Pierre Duhem and Neo-Thomist Interpretations of Physical Science (Ph.D. Thesis, 2000, Martin Hilbert, Institute for the History and Philosophy of Science and Technology, University of Toronto) In 1879, Pope Leo XI11 demanded that Catholic philosophers and theologians adopt scholastic philosophy and especially Thomism in their studies and teaching. Although not primarily abou? science, the encyclical Aetemi Park expressed the hope that scholastic philosophy won!d be a means to understand and even to further science. The thesis examines how neo-Thomists in France and Belgium tried to understand contemporary physical science from the time of the papal mandate to the outbreak of the First World War. These geographical and temporal limits coincide with the immediate sphere of influence of Pierre Duhem (1861-1916), the well- known Catholic physicist, philosopher of science, and historian of science. After putting Aetemi Patris into historical context and focusing both on its own agenda with regard to the philosophy of science and on the challenges that it faced in a scientistic climate, the thesis identifies the major centres of neo-Thomism in the two countries and shows that Duhem was historically connected to all of them. Neo- Thomists were especially determined to re-establish hylomorphism by arguing that mechanical theories of the universe were deficient. Duhem too critiqued mechanism; but his criticism and agenda differed from that of the self-proclaimed neo-Thomists, by arguing that physical theory is not a metaphysical explanation. The thesis first examines the relation between physics and metaphysics through case studies of contemporary debates into which Duhem also entered: human freedom, creation in time, and the proof for the existence of God the Prime Mover. A more theoretical look at the relation shows both that Duhem developed some of his ideas in the philosophy of science in response to neo-Thomist criticism and that his thought in iii turn influenced some leading figures in the movement. It is argued that Jacques Maritain's Distinguer pour unir depends heavily albeit unconsciously on Duhem's work. This proves that Duhem's thought is compatible with one influential school of neo-Thomism and even contributed to its development. The thesis concludes by making the necessary distinctions to counter arguments that Duhem was hostile to the neo-Thomist enterprise on account of his Pascalian inspiration, his friendship with Maurice Blondel, and his panning of Thomas in the Sysdme du monde. Table of Abbreviations vi Acknowledgements vii Introduction 1 Chapter 1 Towards a Renewed Harmony of Faith and Reason in an Age of Science: The Encyclical Aeterni Patris I. Dangerous philosophies: the Magisterium as via negativa 2. The road back to Thomas 3. Aeterni Patris: the wisdom of the ages 4. T/tomism: a brief sketch 5. Aeterni Patris: into a hostile world Chapter 2 Thomism and Science: The Culture in France and Belgium in Duhem's Era I. Soci6ti scientifique de Bmelles 2. Institut supirieur de philosophie: Louvain 3. Imtitut cat/zolique de Paris 4. Soci6t6 de Saint-Thomas d'Aquin 5. Revue de pltilosopltie 6. Revue thomiste Z International Catholic Scientific Congresses 8. Pierre Duhem: at the centre of neo-T/zomist debates A ~atterof Form: Neo-Thomist and Duhemian Criticisms of Modern Physical Science I. Dullem and plzysical tkeoy: an introduction 2. Hylomorphism: an introduction 3. Hylomorphism and mechanism 4. Neo-Thomist views of dynamism and energetics k Dynamism B. Energetics 5. Hylomorphism in light of furtlter developments in physics 6. Dukem's criticim of chemical atomism and of rnec/zanisin 7. Dultem and neo-Thomists: some essential differences Chapter 4 Physics and Metaphysics: Freedom, Creation, and God 1. Human liberty and the first law of thermodynamics A Science as threat to freedom: popular arguments and preliminary notions B. First law of thermodynamics: the shackles of freedom C. Libertas ex machina D. Neo-Thomist reconciliations of physics and freedom E. Duhem on physical determinism 2. Physics and the eterniv of the world A. Creation er nihilo: a dogma of the Christian Faith B. Carbonnelle and the newly developed arguments from science C. Sertillanges and the prudence of Thomas D. Duhem: physics and the Great Year 3. Physics and the existence of God: the Prime Mover argument A. Many ways to the Creator B. The Prime Mover and inertia C. Duhem and the prima via 4. Conclusion: the independence of physics and metaphysics Chapter 5 Towards a Neo-Thomist Philosophy of Science I. Reactions to Duhem's early papers in the Revue des questions scientifiques 2. Duhern at the Congress in Brussels 3. Jean Bullioc: 'un des braves gens' 4. The Fribourg Congress: Andre' de la Barre, s.j. 5. Duhem in Louvain: a much studied pldosopher of science 6. Further inroads: the Dominicans 7. Jacques Maritairr Chapter 6 Sed Contra: Some Necessary Distinctions I. Pascalian inspirations 2. Blonde1 and modernism: sotne Duhemian observations 3. Duhem on Saint T/zomas Aquinas 4. Conclusion Appendix Pierre Duhem: A Biographical Sketch List of Archival Sources Bibliography Table of Abbreviations Aim and Structure of Pltysical Theory Annales de philosophie chritienne ArchAcSci Archives of the AcadCmie des Sciences in Pa% ArchICP Archives of the Institut catholique de Paris Archives of the Dominican library, Le Saulchoir, Paris Revue de philosophie Rwue des questions scientifiques Revue tl~omiste SiancesSSTA This is the standard title for the minutes of the meetings of the SociCtC de Saint-Thomas d'Aquin in Paris. The minutes were published in the AnnPhilChr. The standard reference to these minutes is SiancesSSTA, date, AnnPhilCllr, vol (year), PP. vii Acknowledgements Although I am gratehi to many, I will only mention those who helped directly and significantly in my research with the exception of my Oratorian confreres, who have each lightened some of my pastoral work-load, and of Jacques and Michele Vauthier, without whose generosity I would never have been able to stay in Paris for two months. I would like to thank: Trevor Levere and Sungook Hong for their direction as co-supervisors of the thesis; Stanley Jaki, for his helpful telephone conversations; Henry Donneaud and his Dominican confreres in Toulouse, for their hospitality and use of their library, and for prompt answers to questions I forgot to ask while in France; Jean-Francois Stoffel, for his thesis and bibliography on Duhem, for his transcriptions of some of Duhem's correspondence, as well as for his hospitality in Louvain-la-Neuve, insightful conversations, and his introducing me to Dominique Lambert; Charles Courtoy and especially Dorninique Lambert, both of Namur, for photocopying much valuable archival information on the Soci&ttscientifique de Bruxelles; Andrt Duval, for allowing me to photocopy Duhem's letters to Gardeil, which are in the Dominicans' library at Le Saulchoir, Paris; Philippe Ploix, the Archdiocesan Archivist in Paris, for providing me with many gems, such as the letters from Duhem to Pautonnier; Sister Abel and Jean-Baptiste Lebigue at the Institut catholique de Paris for cheerfully ferreting out archives on Bulliot, Peillaube, and others at the Institut; Pbre UAhelec, for allowing me access to the Marist archives; Francois Beretta, for sharing his surmises on the Socittt Saint Thomas d'Aquin; the archivists at the Acadtmie des Sciences in Paris; Fr Daniel Utrecht, for his proofreading; Fr Paul Pearson, for passing me notes about medieval physics; and SSHRC for four years of financial support under award number 752-95-2106. INTRODUCTION La pensee de Duhem ne mtrite pas une thbse. - Frangou Rlrrso, s.j.' In 1964, Fran~oisRusso advised Joseph O'Malley that the thought of Pierre Duhem (1861-1916) was not worth a thesis. His negative assessment, however, discouraged neither O'Malley nor a significant number of other historians and philosophers, for several major works and theses, and numerous articles, have been written in the last thirty-five years on Duhem and on various aspects of his work as physicist, philosopher of science, and historian of science. Jean-Franyois Stoffel, in his recent doctoral dissertation, has shown that most of the continuing interest in Duhem has focused on his philosophical (30%) and historical (23%) achievement and on the 'Duhem-Quine thesis' (22%). He notes that only 4% of the works have addressed Duhem as a Christian, and only 1% have made significant use of archival materials.' There is no doubt that the 'Duhem-Quine thesis' is important to claims made on behalf of the sociology of scientific knowledge, but it would be as wrong to see in Duhem a partisan of SSK as it was in the past to group him among empirical positivists. Duhem's holism is a much more nuanced position that may require a class of its own. Nevertheless, scholars have attempted to capture his thought in one of the better known categories." Stanley Jaki, for example, has said that 'while From a letter, posted in December 1964, from Russo to Joseph O'Malley who at the time was witing a thesis on 'Material Being and Scientific Knowledge According to Pierre Duhem'. See Stanley Jaki, Reluctanr Heroine: nte Life and Work of Hi12ne Duhern (Edinburgh: Scottish Academic Press, 1992), p. 264. Jaki notes that the words were underlined for emphasis. Jean-Fransois Stoffel, 'Entre projet scientifique et projet apologClique, le phtnomdnalisme probltmatique de Pierre Duhem' (Ph. D. dissertation, 1998, FacultC des sciences philosophiques: lnstitut superieur de philosophie: Universite