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.

• PrefaceBibliographical Notice Chapter 1. Introduction1.1 Brownian Motion and Molecular Reality: The "Lore"1.2 Two Issues1.3 Challenges to Our Second Issue1.4 Why the Focus So Narrowly on Perrin?1.5 Organization of the Monograph Chapter 2. The Historical Background: Molecular Theory as of 19002.1 On the "Hypothetical" Status of the Molecular Hypothesis2.2 Kinetic Theory as a Means of Gaining Access to Molecules2.3 The Problem Posed by the Specific Heats of Gases2.4 Ostwald on How a Hypothesis Can Become Something More2.5 A Further Dimension of the Dispute over Molecular-Kinetic Theory2.6 A Major Development in Support of the Molecular Hypothesis2.7 Ions in Solutions: van't Hoff, Arrhenius, Ostwald, and Nernst2.8 By What Authority Still Only a Hypothesis? Chapter 3. The Historical Bakcground: Brownian Motion3.1 The Promise of Brownian Motion3.2 Granular Velocity Measurement: A Failure in Experimentation3.3 Explaining Granular Velocities: A Failure in Theory-Mediation3.4 The Problem Reconsidered; The Promise Delivered3.5 The History in Retrospect Chapter 4. Perrin's Brownian Motion Experiments4.1 Some Preliminaries4.2 Perrin's Vertical-Gradient Experiments4.3 Perrin's Vertical-Gradient Results Re-Examined4.4 Perrin's Granule-Displacement Experiments: The Two Measures4.5 Perrin's Granule-Displacement Experiments: Displacement Results4.6 Perrin's Granule-Displacement Experiments: Diffusion Results4.7 Perrin's Granule Rotation Experiments4.8 The Three Different Types of Experiment, Taken Together4.9 Some Remarks about "Well-Behaved" Theory-Mediated Measurements4.10 A Critical Assessment of Perrin's Results at the Time Chapter 5. Implications for Molecular-Kinetic Theory5.1 Testing Molecular-Kinetic Theory: The Kinetic Energy "Test"5.2 Testing Molecular-Kinetic Theory: Other "Tests"5.3 Grounding Molecular-Kinetic Theory5.4 Parallels with Molecular-Kinetic Theory5.5 Continuity with Molecular-Kinetic Theory5.6 Continuity from Granule to Liquid Substrate5.7 A Brief Recap Chapter 6. Converging Values of Avogadro's Number: Perrin's Comparisons6.1 Some Historical Background6.2 What Agreeing Measurements?6.3 Perrin's Comparisons, Individually6.4 Perrin on the Values # 62 x 1022 6.5 Perrin's Comparisons, Collectively6.6 "Les Preuves de la Réalité Moléculaire"?6.7 On Eliminating All Reference to the Invisible6.8 A Parting Comment, re réalité moléculaire Chapter 7. Our Initial Issues, Revisited7.1 Conclusions Established About Brownian Motion7.2 Perrin's Contribution to the New Standing7.3 The New Standing of Molecular Theory: Ostwald's "Conversion"7.4 The New Standing of Molecular Theory: In the Aftermath of Solvay7.5 On the Standing of Hypotheses7.6 1905-1913 Within the History of Theory-Mediated Measurement Postcript on the Realism-Instrumentalism Debate1. On the Scientific Literature2. On Some Key Distinctions3. On What Has Claim to Being Permanent Appendix: On Ostwald (1889-90), Nernst (1893), and Meyer (1899) GlossaryScientific TerminologyTheory-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.