L’analyse des réseaux sociaux est menée dans le domaine des sciences sociales depuis les années 1930. Le premier enjeu pour réaliser ces analyses se situe dans la collecte de l’information sur la structure de ces réseaux et sur leurs activités. Avec l’avènement du Web 2.0 et des technologies du Web sémantique, plusieurs mécanismes de collecte d’information sont désormais envisageables. Cependant, très peu d’utilisateurs sont conscients des facilités d’atteinte et de manipulation de leurs traces d’activités et de leurs données personnelles de (...) plus en plus rendus publics sur les réseaux socionumériques en particulier. Dans cet article, nous étudions les différentes approches permettant l’accès aux données dans les réseaux socionumériques, en nous intéressant − dans le cas précis de Facebook − à la qualité et la quantité de l’information accessible, et par conséquent, aux risques potentiels d’atteinte et de manipulation des données personnelles des utilisateurs par des tiers. Une expérimentation menée via l’API Facebook démontre l’accessibilité à un nombre important d’informations pouvant permettre de reconstruire automatiquement le réseau réel d’un utilisateur à partir de son profil.Social networks have been an object of analysis by the social sciences since the 1930s. The first challenge in performing these analyses is to gather information on the structure of these networks and on their activities. With the advent of Web 2.0 and semantic Web technologies, several different mechanisms can be used for this. However, few users are aware of how easy it is to access and manipulate the traces left by their activities and, especially on the social networks, by their personal data, which is becoming increasingly public. In this article, we look into the different ways of accessing data on the social networks, and – on Facebook in particular – into the quality and quantity of the information available and therefore the potential risks of users finding that third parties are accessing and manipulating their personal information. An experiment conducted via API Facebook shows that a great deal of information is accessible that can be used to automatically reconstruct a user’s actual network from their profile. (shrink)

Pourquoi l'humanité dans son ensemble ne s'améliore-t-elle pas? Pourquoi le progrès moral ne suit-il pas le progrès scientifique et technique? Les prisonsŠseront-elles fermées un jour? Toutes ces questions font écho de la réalité du mal dans sa force, dans son cycle interminable : un mal appelle un autre mal. Si nous avons la conscience du mal moral – du mal relatif au bien ou contraire à un bien défini – la conscience du mal, en dehors de toute définition de bien, (...) manquerait cruellement à l'humanité. La culture de tenir le mal dans sa positivité pourra rendre possible la libération éthique de la force du mal. (shrink)

La 4e de couverture indique : "La philosophie de Teilhard a apporté de nouveaux arguments de justification pour l'éthique des droits fondamentaux, laquelle se fonde traditionnellement sur le caractère rationnel de l'homme. En effet, Teilhard établit que cette rationalité découle d'une admirable évolution biologique, qui a pu sortir l'homme de l'animalité pour l'inscrire dans l'humanité. Ainsi, l'éthique en question se justifie concrètement par le fait que l'homme incarne la figure la plus aboutie de l'évolution, qui s'est spiritualisée, faisant de l'être (...) humain la portion la plus précieuse du cosmos. Autrement dit, notre caractère rationnel, pivot de la justification classique des droits fondamentaux, émane tout d'abord d'une anthropogenèse biologique. En déroulant cette perspective, l'auteur du présent essai a mis en évidence et développé ce qu'il nomme argumentaire évolutionniste des droits de l'homme. Cet argumentaire éclaire par ailleurs la légitimité de la bioéthique et de l'écologie, tout en plaidant pour l'humanisation de la globalisation et de la gourvernance mondiale.". (shrink)

RésuméLa qualité essentielle d'un mathématicien est l'imagination; la logique ne sert qu'à mettre les démonstrations sous une forme irréfutable, elle est incapable de les suggérer. L'imagination se fonde sur une sorte d'« intuition » des objets mathématiques étudiés, mais cela n'a que très peu de contact avec ce qu'on appelle d'ordinaire l'« intuition » sensible, les objets mathématiques considérés étant le plus souvent l'aboutissement d'un long processus d'abstraction qui leur ǒte toute possibilité de représentation concrète. Cette « intuition » mathématique (...) est avant tout le résultat d'une longue familiarité avec le sujet étudié; mais en outre il peut s'opérer des « transferts » d'intuition d'une théorie dans une autre; on en donne quelques exemples qui font ressortir la fécondité de tels transferts. (shrink)

Born in 1799 in Moscow, Alexander Sergeyevich Pushkin - who has been called the “founder of poetic and literary language in Russian” (Belinski, Turgenev), “the first of the Russians” (Dos-toyevski), “the first Russian artist-poet” (Belinski), “the original model for Russian identity” (Grigoriev), “an extremely rare and perhaps unique phenomenon of the Russian spirit” (Gogol), “the sun of the Russian intellectual conception of the world” (Dostoyevsky) - could trace his roots back to African ancestors. His mother, Nadine Hanibal, was the granddaughter (...) of “The Negro of Peter the Great,” Abraham Petrovich Hanibal, who at the beginning of the eighteenth century fell victim to the black slave trade with the Ottoman Empire. (shrink)

Climate change harmfully affects social and natural systems. These outcomes adversely affect the human and natural systems, resulting in adopting related-response measures whose implementation yields similar outcomes, especially when poorly designed. Climate-related projects, actions, and policies cause harmful environmental impacts, even though the United Nations Convention on Climate Change and its subsequent instruments urge parties, when dealing with climate change, to employ methods that preserve the quality of the environment. Few studies have established the effects of these environmentally, economically, culturally, (...) and socially unsound mechanisms on public participation, although research usually proves that ecological and environmental citizenship can enhance climate action. The study also highlights gaps in the common understanding of public participation in climate action. This reflection analyses the relationships between public participation and climate response measures and concludes that uncertainty related to response measures could affect the perception of climate action by the public. The reflection, therefore, shows that many international environmental law legal instruments, policies, and scholarships attempt to address the issue. (shrink)

Jean Dieudonné, the spokesman of the group of French mathematicians named Bourbaki, called mathematics the music of reason. This metaphor invites a phenomenological account of the affective, in contrast to the epistemic and discursive, nature of mathematics: What constitutes its charm? Mathematical reasoning is described as a perceptual experience, which in Husserl’s late philosophy would be a case of passive synthesis. Like a melody, a mathematical proof is manifest in an affective identity of a temporal object. Rather than an exercise (...) for its own sake, this account sheds a different light on both the epistemic limitation of mathematical science, and the discursive problem of social responsibility in mathematics – two issues at the heart of Husserl’s critique of science as well as of mid-20th century mathematics, for which Nicolas Bourbaki stands as a monument of rigor. (shrink)

No mathematician did more to change mathematics in the second half of the twentieth century than Alexandre Grothendieck. This would have been true even if he had been a quiet figure with a liking for playing the piano and walking in the hills but, as this book makes very clear, he was far from that, and his character and his way of working enhanced his impact. Above all, there was his abrupt departure from the world of mathematics in 1970 and (...) his occasional interventions in it since.This review was submitted a few days before Grothendieck's death in November 2014—Editor.As a teenager, Grothendieck had lived with his mother protected from the Nazis by courageous Huguenots in the village of Le Chambon-sur-Lignon. Immediately after the war, he went to the University of Montpellier where he studied mathematics and soon made his way to Nancy and was introduced to Dieudonné and Schwartz, who were members of Bourbaki. His first original work was in the theory of Banach spaces where, in the wo .. (shrink)

Alexandre Grothendieck foi um dos maiores matemáticos do século 20 e um dos mais atípicos. Nascido na Alemanha a um pai anarquista de origem russa, sua infância foi marcada pela militância política dos seus pais, assim passando por revoluções, guerras e sobrevivência. Descoberto por sua precocidade matemática por Henri Cartan, Grothendieck fez seu doutorado sob orientação de Laurent Schwartz e Jean Dieudonné. As principais contribuições dele são na área da topologia e na geometria algébrica, assim como na teoria das categorias. (...) No final dos anos de 1960, ele se dedicou à militância política e ecológica, organizando a revista Survivre durante três anos. Em 1986, publicou um manuscrito autobiográfico de 1000 páginas, Récoltes et semailles, em que ele descreve sua experiência e sua prática da matemática, assim suas contribuições à comunidade matemática francesa. Pouco comentado na filosofia, as implicações dos seus descobrimentos fora mais recentemente discutidas por Alain Badiou na sua "fenômeno-lógica", em Logiques des mondes e Arkady Plonitsky, Mathgematics, Science and postclassical Theory, pesquisa trata da semelhança entre os aspectos formais da filosofia de Gilles Deleuze e da topologia de Grothendieck. (shrink)

Reviewed by F. PATRAS, Laboratoire J.-A. Dieudonné, Université Côte d'Azur and CNRS, Nice, France. [email protected] those who are interested in Husserl’s philosophy of mathematics and its links w...

In his 1622 work The Assayer, Galileo commented on the necessity of mathematics for understanding the natural world. "Philosophy is written in this very great book. . . . It is written in mathematical language and the characters are triangles, circles and other geometrical figures." More than 300 years later, debating math education at the 1958 International Congress of Mathematicians, French mathematician Jean Dieudonné interjected: "Down with Euclid! Death to triangles!".

There are two possible strategies for investigating questions on logic and mathematics. First, one can adopt the pattern recommended by the phenomenologists, which consists in looking for the actual essences of logic and mathematics in order to relate both fields. The second approach, adopted in this paper, starts with a historical review of the foundational standpoints. I will then try to extract on this base some insights on how logic and mathematics are mutually related. In particular, I am interested in (...) the concept of logic suggested by the development of the foundational debate. Yet one more preliminary remark is here in order. I will take into account the classical foundational positions: logicism, intuitionism, and formalism, as well as their later modifications and changes.1 Of course, this, so to speak, Foundational Trinity, does not exhaust the complete map of the foundations and philosophy of mathematics. For instance, I entirely neglect views wich might be exemplified by Lakatos, Dieudonné or Hersh, who, roughly speaking, radically deny that the study of logic and its relation to mathematics provides any interesting problem. I do not feel competent myself to judge this matter from the point of view of working mathematicians. On the other hand, philosophers are traditionally interested in the nature of logic and its links with other fields. Consequently, I regard my problem rather as a way of understanding what logic is, than whether it is important for mathematics or not. (shrink)

Topology uses simple geometric and algebraic ideas, but its huge success and vast ramifications make it a tough nut for historians of twentieth‐century mathematics. Two books have addressed it well: Dieudonné chronicles about one thousand key definitions and theorems, and essays in James focus on forty central themes. Both assume considerable mathematics, but neither offers a historical synthesis of the simplest core ideas. Now, Alain Herreman uses semiotics to watch these leading ideas develop through the founding works of Henri Poincaré, (...) Oswald Veblen, James Alexander, and Solomon Lefschetz. Herreman states outright that semiotics will not exhaust these meanings, but he makes it a revealing tool.The method is especially suited to Poincaré, who will define one technical term repeatedly in a single work, each time differently, as if it was the first, and perhaps no definition will match any use of the term in proofs. For Poincaré no term gets meaning from a definition. Each functions in relation to the others—that is, specifically in relation to other terms in Poincaré's work. It is no use invoking standards of rigor current in Poincaré's time and place or then‐current definitions. Poincaré was well known at the time for using neither: Poincaré's meanings must be derived from his writing, as Herreman does.Herreman bases his semiotics on Hjelmslev yet refutes Hjelmslev's concern that mathematics may be “monoplanar,” with no content beyond the signs themselves . The book depicts four levels of content at work in these authors: algebraic, geometric, arithmetic, and set theoretic. Herreman says a sign has algebraic content if its use depends on its written expression, the way polynomials are formal expressions added and multiplied by formal rules. Early topologists—here especially Alexander—sought purely combinatorial methods. Thus a “cube” is a set of six “faces,” twelve “edges,” and eight “vertices,” each taken as primitive and described only by a short table showing which ones meet which. Combinatorics typifies arithmetic content for Herreman. Yet a cube is also an infinite set of points. Herreman speaks of geometric content when a sign indicates both a set of parts and a set of points. Today we might use different notations for the set of points and the set of parts—Poincaré et al. did not. Herreman will not reconstruct their works or restate them in other words; rather, he uses these levels of content to organize extensive quotations and analyze the relations in each text as they move toward deeper union of the algebraic and geometric.The chapter on Lefschetz makes a great finale. Lefschetz is arguably Poincaré's closest and greatest student, though the two never met. Like Poincaré's, his work is at once compelling and baffling, decisive for the future of mathematics yet brutally difficult to absorb. Semiotics serves well in presenting this mathematician who “never stated a false theorem or gave a correct proof,” as his friends joked.The book does not go far into theorems. Yet it requires some background. A beginner might enjoy it with Alexandroff , a gem itself, written with unusually strong historic sense. Specialists will enjoy reading it with the original works for its fresh viewpoints and novel connections. It is a fine way to analyze the works, to see how they create their own meanings. (shrink)

Reviewed by F. PATRAS, Laboratoire J.-A. Dieudonné, Université Côte d'Azur and CNRS, Nice, France. [email protected] those who are interested in Husserl’s philosophy of mathematics and its links w...