La logique cartésienne est introuvable parce qu’on a cherché une logique qui n’existe pas, c’est-à-dire une logique classique sur le modèle des manuels de la tradition réformée. La puissance transgressive de Descartes, même dans ce domaine, a été radicale : il a bafoué l’Arbre de Porphyre, vidé de sens la théorie des catégories, montré l’inutilité du syllogisme pour la recherche scientifique. Sans efficacité, à son avis, fut le renouveau d’une logique fondée sur des normes préconstituées. Il se « limite » (...) pourtant à suggérer, sur le modèle des procédés mathématiques, une attitude de pensée centrée sur l’intuitus et dont les relations sont garanties par les notions de « série » et de respectus. La transgression cartésienne a été si bouleversante que « Descartes logicien » devient un auteur maudit et l’attitude qu’il aurait voulu inspirer n’a connu aucune fortune, à telle enseigne que même la Logique de Port-Royal qu’on voudrait cartésienne consacre un grand espace à la syllogistique.Undiscoverable is the Cartesian logic, because scholars looked for a logic that does not exist, i.e. a classical logic after the model of traditional, more or less reformed, manuals. Descartes’ transgressive power was radical even in this domain : he scorned Phorphyrius Tree, voided the theory of categories of all meaning, showed the uselessness of syllogism for scientific research. Just as totally ineffective was, in his view, the renewal of a logic founded on preconstituted norms. He therefore « limits » himself to suggest, after the model of mathematical procedures, an attitude of thought centered on intuitus and whose relationships are guaranteed by the notions of « series » and respectus. The Cartesian transgression turned out to be so upsetting that « Descartes the logician » became a wicked author and the attitude he had meant to inspire had no fortune whatsoever, to such a point that even the Logic of Port-Royal – purportedly Cartesian – leaves much room to syllogistics. (shrink)

This paper gives two complete and elementary proofs that if the speed of light over closed paths has a universal value c, then it is possible to synchronize clocks in such a way that the one-way speed of light is c. The first proof is an elementary version of a recent proof. The second provides high precision experimental evidence that it is possible to synchronize clocks in such a way that the one-way speed of light has a universal value. We (...) also discuss an old incomplete proof by Weyl which is important from an historical perspective. (shrink)

The mental representation of one’s own body does not necessarily correspond to the physical body. For instance, a dissociation between perceived and actual reach-ability has been shown, that is, individuals perceive that they can reach objects that are out of grasp. We presented participants with 3D pictures of objects located at four different distances, namely near-reaching space, actual-reaching space, perceived-reaching space and non-reaching space. Immediately after they were presented with function, manipulation, observation or pointing verbs and were required to judge (...) if the verb was compatible with the object.Participants were faster with function and manipulation verbs than with observation and pointing verbs. Strikingly, with both function and manipulation verbs participants were faster when objects were presented in actual than the perceived reaching space. These findings suggest that our knowledge of the world is implicitly built online through behaviour, and is not necessarily reflected in explicit estimates or conscious representations. (shrink)

The paper examines the all too often neglected role of the Czech philosopher and mathematician Bernard Bolzano for Husserl’s work, from ca. 1893–1894 onwards. Husserl himself finds it important to stress in an appendix to chapter 10 of the Prolegomena to Pure Logic that his investigations are not “in any sense mere commentaries upon, or critically improved expositions of, Bolzano’s thought patterns”, but that they “have been crucially stimulated by Bolzano …”. The paper examines early Bolzano’s ideas on the ground-consequence (...) relation, Bolzano’s logical universe as presented in his masterpiece, the monumental Wissenschaftslehre, the role of Hermann Lotze in making Husserl receptive for Bolzano and, finally, a lecture course on logic held by Husserl at the University of Halle in 1896, working out just what Husserl is taking, and not taking, from Bolzano. (shrink)

Per uscire dalle aporie delle proprie conseguenze, la scienza deve vedere riconosciuto l'atto come uno dei propri principi fondamentali (accanto all'ente e alla parola). Scienza è, infatti, mettere in relazione le cose (la "natura") con delle leggi matematiche (vale a dire con dei simboli e dei concetti). Ma mettere in relazione è un atto. Sicché, la scienza si fonda su tre principi (ente, parola, atto) e sui corrispettivi campi filosofici (ontologia, logica, etica). Tenere conto di quest'ambito triadico serve a mostrare (...) che l'epistemologia non è un sapere neutro e descrittivo, ma è un prendere partito: al tempo stesso dal punto di vista etico, politico, morale e giuridico. (shrink)

Logic was understood by the Stoics in a broad sense, as the doctrine that included analysis of the forms of argumentation, rhetoric, theory of concepts and propositions, epistemology, and philosophy of language. The distinguishing characteristic of Stoic logic is the fact that it is fundamentally a logic of propositions, unlike the logic of terms belonging to the Aristotelian tradition. This study offers a new treatment of Stoic logic, in which the various topics are retraced and critically assessed.

The strongly innovative theory of whole-parts relations outlined by Husserl in his Third logical Investigation—to which he attributed a basic value for his entire phenomenology—has recently attracted a renewed interest. Although many important issues have been clarified (especially by Kit Fine) the subject seems still worth being revisited. To this aim Husserlian universes are introduced. These are lower bounded distributive lattices endowed with a unary operation of defect and a binary relation of isogeneity. Husserl's contents are identified with nonzero elements (...) of a Husserlian universe and the dependence relations among contents are defined and studied starting from the idea that the defect of xis what x needs in order to ‘exist’ i.e., in order to be ‘closed’ with respect to the closure operation defined as the sup of x and its defect. It turns out that there are (at least) eight dependence relations which are worth to be considered. Many other questions concerning the world of contents (among them the proofs of the famous Husserl's Sätze) may now be discussed and clarified. Then the theory of species and genera is developed. Ultimate species (for short: species) are identified with equivalence classes of contents modulo isogeneity, and species in general (for short: genera) are identified with arbitrary unions of species. On the basis of the relation obtaining among two contents when they are isogeneous to two contents the first of which is a part of the second it becomes possible to develop a rather satisfying interpretation of Husserl's theory of the dependencies among species and genera and of the material a priori laws. By strengthening the notion of Husserlian universe into the notion of rigid Husserlian universe, the theory of species and genera obtains a stronger version. Three models of the theory are exhibited. The first one, suggested by combinatorial-topological considerations, identifies contents with finite non-empty sets of natural numbers; the second one identifies contents with non-empty sets of formulas of a formal language; the third one (not totally ‘rigid’) identifies contents with positive integers. (shrink)

This paper gives two complete and elementary proofs that if the speed of light over closed paths has a universal value c, then it is possible to synchronize clocks in such a way that the one-way speed of light is c. The first proof is an elementary version of a recent proof. The second provides high precision experimental evidence that it is possible to synchronize clocks in such a way that the one-way speed of light has a universal value. We (...) also discuss an old incomplete proof by Weyl which is important from an historical perspective. (shrink)

By analysing the policies and ideas of German social democracy, the British Labour Party and the Italian Communist Party, this article explores their attitude towards science and their imagination of the future in the 1950s. Deeply different, social democrats and communists shared a positivist attitude in favour of scientific progress and high modernity. This painted their attitude towards the space race, peaceful nuclear power and automation. Science was conceived as a neutral power to be supported, but it required political guidance (...) to harness it and turned it into social progress. Thus, their disagreement was over the political implications for capitalist societies experiencing growing prosperity. Science was also a powerful rhetorical argument to castigate the conservatives for failing the nation and allowing it to decline and fall behind its competitors. The article combines comparison and transnational history, innovating the latter by introducing the concepts of horizontal, vertical and antagonistic transnationalism. (shrink)

This book is focused on the first three parts of Bolzano's Theory of Science and introduces a more systematic reconsideration of Bolzano's logical thought. In undertaking this task, the book is intended as an exploration, not so much of the more specifically discursive aspects of Bolzano's logical thought - already amply studied - as much as on identifying the singularly coherent and systematic nature of the logic presented in Bolzano's work.