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Scientific Progress at the Boundaries of Experience

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Scientific Progress at the Boundaries of Experience SCIENTIFIC PROGRESS AT THE BOUNDARIES OF EXPERIENCE by Nora Mills Boyd B.Sc. in Physics and Philosophy, University of British Columbia, 2008 M.A. in Philosophy, University of Waterloo, 2010 Submitted to the Graduate Faculty of the Kenneth P. Dietrich School of Arts & Sciences in partial fulfillment of the requirements for the degree of Doctor of Philosophy University of Pittsburgh 2018 UNIVERSITY OF PITTSBURGH DIETRICH SCHOOL OF ARTS AND SCIENCES This dissertation was presented by Nora Mills Boyd It was defended on March 13th 2018 and approved by John D. Norton, History and Philosophy of Science Robert Batterman, Philosophy Christopher Smeenk, Philosophy at Western University James Woodward, History and Philosophy of Science Dissertation Director: John D. Norton, History and Philosophy of Science ii SCIENTIFIC PROGRESS AT THE BOUNDARIES OF EXPERIENCE Nora Mills Boyd, PhD University of Pittsburgh, 2018 My dissertation introduces a new empiricist philosophy of science built on a novel charac- terization of empirical evidence and an analysis of empirical adequacy appropriate to it. I analyze historical and contemporary cases primarily, though not exclusively, from the space sciences attending carefully to the intricate practices involved in data collection and pro- cessing. I argue that the epistemic utility of empirical results as constraints on theorizing depends on the conditions of their provenance and that therefore information about those conditions ought to be included in our conception of empirical evidence. I articulate the con- ditions requisite for adjudicating the empirical adequacy of a theory with respect to some evidence and argue that much more background information is required for this adjudication than has been widely appreciated. Although my account is strictly anti-realist, this project is a defense of a sense of epistemic progress in science. Empirical evidence, as I have de- fined it, genuinely accumulates over the history of human inquiry. We learn that whatever theoretical framework we propose for understanding what the world is like will have to be consistent with this growing evidential corpus. iii TABLE OF CONTENTS PREFACE ......................................... vii 1.0 INTRODUCTION: EPISTEMIC PROGRESS IN SCIENCE ......1 2.0 THE MINIMAL COMMITMENT OF EMPIRICISM ..........5 2.1 VARIETIES OF EMPIRICISM.........................5 2.2 EXPLICATING THE `TRIBUNAL OF EXPERIENCE'...........7 2.3 RE-CASTING FULL-BORE EMPIRICISM.................. 12 2.4 WHAT IS DISTINCTIVELY `EMPIRICAL'?................. 13 2.4.1 Data are empirical relative to a target and a context.......... 14 2.4.2 Troublesome cases............................. 22 3.0 EVIDENCE ENRICHED ............................ 26 3.1 INTRODUCTION................................ 26 3.2 ENRICHED EVIDENCE............................ 29 3.3 BENEFITS OF ENRICHED EVIDENCE................... 37 3.4 CONCLUDING REMARKS........................... 45 4.0 EMPIRICAL ADEQUACY ........................... 46 4.1 INTRODUCTION................................ 46 4.2 ADJUDICATING EMPIRICAL ADEQUACY................. 49 4.3 SALVAGING EVIDENCE............................ 52 4.3.1 Forward direction............................. 53 4.3.2 Reverse direction............................. 59 4.4 DATA STEWARDSHIP............................. 60 4.5 CONCLUDING REMARKS........................... 69 iv 5.0 THE VARIETIES OF EMPIRICAL CONSTRAINT ........... 70 5.1 INTRODUCTION................................ 70 5.1.1 An epistemic shift............................. 70 5.1.2 Resisting the shift............................. 74 5.2 PUTTING BOUNDS ON THE DARK ENERGY EQUATION OF STATE PARAMETER.................................. 77 5.2.1 Observables................................ 79 5.2.2 Hooking up the observables........................ 83 5.3 THE DISTINCTIVENESS OF THE STRATEGY............... 86 5.3.1 Against construing putting bounds on a parameter as traditional hy- pothesis testing.............................. 86 5.3.2 Exploratory experimentation....................... 87 5.3.3 Against construing putting bounds on a parameter as systematic pa- rameter variation............................. 89 5.4 CONCLUDING REMARKS........................... 95 6.0 CONCLUSIONS: EPISTEMIC ATTITUDES AND PROGRESS .... 98 APPENDIX. HULSE-TAYLOR PULSAR ..................... 108 BIBLIOGRAPHY .................................... 112 v LIST OF FIGURES 1 Data from the Arecibo radio telescope...................... 19 2 Babylonian table of lunar eclipses ©Trustees of the British Museum..... 54 3 Constraints on dark energy equation of state parameters, from Planck Collab- oration(2016a, 40)................................. 80 4 Intermediary parameters, from Albrecht, Amendola, Bernstein, Clowe, Eisen- stein, Guzzo, Hirata, Huterer, Kolb, and Nichol(Albrecht et al., 29)..... 81 5 SNe Ia light curves, from Perlmutter(2003, 54)................. 84 6 Current limits on the PPN parameters, Table 4 from Will(2014, 46)..... 92 7 Constraints on slow-roll parameters, Figure 10 from Planck Collaboration (2016b, 14)..................................... 93 8 Elements of an enriched line of evidence..................... 109 vi PREFACE I owe huge debt of gratitude to my advisor John Norton, who expertly shepherded me through the entire process of graduate school. John, thank you for being an incredible mentor and especially for always providing instantaneous constructive feedback that pushed me to do my best work and to find a bold philosophical stance that I really care about. I am grateful also to three Jims (Woodward, Bogen, and Weatherall) for their support and for encouraging me to think in directions that I am sure I will continue to grapple with for a long time to come. I could not possibly thank David Cola¸coand Aaron Novick with sufficient profusion for reading countless drafts over the past six years, for their criticisms and advice, and for being my intellectual brothers. I am also immensely grateful to fellow travelers Michael Miller, Siska De Baerdemaeker, Katie Creel, Dana Matthiessen and Liam Kofi Bright for their friendship, dialog, and for being there when I needed them most. I also want to acknowledge several people who have contributed to my education over the years without whom I would not be where I am today. Thank you to Matthew Capdevielle, a friend and mentor who taught me both physics and philosophy in high school and to Alan Richardson, my undergraduate philosophy of science professor who provided much needed encouragement and support in pursuing my higher education in philosophy. Much gratitude also to Derek Storm, Doug Will, and Greg Harper at the nuclear physics lab under whose guidance my love of experimental physics was cemented. Doug and Greg, you are family, thank you for being there fore me. Finally, I want to acknowledge my master's degree advisor Doreen Fraser who rocketed me into the Pittsburgh HPS scene. I have been extremely privileged to have the benefit of substantive support from my family. Both of my parents have been role models for me throughout my education. Watching my mother Beth Mills earn her PhD while I was in middle school was a very formative vii experience for me. I have always been inspired by her as a teacher and a scholar and I am so grateful for her help and confidence from the beginning. Among innumerable other things, I owe my dad Andrew Boyd immense gratitude for introducing me to what is wonderful, awesome, and puzzling about physics and the cosmos from an early age. Dad, you are my favorite model of the life-long learner. A thousand thanks both to my dad and to my stepmother Cristal Weber for sending me to university and for always supporting me in my education. Thank you also to my grandfather Robert Boyd, for fueling my love of science with stories. Finally, I want to extend my deep gratitude to Zander Winther. Zander, thank you for introducing me to some of the best philosophy, for moving with me multiple times for school and for adventure, and for your wisdom. viii 1.0 INTRODUCTION: EPISTEMIC PROGRESS IN SCIENCE Philosophers of science who engage with the problem of scientific progress have (at least since Kuhn) looked to the history of science for their philosophical ore. This historically-oriented philosophy of science has often focused on apparent discontinuities in the scientific record marked by revolutions in scientific theory. Philosophy of scientific progress has been primarily concerned with giving accounts of the familiar trajectory beginning with Ptolemy, passing through Copernicus, Kepler, Galileo, Newton and ending with Einstein, with the trajectory from alchemy through the chemical revolution, and so on...in short: understanding how mature scientific fields emerged from a graveyard of diverse worldviews. As a consequence, some philosophers have adopted non-epistemic accounts of scientific progress (what Bird(2007) calls \functional-internalist" accounts). For instance, those who understand the history of science as a series of paradigms and revolutions have a difficult time reconciling their view with the plausibility of cumulative epistemic progress. Notoriously, Kuhn(1975) resorted to a kind of pragmatic understanding of scientific progress as progress in problem-solving capabilities rather than increased knowledge about the natural world. According to Kuhn, scientists adopt a new paradigm when the growing pile of unsolved anomalies besetting their old paradigm becomes unbearable; \[t]he scientific community is a supremely efficient instrument for maximizing the number
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