L’idéalisme britannique est un mouvement qui a dominé les universités britanniques pendant une cinquantaine d’années à la fin du xixe siècle et au début du xxe siècle, mais qui est passé presque totalement inaperçu dans le monde francophone. Rejetés en bloc par les philosophes analytiques, ces auteurs ont aussi été ignorés pendant longtemps dans leur pays, mais certains d’entre eux, notamment Bradley et Collingwood, jouissent d’un regain d’intérêt à la faveur d’un renouveau des études sur les origines de la philosophie (...) analytique. Ce texte est une introduction à l’idéalisme britannique, qui retrace, dans une première partie plus historique, les grandes lignes de sa genèse, son développement et son déclin. Dans une deuxième partie, nous donnons quelques arguments en faveur d’une étude plus approfondie de ce mouvement.British Idealism is a philosophical movement that dominated British universities , for fifty years around the turn from the XIXth to the XXth century, but it went largely unnoticed in the French-speaking world. Condemned by analytic philosophers, these authors were also ignored in their own country, but some of them, notably Bradley and Collingwood, are now enjoying a newly found popularity within the larger trend towards a study of the origins of analytic philosophy. This text is an introduction to British Idealism that plots, in an historical first part, the outlines of its rise, development and decline. In the second part, we provide reasons for further studies of this movement. (shrink)

Extension is probably the most general natural property. Is it a fundamental property? Leibniz claimed the answer was no, and that the structureless intuition of extension concealed more fundamental properties and relations. This paper follows Leibniz's program through Herbart and Riemann to Grassmann and uses Grassmann's algebra of points to build up levels of extensions algebraically. Finally, the connection between extension and measurement is considered.

The Calcolo geometrico (1888) seems to have been a turning point in the scientific career of Giuseppe Peano (1858?1932) because with this book he started publishing in logic. Looking for motivations of his early interests in the field one is naturally led to investigate the background of that book. Besides his previous work in mathematical analysis, methods and results of some Italian mathematicians and?above all?the spread of Grassmann's theories in Italy played a significant role: this point seems to have been (...) often underestimated by the historians of the subject. The connections between Calcolo geometrico and other related areas are also discussed. Peano's handwritten remarks and references taken from his own working copy of the Calcolo geometrico constitute the appendix of the paper. ?Simbolismo da alas ad mente de homo? (Peano 1913, 390). (shrink)

This paper develops some respects in which the philosophy of mathematics can fruitfully be informed by mathematical practice, through examining Frege's Grundlagen in its historical setting. The first sections of the paper are devoted to elaborating some aspects of nineteenth century mathematics which informed Frege's early work. (These events are of considerable philosophical significance even apart from the connection with Frege.) In the middle sections, some minor themes of Grundlagen are developed: the relationship Frege envisions between arithmetic and geometry and (...) the way in which the study of reasoning is to illuminate this. In the final section, it is argued that the sorts of issues Frege attempted to address concerning the character of mathematical reasoning are still in need of a satisfying answer. (shrink)

1. Does Hegel’s The Science of Logic (Hegel 2010) have any relation to or relevance for what is now known as ‘the science of logic’? Here a negative answer is as likely to be endorsed by many conte...

The mathematical and epistemological origins of Hermann Graßmann’s innovative work have always attracted the interest of mathematicians and historians. Since Friedrich Engel’s biography, a favourite source for these interpretations has been two curriculum vitae, which were, however, only known from several excerpts. The complete texts are edited here for the first time. They are presented and commented on in their respective contexts, namely the examinations required for a career as Gymnasium teacher and as Protestant pastor. Graßmann’s relations to Schleiermacher’s theology (...) and to his philosophy, as well as Graßmann’s philosophical and mathematical motivations, are discussed in the light of these two documents. (shrink)

Hermann Grassmann's Ausdehnungslehre of 1844 and his Lehrbuch der Arithmetik of 1861 are landmark works in mathematics; the former not only developed new mathematical fields but also both contributed to the setting of modern standards of rigor. Their very modernity, however, may obscure features of Grassmann's view of the foundations of mathematics that were not adopted since. Grassmann gave a key role to the learning of mathematics that affected his method of presentation, including his emphasis on making initial assumptions explicit. (...) In order to better understand this less well-known aspect of his work it will help to examine why some commentators have overlooked his theme of unifying logic, pedagogy and foundations, while others have recognised it. (shrink)

The celebrated “creation” of transfinite set theory by Georg Cantor has been studied in detail by historians of mathematics. However, it has generally been overlooked that his research program cannot be adequately explained as an outgrowth of the mainstream mathematics of his day. We review the main extra-mathematical motivations behind Cantor's very novel research, giving particular attention to a key contribution, the Grundlagen (Foundations of a general theory of sets) of 1883, where those motives are articulated in some detail. Evidence (...) from other publications and correspondence is pulled out to provide clarification and a detailed interpretation of those ideas and their impact upon Cantor's research. Throughout the paper, a special effort is made to place Cantor's scientific undertakings within the context of developments in German science and philosophy at the time (philosophers such as Trendelenburg and Lotze, scientists like Weber, Riemann, Vogt, Haeckel), and to reflect on the German intellectual atmosphere during the nineteenth century. (shrink)

The life and work of Hermann Günther Graßmann (1809–1877) attract not only ever again the attention of mathematicians, mathematical historians and those interested in the history of mathematics, they constitute also a challenge for the methodology of historiographical research. This challenge persists since Friedrich Engel’s biography of 1911; there, two sources were presented and interpreted in a not legitimate manner which even mislead since then various scholars. This paper faces the intricate task to unravel not only the methodological shortcomings of (...) Engel’s biography, but also to re-assess the misinterpretations – particularly of alleged influences on Graßmann’s approaches – induced by Engel’s misleading claims. Based upon broader historically contextualised analyses of Graßmann’s innovative elements in his theory of extension and upon new primary sources for his student times at the Gymnasium and Berlin University, the paper presents a novel assessment of Graßmann’s approaches. (shrink)