Papers... "selected from a larger number of contributions most of them based on talks presented at the First World Congress on the Square of Opposition organized in Montreux in June 2007"--Preface, p. 12.

This text is an outgrowth of notes prepared by J. Y. Girard for a course at the University of Paris VII. It deals with the mathematical background of the application to computer science of aspects of logic (namely the correspondence between proposition & types). Combined with the conceptual perspectives of Girard's ideas, this sheds light on both the traditional logic material & its prospective applications to computer science. The book covers a very active & exciting research area, & it will (...) be essential reading for all those working in logic & computer science. (shrink)

Ludics [1] is a novel approach to logic—especially proof-theory. The present introduction emphasises foundational issues.For ages, not a single disturbing idea in the area of “foundations”: the discussion is sort of ossified—as if everything had been said, as if all notions had taken their definite place, in a big cemetery of ideas. One can still refresh the flowers or regild the stone, e.g., prove technicalities, sometimes non-trivial; but the real debate is still: this paper begins with an autopsy, the autopsy (...) of the foundational project.Up to say 1900, the realist/dualist approach to science was dominant; during the last century some domains like physics evolved so as to become completely anti-realist; but this evolution hardly concerned logic.By the turn of the XXth century mathematics was jeopardised by paradoxes, the most famous of them being due to Russell. Hilbert's reaction was to focus on consistency. But the reduction of paradoxes—and therefore of foundations—to solely the antinomies is highly questionable: indeed, the typical paradoxical artifacts are secret sharers, objects satisfying the formal definitions but far astray from the intended meaning, typically the Peano “curve” which contradicts our perception of dimension. Fortunately, topology has been able to show that dimension m is not the same as dimension n … but just for a second, forget this and imagine consistent mathematics in which balls in any dimension are homeomorphic: what a disaster! This exclusive focus on consistency—not to speak of the strategic failure of the Programme—should explain why logic, especially foundations lost contact with other sciences during last century. (shrink)

A collection of papers from Paul Hertz to Dov Gabbay - through Tarski, Gödel, Kripke - giving a general perspective about logical systems. These papers discuss questions such as the relativity and nature of logic, present tools such as consequence operators and combinations of logics, prove theorems such as translations between logics, investigate the domain of validity and application of fundamental results such as compactness and completeness. Each of these papers is presented by a specialist explaining its context, import and (...) influence. (shrink)

In this paper we discuss the notion of “possible worlds” contrasting a philosophical idea due to Malebranche with a mathematical concept of modern logic due to Kripke from which many pseudo-philosophical discussions have arisen.

"Christian philosophy" is commonly regarded as an oxymoron, philosophy being thought incompatible with the assumptions and conclusions required by religious faith. According to this way of thinking, philosophy and theology must forever remain distinct. In From Theology to Theological Thinking, Jean-Yves Lacoste takes a different approach. Stepping back from contemporary philosophical concerns, Lacoste--a leading figure in the philosophy of religion--looks at the relationship between philosophy and theology from the standpoint of the history of ideas. He notes in particular (...) that theology and philosophy were not considered separate realms until the high Middle Ages, this distinction being a hallmark of the modern era that is coming to an end. Lacoste argues that the intellectual task before us now is to work in the frontier region between or beyond these domains, work he identifies as "the task of thinking." With this argument, Lacoste resets our understanding of Western Christian thought, contending that a new way of thinking that is at once philosophical and theological will be the lasting discourse of Christianity. (shrink)

This paper introduces the special issue on Logic and Religion of the journal Logica Universalis (Springer). The issue contains the following articles: Logic and Religion, by Jean-Yves Beziau and Ricardo Silvestre; Thinking Negation in Early Hinduism and Classical Indian Philosophy, by Purushottama Bilimoria; Karma Theory, Determinism, Fatalism and Freedom of Will, by Ricardo Sousa Silvestre; From Logic in Islam to Islamic Logic, by Musa Akrami; Leibniz’s Ontological Proof of the Existence of God and the Problem of Impossible Objects, (...) by Wolfgang Lenzen; A Logical Analysis of the Anselm’s Unum Argumentum (from Proslogion), by Jean-Pierre Desclés; Monotonic and Non-monotonic Embeddings of Anselm’s Proof, by Jacob Archambault; Computer-Assisted Analysis of the Anderson–Hájek Ontological Controversy, by C. Benzmüller, L. Weber and B. Woltzenlogel Paleo. (shrink)

Jean-Jacques Rousseau est l'auteur de l'entrée "économie politique" dans l'Encyclopédie en 1755. A ce titre, il aurait pu être l'un des fondateurs de cette discipline. Pourtant, la définition qu'il en donne est à l'encontre de la pensée libérale des physiocrates, puis des classiques, et constitue une véritable "anti-économique". En hypertrophiant le rôle de l'Etat et en niant l'intérêt personnel, Rousseau est au contraire l'un des pères du socialsme. En niant la liberté humaine, il nie aussi l'existence de choix éthiques.

Jean-Yves Strasser The Olympia of Alexandria and the Pancratiast M. Aur. Asklepiades p.421-468 The Alexandrian Olympia are known thanks to inscriptions and especially papyri. The latter mention the olympionikoi, who may have been victors not in the great competition at Pisa, but in the Olympia of the Egyptian city. These competitions, created under Marcus Aurelius, became eiselastikoi under Gallien; they were first celebrated in 268. Like the majority of the great competitions in Egypt, they took place in the (...) winter of even years divisible by four. That was the case already in the 2nd century AD: the first Olympia were organised in 180. In 200, at the time of the sixth celebration, the periodonikes M. Aur. Asklepiades won the Olympia pancration in the presence of Septimius Severus and Caracalla. An inscription at Coptus (I. Portes 88) mentions a hellanodikes of Alexandria: he could have been serving at the time of the seventeenth Olympiad in 244; in 246-247 he had a statue of Sarapis Polieus erected under the prefect of Egypt Valerius Firmus. (shrink)

We assess the celebration of the 1st World Logic Day which recently took place all over the world. We then answer the question Why a World Logic Day? in two steps. First we explain why promoting logic, emphasizing its fundamental importance and its relations with many other fields. Secondly we examine the sense of a one-day celebration: how this can help reinforcing logic day-to-day and why logic deserves it. We make a comparison with other existing one-day celebrations. We end by (...) presenting and commenting the logo of the World Logic Day. (shrink)

We discuss the history of the revival of the theory of opposition, with its emerging paradigms of research, and the related events that are organized in this perspective, including the latest one in Leuven in 2022.

For several years I have been developing a general theory of logics that I have called Universal Logic. In this article I will try to describe how I was led to this theory and how I have progressively conceived it, starting my researches about ten years ago in Paris in paraconsistent logic and the broadening my horizons, pursuing my researches in Brazil, Poland and the USA.

After recalling the distinction between logic as reasoning and logic as theory of reasoning, we first examine the question of relativity of logic arguing that the theory of reasoning as any other science is relative. In a second part we discuss the emergence of universal logic as a general theory of logical systems, making comparison with universal algebra and the project of mathesis universalis. In a third part we critically present three lines of research connected to universal logic: logical pluralism, (...) non-classical logics and cognitive science. (shrink)

L'expérience de la connaissance nous enseigne qu'il n'y a pas de Réalité Dernière, que tout train en cache un autre. Une évidence qu'il n'est pas facile d'accepter, d'où l'idée de ce train ultime, celui qui ne cacherait plus rien. La transparentisme postule l'existence, au-delà de la perception immédiate, d'un monde, d'un niveau de lecture, complètement intelligible, i.e, explicite et immédiat. D'où cette croyance en de prétendus "rayons X du savoir" qui nous dévoileraient l'envers de l'Univers.

The first volume presents a collection of papers in honor of the fiftieth birthday of Jean-Yves Béziau. These 25 papers have been written by internationally distinguished logicians, mathematicians, computer scientists, linguists and philosophers, including Arnon Avron, John Corcoran, Wilfrid Hodges, Laurence Horn, Lloyd Humbertsone, Dale Jacquette, David Makinson, Stephen Read, and Jan Woleński. It is a state-of-the-art source of cutting-edge studies in the new interdisciplinary field of universal logic. The papers touch upon a wide range of topics including (...) combination of logic, non-classical logic, square and other geometrical figures of opposition, categorical logic, set theory, foundation of logic, philosophy and history of logic (Aristotle, Avicenna, Buridan, Schröder, MacColl). This book offers new perspectives and challenges in the study of logic and will be of interest to all students and researchers interested the nature and future of logic. (shrink)

We discuss Sengupta's argumentation according to which Frege was wrong identifying reference with truth-value.After stating various possible interpretations of Frege's principle of substitution, we show that there is no coherent interpretation under which Sengupta's argumentation is valid.Finally we try to show how Frege's distinction can work in the context of modern mathematics and how modern logic grasps it.

Les philosophies de l'histoire se nourrissaient de miettes tombées de la table du théologien. L'effondrement de leurs projets onto-théologiques permettrait-il de penser enfin l'histoire en fidélité au logos de la philosophie? Mettre toute métaphysique de l'histoire entre parenthèses ne consacre pas l'éternel retour du même, ou plutôt du pareil, mais libère le champ d'une temporalité plénière. Et parce que la temporalité - le temps tel que je le vis et que nous le vivons - se déploie comme ce que l'on (...) peut nommer une histoire, celle que je suis et celle que nous sommes, alors la question philosophique de l'histoire peut être logée sans reste dans une quaestio de tempore formulée après Husserl et Heidegger, et certains autres : sans préjuger d'une eschatologie que seule la théologie peut organiser, mais en s'autorisant à en précomprendre les raisons. L'existence est le mode d'être de l'étant que nous sommes, et l'existence est être en/comme histoire, historialité. L'historialité est une dimension de la temporalité. Qui le sait saura éviter les ornières de la philosophie de l'histoire. Non pas pour décrire une existence sans histoire, mais pour rendre raison du phénomène de l'histoire. En première instance seulement, certes, mais en rigueur, parce que sans prétention apocalyptique indue. L'histoire dont nous parlons est une réalité avant-dernière."--Page 4 of cover. (shrink)

Que la musique soit faite pour etre ecoutee semble une evidence, et pourtant... C'est pour guider les melomanes et les aider a passer d'une audition passive a une ecoute active que Jean-Yves Bras partage ici son experience d'ecouteur. Apres avoir defini ce qu'est la musique, il s'interroge ensuite sur la nature de l'ecoute: que faut-il entendre par ecouter? Sur quoi porter notre attention? Comment ecouter? Les conditions materielles dans lesquelles nous consommons la musique, notre comportement au concert ou (...) a l'ecoute d'un disque, ont egalement une incidence importante sur la qualite de notre ecoute. Puis il analyse ces liens si mysterieux et si essentiels tisses entre compositeurs, interpretes et nous-memes, auditeurs. Enfin, il trace a grands traits l'histoire de nos oreilles de l'Antiquite a nos jours, pour conclure sur les differentes categories d'auditeurs actuels. Parallelement, l'auteur a cree un site Internet, www.artdecouter.fr, qui apporte un complement d'information agremente d'exemples sonores. Ce chemin d'initiation se parcourt sous forme de dialogue: une jeune personne souhaitant s'instruire, Mademoiselle Croche, nous permet par ses questions d'entendre s'ouvrir pour nous le langage de la musique. Jean-Yves Bras a ete directeur de la Documentation musicale de Radio France et a participe a de nombreuses emissions. Responsable artistique du Festival Chopin a Paris, il est l'auteur des Courants musicaux du XXe siecle et d'un ouvrage sur le chef d'orchestre Carlo Maria Giulini. (shrink)

1 What are the features of a paraconsistent negation? Since paraconsistent logic was launched by da Costa in his seminal paper [4], one of the fundamental problems has been to determine what exactly are the theoretical or metatheoretical properties of classical negation that can have a unary operator not obeying the principle of noncontradiction, that is, a paraconsistent operator. What the result presented here shows is that some of these properties are not compatible with each other, so that in constructing (...) a paraconsistent negation as close as possible to classical negation, we have to make a choice among classical properties compatible with the idea of paraconsistency. In particular, there is no paraconsistent negation more classical than all the others. (shrink)

I discuss the origin and development of logic prizes around the world. In a first section I describe how I started this project by creating the Newton da Costa Logic Prize in Brazil in 2014. In a second section I explain how this idea was extended into the world through the manifesto A Logic Prize in Every Country! and how was organized the Logic Prizes Contest at the 6th UNILOG in Vichy in June 2018 with the participation of 9 logic (...) prizes winners from 9 countries. In a third section I discuss how this project will develop in the future with the creation of more logic prizes, an Encyclopædia of Logic, the book series Logic PhDs, as well as the creation of a World Logic Day, January 14, day of birth of Alfred Tarski and of death of Kurt Gödel. (shrink)

This paper discusses the development of the Logic and Religion project and the various events organized within this framework, particularly the 3rd and 4th editions, with this volume including papers presented at both.

In lieu of an abstract, here is a brief excerpt of the content:Reviewed by:Heidegger and Dao: Things, Nothingness, Freedom by Eric S. NelsonJean-Yves Heurtebise (bio)Heidegger and Dao: Things, Nothingness, Freedom. Eric S. Nelson. London: Bloomsbury, 2024. Pp. viii + 256. Paper $103.50, ISBN 978-1-350411-90-6.On the Way: from Heidegger to Nagarjuna via Lao-ZhuangAfter having reviewed Eric S. Nelson’s 2017 Chinese and Buddhist Philosophy in Early Twentieth-Century German Thought (for the Journal of Chinese Philosophy) and his 2020 Daoism and Environmental Philosophy (...) (for Monde Chinois Nouvelle Asie), reviewing now, for Philosophy East & West, Nelson’s 2024 Heidegger and Dao: Things, Nothingness, Freedom, which develops on the insights of his two previous opuses, is both a real pleasure and a true challenge. It’s a pleasure to read again Eric S. Nelson’s scholarly prose with its own specific conceptual style and distinctive philosophical rhythm. It’s a challenge to give a meaningful and fair overview of a conceptually complex, scholarly rich, and thought-provoking book.No one can speak better about the aim and goals of Nelson’s book than the author himself--following the wayist way of spontaneous ziranity, we will thus let the book speak for itself:Its primary thesis is that, entangled with Daoist and other intercultural sources, Heidegger’s path proceeds from the paradigmatic Occidental philosophy of available givenness and mere presence--which conceals the open spacing of things and seeks to logically exclude and dialectically subordinate negativity and the nothing--to nothingness, emptiness, and the clearing in their coming to presence and withdrawal in absence or, to accentuate its mutable verbal sense, presencing-absencing. […] Zhuangzi’s vision of free and easy wandering indicates ways of practicing philosophy as contesting and unraveling fixations. These practices allow rethinking Heidegger’s pathways and reimagining for ourselves things, nothingness, and world in the specificity of our existential condition.(p. 10)These lines can give already a good indication about what the reader will be provided with: a Heideggerian reading of Daoism nurturing and enriching a Daoist reading of Heidegger; a Daoist reinterpretation of the late Heidegger feeding and complexifying a Heideggerian Pre-Socratic reinterpretation of early Daoism; a continuous feedback loop leading to a process of mutual symbiosis and multiple conceptually creative hybridizations. Ziran and Dao are used to unlock the concealed potentialities of overdetermined Western concepts such as Nature and Ethos while the Heideggerian deconstruction of “Western metaphysics” is [End Page 1] used to de-Eurocentricize our understanding of Daoist and Buddhist thoughts about Thing and Nothingness.The book is divided in two parts: the first part deals with the concept of Thing, the second with the concept of Nothingness. Thing and Nothingness seem to be the perfect antithesis but the magic of Nelson’s reading of their tri-cultural Daoist, Buddhist and Heideggerian conceptualization is to dissipate the classical, ontological antinomy between Being and Non-Being to explore what’s both beyond and below: the natural source of life emergence, coming and returning to a Nothing that is Everything via a Thing that is never Anything (a ready-made and exchangeable object in the universal trading scheme of capitalist general equivalence) but always Something (this and that in particular, in their own specific rhythm of coming back and forth, from and to their source of un-nothingity).The first five chapters evoke the issue of the encounter of Heidegger and Daoist thinking in relation to the deconstruction of Thingness. In the first chapter, Nelson proposes a cross-cultural perspective about the Nature of the Thing linking Heidegger’s critique of the reduction of Things’ Presence to Functional Tools to the Daoist extended conception of Things in terms of Multitude (wanwu 萬物), in which objects, living beings, and spirits participate in the fabric of reality. Chapter 2 examines the connection between Heidegger’s and Daoism’s understanding of “nature” as manifesting a distinct yet similar attention to things’ autopoiesis: following the natural disclosing and unfolding of “things” entails a specific way to think and be in the world. In chapter 3, a comparison is established between Heidegger and Laozi with respect to the notion of void and emptiness: the fact that what powers the utility of a thing is what... (shrink)

In a first section, we discuss Quine’s claim according to which identity is a logical notion. We point out that Quine mixes up various types of identities: trivial (or diagonal) identity, Leibniz identity, etc.; and this leads him to commit several mistakes. In a second section, we review Quine’s criticisms to various philosophers (Wittgenstein, Whitehead, Leibniz, etc.), who ac-cording to him made confusion between names and objects in defining identity. We show that in fact only Korzybski can be accused of (...) such confusion. In a third section, we analyze the relation between identity and entity. We notice that for Quine a river is the result of the identification of river stages, but that he admits it as an entity by opposition to squareness, which according to him is a result of an identification process of higher abtraction. (shrink)

This is a collection of new investigations and discoveries on the theory of opposition by the best specialists from all over the world. The papers range from historical considerations to new mathematical developments of the theory of opposition including applications to theology, theory of argumentation and metalogic.

L'idée du cinéma comme " septième art ", Art total, synthèse des autres Arts, trouve son origine et ne se comprend vraiment que par rapport à la philosophie kantienne de l'Art. Cela peut sembler étonnant, mais c'est ce que fait apparaître de façon frappante, sur plusieurs points importants, l'étude du cinéma et de la manière dont les grands cinéastes et théoriciens se le sont eux-mêmes souvent représenté. La dimension philosophique, voire proprement métaphysique du cinéma, même du cinéma le plus simple (...) et le plus modeste, est en même temps liée à ce qui fait que le cinéma est un Art qui plaît tant populairement. Il y a là de quoi soupçonner ou entrevoir l'importance culturelle, sociale, morale et politique, peut-être, du cinéma le plus artistique. Il n'est pas nécessaire d'être spécialiste de philosophie pour lire l'ouvrage : tout ce qui est proprement philosophique y est expliqué simplement. Jean-Yves Chateau y montre à quelles conditions le cinéma peut être un Art, où se révèle avec une singulière clarté l'essence même de l'Art. En lui, sous des formes diverses, il y va toujours du monde lui-même et de la possibilité d'en faire un monde commun. (shrink)

The present book discusses all aspects of paraconsistent logic, including the latest findings, and its various systems. It includes papers by leading international researchers, which address the subject in many different ways: development of abstract paraconsistent systems and new theorems about them; studies of the connections between these systems and other non-classical logics, such as non-monotonic, many-valued, relevant, paracomplete and fuzzy logics; philosophical interpretations of these constructions; and applications to other sciences, in particular quantum physics and mathematics. Reasoning with contradictions (...) is the challenge of paraconsistent logic. The book will be of interest to graduate students and researchers working in mathematical logic, computer science, philosophical logic, linguistics and physics. (shrink)

Using methods of abstract logic and the theory of valuation, we prove that there is no paraconsistent negation obeying the law of double negation and such that $\neg(a\wedge\neg a)$ is a theorem which can be algebraized by a technique similar to the Tarski-Lindenbaum technique.

The aim of this paper is to redefine the notion of "heroism" through an investigation in the sociopolitics of popular Medias and especially the characters of Superheroes as they appear in comics of the late thirties and in the cinematographic industry since the nineties. This paper will pay a large tribute to the works of Gabriel Tarde, Henri Bergson and Gilles Deleuze whose concepts will be an imderlying constant reference. My purpose is to redefine the notion of heroism through the (...) notions of imitation and innovation, defined by Tarde as the fundamental principles of social life, and redefined by Deleuze as the collective expression of the primitive ontological forces of Repetition and Difference. Actually, the notion of imitation and innovation seem more appropriate to the study of popular culture phenomena than the statistic sociology of Durkheim. Based on that philosophical background, I will give an analysis of the political changes occurring in westem contemporary societies through an analysis of the representation of Superheroes. (shrink)