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1 Knowledge and Knowers of the Past: a Study in the Philosophy Of Knowledge and knowers of the past: A study in the philosophy of evolutionary biology. Submitted by Thomas Bonnin to the University of Exeter as a thesis for the degree of Doctor of Philosophy in Philosophy In May 2018 This thesis is available for Library use on the understanding that it is copyright material and that no quotation from the thesis may be published without proper acknowledgement. I certify that all material in this thesis which is not my own work has been identified and that no material has previously been submitted and approved for the award of a degree by this or any other University. Signature: ………………………………………………………….. 1 ABSTRACT This dissertation proposes an exploration of a variety of themes in philosophy of science through the lens of a case study in evolutionary biology. It draws from a careful analysis and comparison of the hypotheses from Bill Martin and Tom Cavalier-Smith. These two scientists produced contrasted and competing accounts for one of the main events in the history of life, the origin of eukaryotic cells. This case study feeds four main philosophical themes around which this dissertation is articulated. (1) Theorizing: What kind of theory are hypotheses about unique events in the past? (2) Representation: How do hypotheses about the past represent their target? (3) Evidential claims: What kind of evidence is employed and how do they constrain these hypotheses? (4) Pluralism: What are the benefits and the risks associated with the coexistence of rival hypotheses? This work both seeks to rearticulate traditional debates in philosophy of science in the light of a lesser-known case of scientific practice and to enrich the catalogue of existing case studies in the philosophy of historical sciences. 2 Table of Contents Abstract ..................................................................................................................... 2 Acknowledgements .................................................................................................. 7 Chapter 1: Evolutionary biology between science and history. ........................... 9 Introduction ................................................................................................... 9 I. History away from Science? A rebuttal ................................................. 11 A. Historical sciences and human history .................................................. 11 B. Objection 1: “History is not a science” ................................................... 13 C. Objection 2: “Humans make a difference” ............................................ 17 II. Methodological possibilities .................................................................. 22 A. Metaphysical vs. practice-oriented philosophical projects ..................... 22 B. Naturalistic approaches in metaphysical and practice-oriented projects24 C. Integrated studies of scientific practice ................................................. 27 Conclusion .................................................................................................. 31 Chapter 2: Cavalier-Smith and Martin on the origin of eukaryotes .................... 34 Introduction ................................................................................................. 34 I. William Martin ...................................................................................... 35 A. In previous episodes ............................................................................. 35 B. The origin of eukaryotes ....................................................................... 36 II. Thomas Cavalier-Smith ....................................................................... 43 A. In previous episodes ............................................................................. 43 B. The neomuran revolution and the origin of eukaryotes ......................... 43 Concluding words ...................................................................................... 46 Chapter 3: Theories about unique events ............................................................ 47 Introduction ................................................................................................. 47 I. Narrative explanations and ephemeral mechanisms............................ 50 A. Narrative explanations .......................................................................... 50 B. Ephemeral mechanisms ....................................................................... 52 C. Convergences and tensions ................................................................. 55 D. Currie‟s simple and complex narratives ................................................ 60 II. Lineage explanations ............................................................................. 62 A. Introduction ........................................................................................... 62 3 B. Narrative explanations and ephemeral mechanisms as types of lineage explanations .............................................................................................. 66 III. Case study .............................................................................................. 71 A. Martin‟s hypothesis as a lineage explanation ........................................ 71 B. Cavalier-Smith‟s hypothesis .................................................................. 74 C. Analysis ................................................................................................ 76 Conclusion .................................................................................................. 77 Chapter 4: Hypotheses representing past events ............................................... 81 Introduction ................................................................................................. 81 I. Toon’s “make-believe” view ................................................................... 84 A. Props .................................................................................................... 84 B. Principles of generation ........................................................................ 85 C. Fictional truths ...................................................................................... 86 D. The benefits of exploration ................................................................... 86 II. Frigg and Nguyen’s DEKI account ........................................................ 87 A. Denotation ............................................................................................ 87 B. Exemplification ...................................................................................... 88 C. Keying-up ............................................................................................. 88 D. Imputation ............................................................................................. 89 E. Summary .............................................................................................. 89 III. Differences and reconciliation .............................................................. 89 B.. Lineage explanations as a case of D(E)K(I) ......................................... 92 Conclusion .................................................................................................. 95 Chapter 5: A survey into historical methodology ................................................ 98 Introduction ................................................................................................. 98 I. Quotes and insights ............................................................................ 99 II. Strengths and limits of the smoking gun view of the historical method ....................................................................................................... 104 A. Smoking guns - definition ................................................................. 104 B. Advantages ...................................................................................... 105 C. Limits ................................................................................................ 106 D. Summary .......................................................................................... 111 III. Omnivories, scaffolds and virtues ................................................... 113 A. Methodological omnivory and investigative scaffolds ....................... 113 4 B. Investigative scaffolds and productive speculation .......................... 119 C. Coherence and consilience .............................................................. 122 D. Summary .......................................................................................... 125 IV. The strength of evidence: Wylie on security ............................... 126 Conclusion ................................................................................................ 128 Chapter 6: A framework for evidential claims and the case of Archezoa........ 132 Introduction ............................................................................................... 132 I. Philosophical demands on evidential claims .................................. 133 II. Toulmin schemas .............................................................................. 135 A. Data, Claims and Warrants as the basis of Epistemic contexts ....... 136 B. Qualifiers .......................................................................................... 137 C. Backings and rebuttals ..................................................................... 138 D. Summary and philosophical
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