This volume features a critical edition of the recently rediscovered manuscripts written by the French philosopher Louis Couturat (1868-1914).It includes the transcriptions of three of his believed to be lost manuscripts: first the “Cours de Caen: 1898-99” on various systems of symbolic logic, second his lecture at the Collège de France “Histoire de la logique formelle moderne", and third his textbook on mathematical logic. The manuscripts document the early reception of mathematical logic in France and provide insights into the first introduction of the French reader to the work of Gottlob Frege and Bertrand Russell.It is the aim of the editors of this volume to contribute to the history of symbolic logic, particularly the history of its dissemination and its teaching in France. At the same time, the volume contributes to an alternative history and conception of philosophy in which semiotics and concrete mathematical practice stand in focus.The bookis interesting for students and researchers in the history of philosophy, mathematics, and logic.

Louis Couturat (1868–1914) was an outstanding intellectual of the turn of the nineteenth to the twentieth century. He is known for his work in the philosophy of mathematics, for his critical and editorial work on Leibniz, for his attempt to popularise modern logic in France, for his commitment to an international auxiliary language, as well as for his extended correspondence with scholars and mathematicians from Great Britain, the United States, Italy, and Germany. From his correspondence we know of four unpublished manuscripts on logic and its history, which were largely complete and some of which must have been of considerable size. We publish here for the ?rst time in a critical edition the only one of these manuscripts that has been rediscovered: the Traité de Logique algorithmique, presumably written in the years 1899–1901. It is a highly interesting document of the academic reception and popularisation of symbolic logic in France. It provides evidence of the discussions and controversies which accompanied the creation of logic as a new branch of science. At the same time it completes the picture of Couturat’s work, which has been opened up to systematic study by the publication of important parts of his correspondence during the last decade. We append the article on Symbolic Logic of 1902 which Couturat wrote in collaboration with Christine Ladd- Franklin for Baldwin’s Dictionary of Philosophy and Psychology.

This book is a collection of essays on the reception of Leibniz’s thinking in the sciences and in the philosophy of science in the 19th and 20th centuries. Authors studied include C.F. Gauss, Georg Cantor, Kurd Lasswitz, Bertrand Russell, Ernst Cassirer, Louis Couturat, Hans Reichenbach, Hermann Weyl, Kurt Gödel and Gregory Chaitin. In addition, we consider concepts and problems central to Leibniz’s thought and that of the later authors: the continuum, space, identity, number, the infinite and the infinitely small, the projects of a universal language, a calculus of logic, a mathesis universalis etc. The book brings together two fields of research in the history of philosophy and of science (research on Leibniz, and the research concerned with some major developments in the 19th and 20th centuries); it describes how Leibniz’s thought appears in the works of these authors, in order to better understand Leibniz’s influence on contemporary science and philosophy; but it also assesses that reception critically, confronting it in particular with the current state of Leibniz research and with the various editions of his work.

Louis Couturat (1868–1914) was an outstanding intellectual of the turn of the nineteenth to the twentieth century. He is known for his work in the philosophy of mathematics, for his critical and editorial work on Leibniz, for his attempt to popularise modern logic in France, for his commitment to an international auxiliary language, as well as for his extended correspondence with scholars and mathematicians from Great Britain, the United States, Italy, and Germany. From his correspondence we know of four unpublished manuscripts on logic and its history, which were largely complete and some of which must have been of considerable size. We publish here for the ?rst time in a critical edition the only one of these manuscripts that has been rediscovered: the Traité de Logique algorithmique, presumably written in the years 1899–1901. It is a highly interesting document of the academic reception and popularisation of symbolic logic in France. It provides evidence of the discussions and controversies which accompanied the creation of logic as a new branch of science. At the same time it completes the picture of Couturat’s work, which has been opened up to systematic study by the publication of important parts of his correspondence during the last decade. We append the article on Symbolic Logic of 1902 which Couturat wrote in collaboration with Christine Ladd- Franklin for Baldwin’s Dictionary of Philosophy and Psychology.

This book is a collection of essays on the reception of Leibniz’s thinking in the sciences and in the philosophy of science in the 19th and 20th centuries. Authors studied include C.F. Gauss, Georg Cantor, Kurd Lasswitz, Bertrand Russell, Ernst Cassirer, Louis Couturat, Hans Reichenbach, Hermann Weyl, Kurt Gödel and Gregory Chaitin. In addition, we consider concepts and problems central to Leibniz’s thought and that of the later authors: the continuum, space, identity, number, the infinite and the infinitely small, the projects of a universal language, a calculus of logic, a mathesis universalis etc. The book brings together two fields of research in the history of philosophy and of science (research on Leibniz, and the research concerned with some major developments in the 19th and 20th centuries); it describes how Leibniz’s thought appears in the works of these authors, in order to better understand Leibniz’s influence on contemporary science and philosophy; but it also assesses that reception critically, confronting it in particular with the current state of Leibniz research and with the various editions of his work.

During his lifetime, Henri Poincare published three major philosophical books which achieved great success: "La science et l'hypothese" (1902), "La valeur de la science" (1905) and "Science et methode" (1908). After his death in 1913, a fourth volume of his philosophical works was published by his heirs as "Dernieres pensees" (1913). The four books constitute the core of Poincare's philosophic works and were given an ovation by scientific and general public. Around 1919, Gustave Le Bon wrote to Poincare's widow. As the director of the "Bibliotheque de Philosophie Scientifique at Flammarion", he asked her permission to publish a second posthumous volume. "L'Opportunisme scientifique" was intended to be the fifth and final volume of Poincare's philosophical writings. Louis Rougier had elaborated the project, with the collaboration of Gustave Le Bon, and the approval of the philosopher Emile Boutroux and his son Pierre. Because of the reservations of the mathematician's heirs, this book was never published and Dernieres pensees remained his last philosophical book.Nevertheless Poincare's correspondence - which is kept in the Poincare Archives at University Nancy 2 - contains a large amount of documents concerning the project, its justification and the discussions between Louis Rougier and the mathematician's heirs. The aim of this book is to restore this episode, which gives some crucial informations about editorial practices of Poincare and about the posterity of his philosophic thinking.

Ce cinquième volume de la correspondance d’Henri Poincaré rassemble l’ensemble des lettres envoyées par le mathématicien à sa famille durant ses années de formation à l’École polytechnique puis à l’École des mines de Paris. De 1873 à 1878, Poincaré écrit plus de 300 lettres à sa mère, à sa sœur et à son père. Une part importante de cette correspondance concerne ses études pour devenir ingénieur. Poincaré évoque ainsi les différents événements – importants ou anodins – qui ponctuent son parcours de formation dans les deux écoles: les cours et les examens, les voyages d’études en France et à l’étranger, les relations avec les professeurs, les rituels étudiants, la naissance de ses ambitions mathématiques. Cependant, ces lettres de jeunesse permettent également de reconstituer les réseaux familiaux et amicaux de Poincaré ainsi que l’univers socio-culturel dans lequel il évolue dans les années 1870. Elles fourmillent donc de récits pittoresques sur ses visites mondaines,sur ses relations avec sa sœur ou ses amis d’enfance, sur ses loisirs ou sur ses convictions politiques. Ce corpus de lettres est constitué presque intégralement de lettres écrites par Poincaré et leur lecture permet de découvrir un autoportrait inédit et saisissant du futur mathématicien. Il intéressera autant les historiens des mathématiques que les biographes de Poincaré, les historiens de l’enseignement ou le grand public.

Cet ouvrage contient les correspondances actives et passives de Jules Hoüel avec Joseph-Marie De Tilly, Gaston Darboux et Victor-Amédée Le Besgue ainsi qu’une introduction qui se focalise sur la découverte de l’impossibilité de démontrer le postulat des parallèles d’Euclide et l’apparition des premiers exemples de fonctions continues non dérivables.Jules Hoüel (1823-1886) a occupé une place particulière dans les mathématiques en France durant la seconde partie du 19ème siècle. Par ses travaux de traduction et ses recensions, il a vivement contribué à la réception de la géométrie non euclidienne de Bolyai et Lobatchevski ainsi qu’aux débats sur les fondements de l’analyse. Il se situe au centre d’un vaste réseau international de  correspondances en lien avec son rôle de rédacteur pour le Bulletin des sciences mathématiques et astronomiques.

Entre 1881 et 1911, Gösta Mittag-Leffler et Henri Poincaré échangent une correspondance régulière. Elle couvre quasiment la carrière scientifique de Poincaré. On peut distinguer quatre périodes dans cette correspondance: Une première période assez courte permet aux deux mathématiciens de faire connaissance par l’intermédiaire de Hermite; la seconde période est celle, extrêmement féconde, de la création de la revue Acta Mathematica par Mittag-Leffler et de la rédaction par Poincaré des grands mémoires sur les fonctions fuchsiennes; suit la période du concours du Roi de Suède avec de très intéressantes lettres sur la gestion, tant scientifique qu’institutionnelle, de l’erreur de Poincaré dans son mémoire présenté au concours. La dernière période est celle de la "maturité", durant laquelle on voit deux universitaires de renom gérer leur réseau d’obligés et d’élèves, s’occuper de nominations dans diverses académies et de propositions au prix Nobel de Physique. Ce volume est le premier d’une édition commentée de la correspondance de Henri Poincaré. La correspondance est éditée par les Archives – Centre d‘Etudes et de Recherche Henri Poincaré (ACERHP) sous la direction de Gerhard Heinzmann et avec le soutien de l‘Association pour le Développement des Recherches sur les Sciences et Techniques (ADREST). Trois autres tomes sont en cours de préparation: le second sera consacré à la correspondance de Poincaré avec des physiciens, le troisième à celle avec des mathématiciens et le dernier aux échanges administratifs et privés de Poincaré. Cette publication témoignera de l’extraordinaire rayonnement scientifique de Poincaré et de la diversité extrêmement large de ses intérêts. Son objectif est de rendre cette penseé accessible à une audience la plus large possible en montrant ses origines et les traces des tâtonnements qui y ont conduit. Comprendre la genèse de la science [...] estindispensable pour l’intelligence complète de la science elle-même [Poincaré 1902b, p. 153]. Conçus selon les plans historiques et scientifiques les plus stricts, ces volumes intéresseront les enseignants, les chercheurs et les étudiants en mathématiques, physique, histoire et sociologie des sciences, logique ou philosophie ainsi que tous ceux qui s’intéressent à ces disciplines. Le comité éditorial de la correspondance de Poincaré a choisi de publier les correspondances dans leur intégralité et commentées s’il y avait lieu.

During his lifetime, Henri Poincare published three major philosophical books which achieved great success: "La science et l'hypothese" (1902), "La valeur de la science" (1905) and "Science et methode" (1908). After his death in 1913, a fourth volume of his philosophical works was published by his heirs as "Dernieres pensees" (1913). The four books constitute the core of Poincare's philosophic works and were given an ovation by scientific and general public. Around 1919, Gustave Le Bon wrote to Poincare's widow. As the director of the "Bibliotheque de Philosophie Scientifique at Flammarion", he asked her permission to publish a second posthumous volume. "L'Opportunisme scientifique" was intended to be the fifth and final volume of Poincare's philosophical writings. Louis Rougier had elaborated the project, with the collaboration of Gustave Le Bon, and the approval of the philosopher Emile Boutroux and his son Pierre. Because of the reservations of the mathematician's heirs, this book was never published and Dernieres pensees remained his last philosophical book.Nevertheless Poincare's correspondence - which is kept in the Poincare Archives at University Nancy 2 - contains a large amount of documents concerning the project, its justification and the discussions between Louis Rougier and the mathematician's heirs. The aim of this book is to restore this episode, which gives some crucial informations about editorial practices of Poincare and about the posterity of his philosophic thinking.

L'intérêt que portait Henri Poincaré (1854-1912) à des questions d'ordre physique a été durable et profond; elle couvre presque toute sa carrière, et marque l'histoire de la physique tout au long du 20ème siècle. Sa correspondance avec cinquante-et-un physiciens, quatre chimistes, et cinq ingénieurs commence dès 1879, lorsqu'il s'engage activement dans la recherche scientifique. Elle est rythmée par des grandes découvertes d'ordre expérimental, instrumental, et théorique. Henri Poincaré, while well-known as the most brilliant mathematician at the close of the 19th century, is also a founder of 20th-century physics, in virtue of his fundamental contributions to Maxwell's theory, systems dynamics, electron theory, relativity and quantum theory. These subjects and others are discussed in this critical edition of his correspondence with sixty physicists, chemists, and engineers.

The lettersin this volume cover Poincaré's multifaceted career in astronomy in itsentirety, extending from the time of his first publications in 1880 to the endof his life in 1912. At a tender age, Poincaré established his authority inquestions of celestial mechanics, and his views were soon sought after on avast array of questions by the leading astronomers and geodesists of his time,including C.V.L. Charlier, G.H. Darwin, H. Faye, F.R. Helmert, G. W. Hill, A.Lindstedt, A.M. Liapunov, N. Lockyer, S. Newcomb, K. Schwarzschild, and F.Tisserand. Poincaré and his correspondents take up topics ranging from thethree-body problem and perturbation theory to the determination of the geoideand the equilibrium figures of rotating fluid masses. The volume also shedslight on Poincaré's three terms as president of the Bureau of Longitudes, wherehe guided French astronomy and geodesy through ambitious projects, such as themeasurement of an arc of meridian near Quito.------Les lettres du troisième volume de la Correspondance de Poincaré scandent toute son œuvre astronomique, allant de ses premiers mémoires sur les courbes définies par une équation différentielle (1881), jusqu'aux analyses des hypothèses cosmogoniques (1911). Encore très jeune, Poincaré s'est fait remarquer pour sa maîtrise des questions de la mécanique céleste, de tel sorte que les astronomes et les géodésiens l'ont souvent interpellé, y compris O. Callandreau, C.V.L. Charlier, G.H. Darwin, F.R. Helmert, A. Lindstedt, A.M. Lyapunov, Simon Newcomb, Karl Schwarzschild et F. Tisserand.Avec ses correspondants, Poincaré abordaient les questions principales de l'astronomie mathématique, du célèbre problème des trois corps à la théorie des perturbations et aux figures d'équilibre des masses fluides en rotation. La correspondance de Poincaré éditée et annotée dans ce volume concerne, au-delà des mémoires mathématiques, l'activité de Poincaré en tant que Professeurd'astronomie mathématique et de mécanique céleste à la Sorbonne, rédacteur en chef duBulletin astronomique, et membre du Bureau des longitudes, que Poincaré a présidé à trois reprises. Sa correspondance illumine, dans ce dernier cadre, la réalisation de la mesure d'un arc de méridien à Quito, et le règlement d'un différend franco-brittanique à propos de la différence de longitude entre Greenwich et Paris.

Indispensable for understanding Henri Poincaré's vast activity in the mathematical sciences. Provides new sources revealing Poincaré's involvement as president of the "Commission permanente du Répertoire bibliographique des sciences mathématiques" as an actor in the "Dreyfus Affair," and on his links with the editors of the major mathematical journals.The letters, many of which are unpublished, are fully annotated with an emphasis on the academic, cultural and technical contexts. An introduction underlines the lessons that can be drawn from the reading of these correspondences on Poincaré's position in the mathematical and academic communities. Three indexes facilitate the reading.Le volume de la correspondance de Poincaré consacré à ses échanges avec les mathématiciens permet de suivre son investissement dans le champ des sciences mathématiques de ses débuts comme étudiant brillant et prometteur préparant une thèse jusqu’à ses derniers jours, où devenu une icone pourla communauté mathématique depuis de longues années, sa correspondance traduit autant son activité dans la recherche que son implication dans les questions académiques, institutionnelles et organisationnelles. Les questions liées à la théorie des équations différentielles et l’entreprise du Répertoire bibliographique des sciences mathématiques ont suscité une activité épistolaire particulièrement sensible par le nombre de lettres qui y font allusion et par la diversité des correspondants qui abordent les questions de bibliographie mathématique. Les correspondances sont aussi l’occasion de multiples partages d’informations mathématiques, académiques et éditoriales.

This volume features a critical edition of the recently rediscovered manuscripts written by the French philosopher Louis Couturat (1868-1914).It includes the transcriptions of three of his believed to be lost manuscripts: first the “Cours de Caen: 1898-99” on various systems of symbolic logic, second his lecture at the Collège de France “Histoire de la logique formelle moderne", and third his textbook on mathematical logic. The manuscripts document the early reception of mathematical logic in France and provide insights into the first introduction of the French reader to the work of Gottlob Frege and Bertrand Russell.It is the aim of the editors of this volume to contribute to the history of symbolic logic, particularly the history of its dissemination and its teaching in France. At the same time, the volume contributes to an alternative history and conception of philosophy in which semiotics and concrete mathematical practice stand in focus.The bookis interesting for students and researchers in the history of philosophy, mathematics, and logic.

Louis Couturat (1868–1914) was an outstanding intellectual of the turn of the nineteenth to the twentieth century. He is known for his work in the philosophy of mathematics, for his critical and editorial work on Leibniz, for his attempt to popularise modern logic in France, for his commitment to an international auxiliary language, as well as for his extended correspondence with scholars and mathematicians from Great Britain, the United States, Italy, and Germany. From his correspondence we know of four unpublished manuscripts on logic and its history, which were largely complete and some of which must have been of considerable size. We publish here for the ?rst time in a critical edition the only one of these manuscripts that has been rediscovered: the Traité de Logique algorithmique, presumably written in the years 1899–1901. It is a highly interesting document of the academic reception and popularisation of symbolic logic in France. It provides evidence of the discussions and controversies which accompanied the creation of logic as a new branch of science. At the same time it completes the picture of Couturat’s work, which has been opened up to systematic study by the publication of important parts of his correspondence during the last decade. We append the article on Symbolic Logic of 1902 which Couturat wrote in collaboration with Christine Ladd- Franklin for Baldwin’s Dictionary of Philosophy and Psychology.

This book is a collection of essays on the reception of Leibniz’s thinking in the sciences and in the philosophy of science in the 19th and 20th centuries. Authors studied include C.F. Gauss, Georg Cantor, Kurd Lasswitz, Bertrand Russell, Ernst Cassirer, Louis Couturat, Hans Reichenbach, Hermann Weyl, Kurt Gödel and Gregory Chaitin. In addition, we consider concepts and problems central to Leibniz’s thought and that of the later authors: the continuum, space, identity, number, the infinite and the infinitely small, the projects of a universal language, a calculus of logic, a mathesis universalis etc. The book brings together two fields of research in the history of philosophy and of science (research on Leibniz, and the research concerned with some major developments in the 19th and 20th centuries); it describes how Leibniz’s thought appears in the works of these authors, in order to better understand Leibniz’s influence on contemporary science and philosophy; but it also assesses that reception critically, confronting it in particular with the current state of Leibniz research and with the various editions of his work.

Louis Couturat (1868–1914) was an outstanding intellectual of the turn of the nineteenth to the twentieth century. He is known for his work in the philosophy of mathematics, for his critical and editorial work on Leibniz, for his attempt to popularise modern logic in France, for his commitment to an international auxiliary language, as well as for his extended correspondence with scholars and mathematicians from Great Britain, the United States, Italy, and Germany. From his correspondence we know of four unpublished manuscripts on logic and its history, which were largely complete and some of which must have been of considerable size. We publish here for the ?rst time in a critical edition the only one of these manuscripts that has been rediscovered: the Traité de Logique algorithmique, presumably written in the years 1899–1901. It is a highly interesting document of the academic reception and popularisation of symbolic logic in France. It provides evidence of the discussions and controversies which accompanied the creation of logic as a new branch of science. At the same time it completes the picture of Couturat’s work, which has been opened up to systematic study by the publication of important parts of his correspondence during the last decade. We append the article on Symbolic Logic of 1902 which Couturat wrote in collaboration with Christine Ladd- Franklin for Baldwin’s Dictionary of Philosophy and Psychology.

This book is a collection of essays on the reception of Leibniz’s thinking in the sciences and in the philosophy of science in the 19th and 20th centuries. Authors studied include C.F. Gauss, Georg Cantor, Kurd Lasswitz, Bertrand Russell, Ernst Cassirer, Louis Couturat, Hans Reichenbach, Hermann Weyl, Kurt Gödel and Gregory Chaitin. In addition, we consider concepts and problems central to Leibniz’s thought and that of the later authors: the continuum, space, identity, number, the infinite and the infinitely small, the projects of a universal language, a calculus of logic, a mathesis universalis etc. The book brings together two fields of research in the history of philosophy and of science (research on Leibniz, and the research concerned with some major developments in the 19th and 20th centuries); it describes how Leibniz’s thought appears in the works of these authors, in order to better understand Leibniz’s influence on contemporary science and philosophy; but it also assesses that reception critically, confronting it in particular with the current state of Leibniz research and with the various editions of his work.

During his lifetime, Henri Poincare published three major philosophical books which achieved great success: "La science et l'hypothese" (1902), "La valeur de la science" (1905) and "Science et methode" (1908). After his death in 1913, a fourth volume of his philosophical works was published by his heirs as "Dernieres pensees" (1913). The four books constitute the core of Poincare's philosophic works and were given an ovation by scientific and general public. Around 1919, Gustave Le Bon wrote to Poincare's widow. As the director of the "Bibliotheque de Philosophie Scientifique at Flammarion", he asked her permission to publish a second posthumous volume. "L'Opportunisme scientifique" was intended to be the fifth and final volume of Poincare's philosophical writings. Louis Rougier had elaborated the project, with the collaboration of Gustave Le Bon, and the approval of the philosopher Emile Boutroux and his son Pierre. Because of the reservations of the mathematician's heirs, this book was never published and Dernieres pensees remained his last philosophical book.Nevertheless Poincare's correspondence - which is kept in the Poincare Archives at University Nancy 2 - contains a large amount of documents concerning the project, its justification and the discussions between Louis Rougier and the mathematician's heirs. The aim of this book is to restore this episode, which gives some crucial informations about editorial practices of Poincare and about the posterity of his philosophic thinking.

Ce cinquième volume de la correspondance d’Henri Poincaré rassemble l’ensemble des lettres envoyées par le mathématicien à sa famille durant ses années de formation à l’École polytechnique puis à l’École des mines de Paris. De 1873 à 1878, Poincaré écrit plus de 300 lettres à sa mère, à sa sœur et à son père. Une part importante de cette correspondance concerne ses études pour devenir ingénieur. Poincaré évoque ainsi les différents événements – importants ou anodins – qui ponctuent son parcours de formation dans les deux écoles: les cours et les examens, les voyages d’études en France et à l’étranger, les relations avec les professeurs, les rituels étudiants, la naissance de ses ambitions mathématiques. Cependant, ces lettres de jeunesse permettent également de reconstituer les réseaux familiaux et amicaux de Poincaré ainsi que l’univers socio-culturel dans lequel il évolue dans les années 1870. Elles fourmillent donc de récits pittoresques sur ses visites mondaines,sur ses relations avec sa sœur ou ses amis d’enfance, sur ses loisirs ou sur ses convictions politiques. Ce corpus de lettres est constitué presque intégralement de lettres écrites par Poincaré et leur lecture permet de découvrir un autoportrait inédit et saisissant du futur mathématicien. Il intéressera autant les historiens des mathématiques que les biographes de Poincaré, les historiens de l’enseignement ou le grand public.

Cet ouvrage contient les correspondances actives et passives de Jules Hoüel avec Joseph-Marie De Tilly, Gaston Darboux et Victor-Amédée Le Besgue ainsi qu’une introduction qui se focalise sur la découverte de l’impossibilité de démontrer le postulat des parallèles d’Euclide et l’apparition des premiers exemples de fonctions continues non dérivables.Jules Hoüel (1823-1886) a occupé une place particulière dans les mathématiques en France durant la seconde partie du 19ème siècle. Par ses travaux de traduction et ses recensions, il a vivement contribué à la réception de la géométrie non euclidienne de Bolyai et Lobatchevski ainsi qu’aux débats sur les fondements de l’analyse. Il se situe au centre d’un vaste réseau international de  correspondances en lien avec son rôle de rédacteur pour le Bulletin des sciences mathématiques et astronomiques.

Entre 1881 et 1911, Gösta Mittag-Leffler et Henri Poincaré échangent une correspondance régulière. Elle couvre quasiment la carrière scientifique de Poincaré. On peut distinguer quatre périodes dans cette correspondance: Une première période assez courte permet aux deux mathématiciens de faire connaissance par l’intermédiaire de Hermite; la seconde période est celle, extrêmement féconde, de la création de la revue Acta Mathematica par Mittag-Leffler et de la rédaction par Poincaré des grands mémoires sur les fonctions fuchsiennes; suit la période du concours du Roi de Suède avec de très intéressantes lettres sur la gestion, tant scientifique qu’institutionnelle, de l’erreur de Poincaré dans son mémoire présenté au concours. La dernière période est celle de la "maturité", durant laquelle on voit deux universitaires de renom gérer leur réseau d’obligés et d’élèves, s’occuper de nominations dans diverses académies et de propositions au prix Nobel de Physique. Ce volume est le premier d’une édition commentée de la correspondance de Henri Poincaré. La correspondance est éditée par les Archives – Centre d‘Etudes et de Recherche Henri Poincaré (ACERHP) sous la direction de Gerhard Heinzmann et avec le soutien de l‘Association pour le Développement des Recherches sur les Sciences et Techniques (ADREST). Trois autres tomes sont en cours de préparation: le second sera consacré à la correspondance de Poincaré avec des physiciens, le troisième à celle avec des mathématiciens et le dernier aux échanges administratifs et privés de Poincaré. Cette publication témoignera de l’extraordinaire rayonnement scientifique de Poincaré et de la diversité extrêmement large de ses intérêts. Son objectif est de rendre cette penseé accessible à une audience la plus large possible en montrant ses origines et les traces des tâtonnements qui y ont conduit. Comprendre la genèse de la science [...] estindispensable pour l’intelligence complète de la science elle-même [Poincaré 1902b, p. 153]. Conçus selon les plans historiques et scientifiques les plus stricts, ces volumes intéresseront les enseignants, les chercheurs et les étudiants en mathématiques, physique, histoire et sociologie des sciences, logique ou philosophie ainsi que tous ceux qui s’intéressent à ces disciplines. Le comité éditorial de la correspondance de Poincaré a choisi de publier les correspondances dans leur intégralité et commentées s’il y avait lieu.

During his lifetime, Henri Poincare published three major philosophical books which achieved great success: "La science et l'hypothese" (1902), "La valeur de la science" (1905) and "Science et methode" (1908). After his death in 1913, a fourth volume of his philosophical works was published by his heirs as "Dernieres pensees" (1913). The four books constitute the core of Poincare's philosophic works and were given an ovation by scientific and general public. Around 1919, Gustave Le Bon wrote to Poincare's widow. As the director of the "Bibliotheque de Philosophie Scientifique at Flammarion", he asked her permission to publish a second posthumous volume. "L'Opportunisme scientifique" was intended to be the fifth and final volume of Poincare's philosophical writings. Louis Rougier had elaborated the project, with the collaboration of Gustave Le Bon, and the approval of the philosopher Emile Boutroux and his son Pierre. Because of the reservations of the mathematician's heirs, this book was never published and Dernieres pensees remained his last philosophical book.Nevertheless Poincare's correspondence - which is kept in the Poincare Archives at University Nancy 2 - contains a large amount of documents concerning the project, its justification and the discussions between Louis Rougier and the mathematician's heirs. The aim of this book is to restore this episode, which gives some crucial informations about editorial practices of Poincare and about the posterity of his philosophic thinking.

L'intérêt que portait Henri Poincaré (1854-1912) à des questions d'ordre physique a été durable et profond; elle couvre presque toute sa carrière, et marque l'histoire de la physique tout au long du 20ème siècle. Sa correspondance avec cinquante-et-un physiciens, quatre chimistes, et cinq ingénieurs commence dès 1879, lorsqu'il s'engage activement dans la recherche scientifique. Elle est rythmée par des grandes découvertes d'ordre expérimental, instrumental, et théorique. Henri Poincaré, while well-known as the most brilliant mathematician at the close of the 19th century, is also a founder of 20th-century physics, in virtue of his fundamental contributions to Maxwell's theory, systems dynamics, electron theory, relativity and quantum theory. These subjects and others are discussed in this critical edition of his correspondence with sixty physicists, chemists, and engineers.

The lettersin this volume cover Poincaré's multifaceted career in astronomy in itsentirety, extending from the time of his first publications in 1880 to the endof his life in 1912. At a tender age, Poincaré established his authority inquestions of celestial mechanics, and his views were soon sought after on avast array of questions by the leading astronomers and geodesists of his time,including C.V.L. Charlier, G.H. Darwin, H. Faye, F.R. Helmert, G. W. Hill, A.Lindstedt, A.M. Liapunov, N. Lockyer, S. Newcomb, K. Schwarzschild, and F.Tisserand. Poincaré and his correspondents take up topics ranging from thethree-body problem and perturbation theory to the determination of the geoideand the equilibrium figures of rotating fluid masses. The volume also shedslight on Poincaré's three terms as president of the Bureau of Longitudes, wherehe guided French astronomy and geodesy through ambitious projects, such as themeasurement of an arc of meridian near Quito.------Les lettres du troisième volume de la Correspondance de Poincaré scandent toute son œuvre astronomique, allant de ses premiers mémoires sur les courbes définies par une équation différentielle (1881), jusqu'aux analyses des hypothèses cosmogoniques (1911). Encore très jeune, Poincaré s'est fait remarquer pour sa maîtrise des questions de la mécanique céleste, de tel sorte que les astronomes et les géodésiens l'ont souvent interpellé, y compris O. Callandreau, C.V.L. Charlier, G.H. Darwin, F.R. Helmert, A. Lindstedt, A.M. Lyapunov, Simon Newcomb, Karl Schwarzschild et F. Tisserand.Avec ses correspondants, Poincaré abordaient les questions principales de l'astronomie mathématique, du célèbre problème des trois corps à la théorie des perturbations et aux figures d'équilibre des masses fluides en rotation. La correspondance de Poincaré éditée et annotée dans ce volume concerne, au-delà des mémoires mathématiques, l'activité de Poincaré en tant que Professeurd'astronomie mathématique et de mécanique céleste à la Sorbonne, rédacteur en chef duBulletin astronomique, et membre du Bureau des longitudes, que Poincaré a présidé à trois reprises. Sa correspondance illumine, dans ce dernier cadre, la réalisation de la mesure d'un arc de méridien à Quito, et le règlement d'un différend franco-brittanique à propos de la différence de longitude entre Greenwich et Paris.

Indispensable for understanding Henri Poincaré's vast activity in the mathematical sciences. Provides new sources revealing Poincaré's involvement as president of the "Commission permanente du Répertoire bibliographique des sciences mathématiques" as an actor in the "Dreyfus Affair," and on his links with the editors of the major mathematical journals.The letters, many of which are unpublished, are fully annotated with an emphasis on the academic, cultural and technical contexts. An introduction underlines the lessons that can be drawn from the reading of these correspondences on Poincaré's position in the mathematical and academic communities. Three indexes facilitate the reading.Le volume de la correspondance de Poincaré consacré à ses échanges avec les mathématiciens permet de suivre son investissement dans le champ des sciences mathématiques de ses débuts comme étudiant brillant et prometteur préparant une thèse jusqu’à ses derniers jours, où devenu une icone pourla communauté mathématique depuis de longues années, sa correspondance traduit autant son activité dans la recherche que son implication dans les questions académiques, institutionnelles et organisationnelles. Les questions liées à la théorie des équations différentielles et l’entreprise du Répertoire bibliographique des sciences mathématiques ont suscité une activité épistolaire particulièrement sensible par le nombre de lettres qui y font allusion et par la diversité des correspondants qui abordent les questions de bibliographie mathématique. Les correspondances sont aussi l’occasion de multiples partages d’informations mathématiques, académiques et éditoriales.