Brownian Motion and Molecular Reality

George E. Smith joined the Philosophy Department of Tufts University in 1977. He specializes in the critical assessment of evidence in the physical sciences especially during historical transitions in which areas of research go from struggling to extract high quality evidence out of data to becoming exceptionally effective in doing so. He served as Acting Director of the Dibner Institute for the History of Science and Technology at MIT from 2001 until 2006 and has twice been a Distinguished Visiting Professor in the Philosophy Department of Stanford University.Raghav Seth graduated from Tufts University in 2012 with a B.A. in Philosophy. After college, he worked as a research assistant at the McGovern Institute for Brain Research at MIT and then as an EMT in Essex County before transitioning to medical school at the Tufts University School of Medicine from which he graduated in 2018. He is currently an anesthesiology resident at Beth Israel Deaconess Medical Center.

• Preface Bibliographical Notice Chapter 1. Introduction 1.1 Brownian Motion and Molecular Reality: The "Lore" 1.2 Two Issues 1.3 Challenges to Our Second Issue 1.4 Why the Focus So Narrowly on Perrin? 1.5 Organization of the Monograph Chapter 2. The Historical Background: Molecular Theory as of 1900 2.1 On the "Hypothetical" Status of the Molecular Hypothesis 2.2 Kinetic Theory as a Means of Gaining Access to Molecules 2.3 The Problem Posed by the Specific Heats of Gases 2.4 Ostwald on How a Hypothesis Can Become Something More 2.5 A Further Dimension of the Dispute over Molecular-Kinetic Theory 2.6 A Major Development in Support of the Molecular Hypothesis 2.7 Ions in Solutions: van't Hoff, Arrhenius, Ostwald, and Nernst 2.8 By What Authority Still Only a Hypothesis? Chapter 3. The Historical Bakcground: Brownian Motion 3.1 The Promise of Brownian Motion 3.2 Granular Velocity Measurement: A Failure in Experimentation 3.3 Explaining Granular Velocities: A Failure in Theory-Mediation 3.4 The Problem Reconsidered; The Promise Delivered 3.5 The History in Retrospect Chapter 4. Perrin's Brownian Motion Experiments 4.1 Some Preliminaries 4.2 Perrin's Vertical-Gradient Experiments 4.3 Perrin's Vertical-Gradient Results Re-Examined 4.4 Perrin's Granule-Displacement Experiments: The Two Measures 4.5 Perrin's Granule-Displacement Experiments: Displacement Results 4.6 Perrin's Granule-Displacement Experiments: Diffusion Results 4.7 Perrin's Granule Rotation Experiments 4.8 The Three Different Types of Experiment, Taken Together 4.9 Some Remarks about "Well-Behaved" Theory-Mediated Measurements 4.10 A Critical Assessment of Perrin's Results at the Time Chapter 5. Implications for Molecular-Kinetic Theory 5.1 Testing Molecular-Kinetic Theory: The Kinetic Energy "Test" 5.2 Testing Molecular-Kinetic Theory: Other "Tests" 5.3 Grounding Molecular-Kinetic Theory 5.4 Parallels with Molecular-Kinetic Theory 5.5 Continuity with Molecular-Kinetic Theory 5.6 Continuity from Granule to Liquid Substrate 5.7 A Brief Recap Chapter 6. Converging Values of Avogadro's Number: Perrin's Comparisons 6.1 Some Historical Background 6.2 What Agreeing Measurements? 6.3 Perrin's Comparisons, Individually 6.4 Perrin on the Values # 62 x 1022 6.5 Perrin's Comparisons, Collectively 6.6 "Les Preuves de la Réalité Moléculaire"? 6.7 On Eliminating All Reference to the Invisible 6.8 A Parting Comment, re réalité moléculaire Chapter 7. Our Initial Issues, Revisited 7.1 Conclusions Established About Brownian Motion 7.2 Perrin's Contribution to the New Standing 7.3 The New Standing of Molecular Theory: Ostwald's "Conversion" 7.4 The New Standing of Molecular Theory: In the Aftermath of Solvay 7.5 On the Standing of Hypotheses 7.6 1905-1913 Within the History of Theory-Mediated Measurement Postcript on the Realism-Instrumentalism Debate 1. On the Scientific Literature 2. On Some Key Distinctions 3. On What Has Claim to Being Permanent Appendix: On Ostwald (1889-90), Nernst (1893), and Meyer (1899) Glossary Scientific Terminology Theory-mediated Measurement Terminology Bibliography

Any philosopher hitherto who wishes to take a stand on the relevance of Perrin's studies to the debate about realism will need to take heed of the findings here. All of the publications on the matter that preceded its publication will need to be reconsidered, my own included.