The problem of Common Knowledge will be considered in two classes of models: a class K.* of Kripke models and a class S of Scott models. Two modal logic systems will be defined. Those systems, KC and MC, include an axiomatisation of Common Knowledge. We prove determination of each system by the corresponding class of models. MSC: 03B45, 68T25.

We revisit the foundations of positive model theory, introducing h-inductive sentences. These allow a considerably simplified presentation of positive model theory, as well as a characterisation of Hausdorff cats by an amalgamation property of their h-inductive theory.

English Summary: This book focuses on how the Parmenides, one of the most mysterious Platonic dialogues, and more particularly the first hypothesis of the second part of the dialogue, was received and understood by the ancient writers claiming Plato. French Description: Ce livre se concentre sur la facon dont le Parmenide, un des dialogues platoniciens les plus mysterieux, et plus particulierement la premiere hypothese de la deuxieme partie du dialogue, a ete recu et compris par les auteurs antiques se reclamant (...) de Platon. Ce parcours historique a propos de la reception du Parmenide permet de mettre en evidence les presupposes exegetiques, parfois implicites, qui ont conduit a voir dans ce dialogue, tantot un exercice ou un traite logique, tantot une exposition d'une realite ontologique fondamentale, tantot la mise en evidence d'un principe transcendant et d'une theologie paienne systematique. L'etude des lectures antiques de la premiere hypothese du Parmenide presente en effet un triple interet, essentiel dans l'histoire de la philosophie occidentale, et que cet ouvrage analyse en detail : Un interet hermeneutique : l'etude ici presentee eclaire l'impense des lectures modernes de ce texte majeur. Un interet historique : l'auteur montre comment le Parmenide, loin d'etre un dialogue parmi d'autres, est le lieu ou s'est invente le neoplatonisme comme phenomene unitaire, construit autour de l'existence d'un principe radicalement transcendant, source de toute realite. Un interet proprement philosophique : le principe est a la fois en relation avec ce dont il est le principe, et transcendant a l'univers qu'il rend possible ; comment reconcilier sans contradiction transcendance et causalite, et parler de ce qui excede tout discours? L'etude examine precisement la maniere dont les neoplatoniciens, par une theorie originale de la negation, ont tente de trouver une reponse a ces difficultes. Dans cette histoire antique du Parmenide, les coups de force hermeneutiques traduisent de nouvelles configurations de pensee ; meme si l'enigme du texte leur resiste, leur etude permet de dresser une histoire originale des platonismes antiques. (shrink)

The studies gathered in this book attempt to fill a gap in the history of logic by stressing the importance of the works devoted to the question of logic in the tradition of thought inherited from...

In this article, I underline the profound link existing between Ricœur’s practical philosophy and language. Indeed, the latter bestows unity upon the former, because it constitutes its main axis, for methodological reasons. First of all, I recall Ricœur’s definition of discourse and explain its various transphrastic dimensions. I then show how this philosophy of language is carefully used to build a very coherent logic of judgment, which underlies all Ricœur’s epistemological reflections about normative disciplines. I particularly insist on the logic (...) of legal judgment. (shrink)

In this article, I wish to discuss in an informal way the motivations and the motifs of the constructivist approach to logic and mathematics and by a natural extension to the general field of science, particularly theoretical physics. Foundational questions in those domains are not ruled by philosophical principles, but a critical philosophy of foundations could be the leitmotiv to the extent that it can be used as a criterion to decide between the theoretical options of scientific practices that are (...) often oblivious to their own doctrinal presuppositions. My objective is to provide the justificatory reasons for a constructivist option or posture in the field of scientific knowledge. (shrink)