – Three objections to the hypertime model – 96
    5. The A-Model of Past-Alteration – 99
  4. Paradoxes of Freedom II – 107
    1. On – Lewis’s Way Out – 108
      1.1 – Clarifications – 108
      1.2 – Applications – 111
      1.3 – Reactions – 114
    2. Killing Baby Suzy – 114
      2.1 – Vihvelin on retrosuicide – 115
      2.2 – Vranas on retrosuicide – 120
      2.3 – Sider on retrosuicide – 124
    3. The Problem with Banana Peels – 130
      3.1 – Horwich on coincidences – 131
      3.2 – Smith on fallacious reasoning – 135
      3.3 – Smith on tomato rolls – 137
    4. Paradox without Freedom? – 139
  5. Causal Paradoxes – 145
    1. Preliminaries – 146
      1.1 – Causal loops – 146
      1.2 – Backward causation – 150
    2. The Bootstrapping Paradox – 154
    3. The Ex Nihilo Paradox – 157
    4. The Restoration Paradox – 163
    5. The Frequency Paradox – 165
    6. The Counterfactual Paradox – 171
      6.1 – Lewis’s theory – 172
      6.2 – Tooleys argument – 174
      6.3 – Tichy’s hat and Morgenbesser’s coin – 176
      6.4 – A unified solution – 179
  6. Paradoxes of Identity – 183
    1. Two Puzzles about Sameness and Difference – 184
    2. Perdurantism and Self-Visitation – 187
      2.1 – Perdurantism and persistence – 187
      2.2 – Perdurantism, change, and self-visitation – 189
      2.3 – The problem with temporal parts – 192
      2.4 – The problem with person parts – 194
    3. Endurantism and Self-Visitation – 197
      3.1 – Endurantism and persistence – 197
      3.2 – Endurantism, change, and self-visitation – 199
      3.3 – From relativism to compatibilism – 200
      3.4 – Endurantism and indiscemibility – 203
    4. Mereology and Multi-Visitation – 209
      4.1 – The identification account – 211
      4.2 – The composition account – 214
      4.3 – The constitution account – 216
      4.4 – The elimination account – 217
    5. The Strange Tale of Adam the Atom – 218
    References
    Index


In-Page Footnotes ("Wasserman (Ryan) - The Paradoxes of Time Travel")

Footnote 1: Footnote 2:
Book Comment

OUP (30 Nov. 2017). Hardback.


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