Much of the mathematics with which Felix Klein and Sophus Lie are now associated (Klein’s Erlangen Program and Lie’s theory of transformation groups) is rooted in ideas they developed in their early work: the consideration of geometric objects or properties preserved by systems of transformations. As early as 1870, Lie studied particular examples of what he later called contact transformations, which preserve tangency and which came to play a crucial role in his systematic study of transformation groups and differential equations. (...) This note examines Klein’s efforts in the 1870s to interpret contact transformations in terms of connexes and traces that interpretation (which included a false assumption) over the decades that follow. The analysis passes from Klein’s letters to Lie through Lindemann’s edition of Clebsch’s lectures on geometry in 1876, Lie’s criticism of it in his treatise on transformation groups in 1893, and the careful development of that interpretation by Dohmen, a student of Engel, in his 1905 dissertation. The now-obscure notion of connexes and its relation to Lie’s line elements and surface elements are discussed here in some detail. (shrink)

Carole Pearce's argument against African philosophy is founded on a set of factual flaws and the fallacious assumption that African philosophy is equivalent to ethnophilosophy, which she defines as a form of intellectual apartheid founded on irrational belief systems. I argue that African philosophy is in no way qualitatively different from, say, French or Chinese philosophy, and that ethnophilosophy is merely one aspect of it But ethnophilosophy could play the important role of critically evaluating African ethnic belief systems and the (...) interpretation of such by Western anthropologists. In general, African philoso phy is nothing more than the philosophical research (of whatever order) carried out by African philosophers in the context of African research paradigms. (shrink)

L. D. Harris; IV*—Solving the “Naval Battle”, Proceedings of the Aristotelian Society, Volume 78, Issue 1, 1 June 1978, Pages 45–62, https://doi.org/10.1093/ari.

L. D. Harris; IV*—Solving the “Naval Battle”, Proceedings of the Aristotelian Society, Volume 78, Issue 1, 1 June 1978, Pages 45–62, https://doi.org/10.1093/ari.

Provability logics with many modal operators for progressions of theories obtained by iterating their consistency statements are introduced. The corresponding arithmetical completeness theorem is proved.

A general equation is derived describing the concentration of all possible complexes of a central molecule with a set of ligands bound to the central molecule. This deduction allows the reaction rate constants for the binding of a given molecule to the central molecule to depend on the species of molecules already bound and the location of the molecules already bound. The model thus allows for structural alteration of the central molecule by binding. Functions describing the concentration dependence of any (...) effect whatever depending on the distribution of complexes are deduced. Possible applications and methods of application are indicated.II est dérivé une équation qui décrit la concentration des toutes les complexes d'une molécule centrale avec une collection de ligands connectés à la molécule centrale. La déduction montre comme les coefficients de la rapidité de reaction entre la molécule centrale et les molécules de la collection dépend de l'espèce et de la location des molécules déjà connectées.La modèle dérivée de l'équation montre les changements structurelles par la connection. Les functions qui décrivent la dependence de chaque effet à la concentration, sont dérivés. Ces effects dépendent aussi à la distribution des complexes. Des applications et des méthodes sont indiqués.Eine allgemeine Vergleichung hat man bekommen welche die Konzentration aller möglichen Komplexen eines zentralen Moleküles mit einer Reihe von „Ligands” verbunden mit dem zentralen Molekül beschreibt. Diese Folgerung gestattet dass die Reaktiongeschwindigkeit Konstanten für die Bindung eines gegebenen Moleküles mit dem zentralen Molekül abhÄngt von den Arten schon gegebenen Molekülen und die Ortsbestimmung der schon gebundenen Molekülen. Das Model zeigt die strukturelle Änderungen des zentralen Moleküls durch Bindung. Funktionen, die die Konzentrationband jedes Effektes beschreiben dass abhÄngt von der Distribution der Komplexen, sind abgeleitet.Mögliche Anwendungen und Methoden von Anwendung sind dargelegt. (shrink)

Clocks and Rulers Play Tricks. 6. Work Changes Mass. 7. Summing Up. Index. Unabridged republication of the edition published by Basic Books, Inc.

1. 4. 9. Fugite delicias, fugite enervantem felicitatem, qua animi permadescunt et, nisi aliquid intervenit quod humanae sortis admoneat, †velut perpetua ebrietate sopitif†. Although it is possible to produce a tolerable sentence by deleting et after permadescunt, it is generally agreed that a verb is missing in the last clause. Koch suggested sopiti, Gertz sopiti (...) manent Hermes, vivunt Schultess, languent Viansino. One would hesitate to add to the growing clutter of suggestions, did not one of Seneca's favourite verbs seem to meet all requirements, namely marcent. Cf. ben. 4. 6. 3 ‘quies in qua putrescis ac marces’; 4. 13. 1 ‘vobis voluptas est… securitatem sopitis simillimam adpetere e t … animi marcentis oblectare torporem’; dial. 1. 3. 10 ‘hunc voluptatibus marcidumet felicitate nimia laborantem’; 9. 2. 6; 10. 2. 2; epist. 74. 1; 89. 18 et al. (shrink)

The manuscript tradition of Seneca's Dialogues consists of one eleventhcentury manuscript, Ambrosianus C 90 inf. , which is the main source for the text, and a ruck of later manuscripts of lesser and disputed worth. There are over a hundred of these, far more than has been supposed.

The manuscript tradition of Seneca'sDialoguesconsists of one eleventhcentury manuscript, Ambrosianus C 90 inf., which is the main source for the text, and a ruck of later manuscripts of lesser and disputed worth. There are over a hundred of these, far more than has been supposed.

Upshot: Conversational conferences are difficult to design in a way that avoids the consequences that arise when participants are not experienced with or fully value the conversational mode of interaction. So, the designers of such conferences must experiment with ways to build a culture, use a structure, and facilitate participation that might mitigate some of these consequences. The potential of the experimental conference designed in the light of second-order cybernetics lies, in part, in the prospect of identifying and acquiring the (...) conversational abilities and appreciations necessary to support a participative-dialogic society. (shrink)

Purpose: This paper intends to connect ideas from the radical constructivist approach to cognition and learning to ideas from the constraint-theoretic approach to social policy formulation. It then extends these ideas to a dialogic approach to social transformation and design. Method: After demonstrating a correspondence between von Glasersfeld's fit/match distinction and my constraint-oriented/goal-oriented distinction with respect to policy formulation, the paper evaluates the basic assumptions of radical constructivism and builds from them a framework for thinking and talking about a desirable (...) society and ways to participate in its realization. Findings: The ideas of von Glasersfeld's radical constructivism contribute significantly to the development of a conceptual base for applied research on social activism by raising new questions and stimulating new thinking. Practical implications: Social activism in everyday affairs can be a way of living in the "world." Conclusion: The work and thought of Ernst von Glasersfeld opens a path toward a rich array of concepts and ideas with the potential to inform efforts in a wide variety of human endeavors. (shrink)