This paper presents a novel proof-theoretic account of dialogue coherence. It focuses on an abstract class of cooperative information-oriented dialogues and describes how their structure can be accounted for in terms of a multi-agent hybrid inference system that combines natural deduction with information transfer and observation. We show how certain dialogue structures arise out of the interplay between the inferential roles of logical connectives (i.e., sentence semantics), a rule for transferring information between agents, and a rule for information flow between (...) agents and their environment. The order of explanation is opposite in direction to that adopted in game-theoretic semantics, where sentence semantics (or a notion of valid inference) is derived from winning dialogue strategies. That approach and the current one may, however, be reconcilable, since we focus on cooperative dialogue, whereas the game-theoretic tradition concentrates on adversarial dialogue. (shrink)

Section 1 contrasts the approaches to Plato of F.M.Cornford and Gilbert Ryle, two of the early twentieth century’s leading Plato interpreters. Then I trace and evaluate attempts to discern in Plato’s Theaetetus a recognition of the role of the proposition. Section 2 focuses on the hunting of the proposition in Socrates’ Dream in the Theaetetus. Ryle, inspired by Logical Atomism, argued that Plato there anticipated an insight about the difference between names and propositions that Russell credited to Wittgenstein. I rehearse (...) difficulties for understanding the logos of the Dream as a proposition, preferring a reading of logos there as something like definition: a reading Wittgenstein also adumbrated. Section 3 examines attempts by writers such as Burnyeat and Kahn to find Plato allocating a starring role to the proposition in the argument at Theaetetus 185–6: perception, since it cannot grasp being, cannot grasp truth and hence cannot be knowledge. On their reading a grasp of being is understood as a grasp of something propositional. Problems for the propositional reading include Socrates’ talk of grasping ‘the truth of something’ (alētheia tinos), and the way the dialogue develops after 186. (shrink)

In the Foundations of Mathematics, Ramsey attempted to amend Principia Mathematica’s logicism to meet serious objections raised against it. While Ramsey’s paper is well known, some questions concerning Ramsey’s motivations to write it and its reception still remain. This paper considers these questions afresh. First, an account is provided for why Ramsey decided to work on his paper instead of simply accepting Wittgenstein’s account of mathematics as presented in the Tractatus. Secondly, evidence is given supporting that Wittgenstein was not moved (...) by Ramsey’s objection against the Tractarian account of arithmetic, and a suggestion is made to explain why Wittgenstein reconsidered Ramsey’s account in the early thirties on several occasions. Finally, a reading is formulated to understand the basis on which Wittgenstein argues against Ramsey’s definition of identity in his 1927 letter to Ramsey. (shrink)

The wantok system in the Solomon Islands and the Melanesian countries more broadly, strongly links to the practices of group identity and belonging, reciprocity, and caring for one’s relatives. It is a term used to express patterns of relationships that link people in families, tribes, islands, provinces, nationality and even more superficially at greater Melanesian sub-regional aggregates. Various aspects of the wantok system are called different names by distinct language groups in Papua New Guinea, Solomon Islands and Vanuatu. Nevertheless, the (...) word wantok originates from the English words ‘one talk’, which literally means in Melanesian pidgin, speakers of the same language. (shrink)

The paper contains a general argument for linguistic idealism, which it approaches by way of some considerations relating to the unity of the proposition and Tractarian metaphysics. Language exhibits a function–argument structure, but does it do so because it is reflecting how things are in the world, or does the relation of dependence run in the other direction? The paper argues that the general structure of the world is asymmetrically dependent on a metaphysically prior fact about language, namely that it (...) exhibits subject–predicate structure. (shrink)

Frege's philosophical writings, including the “logistic project,” acquire a new insight by being confronted with Kant's criticism and Wittgenstein's logical and grammatical investigations. Between these two points a non-formalist history of logic is just taking shape, a history emphasizing the Greek and Kantian inheritance and its aftermath. It allows us to understand the radical change in rationality introduced by Gottlob Frege's syntax. This syntax put an end to Greek categorization and opened the way to the multiplicity of expressions producing their (...) own intelligibility. This article is based on more technical analyses of Frege which Claude Imbert has previously offered in other writings. (shrink)

This paper presents a novel proof-theoretic account of dialogue coherence. It focuses on an abstract class of cooperative information-oriented dialogues and describes how their structure can be accounted for in terms of a multi-agent hybrid inference system that combines natural deduction with information transfer and observation. We show how certain dialogue structures arise out of the interplay between the inferential roles of logical connectives (i.e., sentence semantics), a rule for transferring information between agents, and a rule for information flow between (...) agents and their environment. The order of explanation is opposite in direction to that adopted in game-theoretic semantics, where sentence semantics (or a notion of valid inference) is derived from winning dialogue strategies. That approach and the current one may, however, be reconcilable, since we focus on cooperative dialogue, whereas the game-theoretic tradition concentrates on adversarial dialogue. (shrink)

Quoique l'on ne trouve qu'un nombre limité de références à Nicod dans les manuscrits de la période dite « intermédiaire » de Wittgenstein, une lecture attentive de La Géométrie dans le monde sensible s'avère pourtant décisive pour comprendre la nature du projet phénoménologique de Wittgenstein de la fin des années vingt. Nous nous proposons de montrer que la prise en compte ainsi que la reformulation du problème posé par Nicod en 1924, celui de la nature de la relation d'inclusion spatiale, (...) conduit Wittgenstein à remplacer dès 1929 l'ancien critère logique du simple et du complexe (celui du Tractatus logico-philosophicus) par un critère phénoménologico-grammatical inédit et désabsolutisé applicable à toute donnée visuelle quelle qu'elle soit. Plus généralement, la priorité donnée par Wittgenstein au visuel dans son « investigation phénoménologique des impressions sensorielles » trouve sa meilleure justification dans l'esquisse par Nicod d'une géométrie de la vision à la fois complète et indépendante. Nous montrons en particulier que les propriétés structurales du champ visuel mises au jour par Nicod dans sa construction (diversité et simultanéité des places sensibles, coloréité) sont tacitement utilisées par Wittgenstein pour justifier la possibilité d'une description phénoménologique conçue, précisément, comme description des places ou « localités » constitutives de cet espace perceptif. (shrink)

Wittgenstein’s “machines-as-symbols” are considered with respect to their historical sources and their symbolic and logical nature. Among these sources and precursors, along with Leonardo’s drawings of machines, there are illustrated “machine books”, a kind of book published in the period from the 16th to the 18th centuries which consist of pictures and descriptions of a variety of mechanical devices. Most probably, these books were one of Wittgenstein’s inspirations for his view of machines as components of language-games. The picture of homo (...) volans in Vrančić’s machine book possessed by Wittgenstein is taken as an example. In particular, homo volans is shown to contain patterns of logical laws and rules and to be abstractly interpretable as a logical symbol. A machine, taken as a symbol, is shown to be a precondition of a meaningful “overview” of a mechanical work that exceeds the limits of decidability, and to possess causal features if causality is understood teleologically and in a deeper sense of a “binding” life. (shrink)

What is the role of the environment, and of the information it provides, in cognition? More specifically, may there be a role for certain artefacts to play in this context? These are questions that motivate "4E" theories of cognition (as being embodied, embedded, extended, enactive). In his take on that family of views, Hajo Greif first defends and refines a concept of information as primarily natural, environmentally embedded in character, which had been eclipsed by information-processing views of cognition. He continues (...) with an inquiry into the cognitive bearing of some artefacts that are sometimes referred to as 'intelligent environments'. Without necessarily having much to do with Artificial Intelligence, such artefacts may ultimately modify our informational environments. -/- With respect to human cognition, the most notable effect of digital computers is not that they might be able, or become able, to think but that they alter the way we perceive, think and act. (shrink)

ABSTRACT: According to Michael Dummett, Wittgenstein rejects in the Philosophical Investigations the “realist” approach of the Tractatus, and replaces it with the idea that meaning is “use”; Wittgenstein, Dummett holds, draws the “metaphysical consequences” of this by subscribing to a form of non-realism. In this paper I defend a version of Dummett’s point that the Tractarian semantics is replaced in the Investigations by the notion that meaning is use, but I criticize his contention that Wittgenstein, as a consequence, subscribes to (...) some variety of metaphysical non-realism. (shrink)

Meinertsen’s unifier is discussed on the background of Aristotle’s distinction between four kinds of unity. It argued that Meinertsen combines two different kinds of unity that exclude each other. Only Aristotle’s first meaning of unity seems to be relevant for Meinertsen’s unifier. But this meaning applies literally only to spatial complexes. Its application to states of affairs is problematic because they are mostly not spatial. It is also problematic because unity in the first sense requires an agent. Meinertsen’s unifiers are (...) connectors between particulars and universals in states of affairs. It is objected that connectors in a state of affairs lead to a vicious infinite regress of further states of affairs. Meinertsen argues for his unifiers that states of affairs without them are non-mereological, that is, their existence is not entailed by the existence of their constituents. That does not seem a good argument if it is realised that a complex is not an additional entity and thus not existent if the existence of its parts is sufficient for its existence. It is also pointed out that the meaning of “mereological” involved is not related to the classical mereological calculus. (shrink)

Frege explained the notion of generality by stating that each its instance is a fact, and added only later the crucial observation that a generality can be inferred from an arbitrary instance. The reception of Frege’s quantifiers was a fifty-year struggle over a conceptual priority: truth or provability. With the former as the basic notion, generality had to be faced as an infinite collection of facts, whereas with the latter, generality was based on a uniformity with a finitary sense: the (...) provability of an arbitrary instance. (shrink)

The paper analyzes the ontological meaning of mood in Heidegger’s conception of Attunement, in order to relate this notion of Stimmung specifically to our “attunement” to a form of life, as conceived in Wittgenstein’s philosophy of language. It claims that moods spell out the constitutive impossibility to grasp and found the human experience as such. However, this impossibility is not a lack of human knowledge, but rather corresponds to the necessary opacity, indeterminability and groundlessness of every human experience, which make (...) it possible as such. The paper argues that the ontological mood of anxiety in Heidegger’s thought cannot be understood as a dark feeling, since it points to a constitutive sense of disorientation, which involves the impossibility to found and ensure the very familiarity of our ordinary experience. Moreover, the paper claims that the same impossibility is also involved in our “attunement” to language and to a form of life, as described by Wittgenstein in his Philosophical Investigations. By analyzing the mood of trust sketched out by Wittgenstein in On Certainty, the paper suggests that the ontological mood of trust, as the groundless certainty of our praxis, points to the very impossibility to found and ensure every human experience. From this perspective, moods reveal the groundlessness of human experience and make us acknowledge it. (shrink)

The state of recent as well as older research on social ontology suggests a paradigmatic approach, according to which it is our consciousness that must provide the framework for conceptualising the social. I, however, argue that Wittgenstein’s treatment of rule-following opens up a new horizon for the ontology of the social. The fact that the rules of our language are social in nature and that we need not be aware of them in order to follow them shifts the problem to (...) what lies behind consciousness. The ontological conceptualisation of the social must focus on our implicit knowledge instead, which is always an enabling condition for our consciousness: for we share some of this implicit knowledge with others, as can be seen from Wittgenstein and the case of language. (shrink)

The relation between Wittgenstein's philosophy of mathematics and mathematical Intuitionism has raised a considerable debate. My attempt is to analyse if there is a commitment in Wittgenstein to themes characteristic of the intuitionist movement in Mathematics and if that commitment is one important strain that runs through his Remarks on the foundations of mathematics. The intuitionistic themes to analyse in his philosophy of mathematics are: firstly, his attacks on the unrestricted use of the Law of Excluded Middle; secondly, his distrust (...) of non-constructive proofs; and thirdly, his impatience with the idea that mathematics stands in need of a foundation. These elements are Fogelin's starting point for the systematic reconstruction of Wittgenstein's conception of mathematics. (shrink)

The article discusses the case of Microsoft's Twitter chatbot Tay that “turned into a Nazi” after less than 24 hours from its release on the Internet. The first section presents a brief recapitulation of Alan Turing's proposal for a test for artificial intelligence and the way it influenced subsequent discussions in the philosophy of mind. In the second section, I offer a few arguments appealing for caution regarding the identification of an accomplished chatbot as a thinking being. These are motivated (...) principally by Ludwig Wittgenstein's discussions of mind and soul and by some Wittgensteinian philosophers' criticisms of AI endeavours. I will try to show that it is very difficult, if not impossible, to make sense of AIs such as chatbots as thinking beings, rather independently of their technical perfection and accomplishment. In the third section, the case of the “Nazi chatbot” Tay will offer me material for some light to be shed on the peculiar character of our interconnected concepts of thinking, soul and person and on the importance of their further ramified connections. (shrink)

Using new archival material, this article reconstructs the editorial history of Philosophical Grammar, an edition that Rush Rhees crafted from Wittgenstein's papers. Contrasting the often‐held view that Rhees, in editing Philosophical Grammar, arbitrarily interfered with Wittgenstein's Big Typescript, the article illuminates the work, motives and reasons that underlie Rhees’ editing. Although recent philological evidence supports his editorial decisions, Rhees, at the time, made them based on his desire to do justice to his understanding of Wittgenstein's philosophical orientation. Against this background, (...) purely text‐philological criticism of Philosophical Grammar seems to come from a philosophical culture that was alien to Rhees. (shrink)

This book is a synthesis of more than three decades of research into the concept of time and its semiotic nature. If traditional philosophy – and philosophy of time should be no exception – in the shadow of advancing biology can be said to have reached an impasse, one important reason for this, in harmony with Wittgenstein’s vision, appears to have been its lack of appropriate tools for explicating language. The present theory of time proceeds, accordingly, from the exploration of (...) temporal expressions in language as an evolutionary fact. It derives in a hypothetical, coherent feedback process of hierarchically ordered distinctions the semantics of time from its biologically dictated perceptual and cognitive-pragmatic origins. The corresponding abductive-regulative model is anchored in the assumption of biological rhythmization as the very foundation of perception and mental/physical action. Understood to originate in space and spatial perspective, time reveals itself as an instrument for temporal perspective on motion (events and situations) in a process of analysis, i.e., discontinuation of chaos made divisible and continuous by the rhythmical screen. Whereas traditional philosophy of time paid attention almost exclusively to the temporal category of tense, the biopragmatic model sees strong evidence in the perspectival nature of time for ascribing the decisive, and probably universal, role in temporal analysis to the linguistic category of aspect. Aspect may, according to the present findings, be assumed to partake already of change-of-state and cause-effect analysis without which man’s adaptation to new situations – and precondition for survival – would be inconceivable. The proposed model of space/time cognition, inspired by Hegelian dialectics, Heidegger-Gadamer’s hermeneutic circle and Peircean logic, makes Kantian a priori superfluous and liberates time from its enigmatic appearance. For the first time in temporal studies it thus appears possible to derive hypothetically linguistic expressions of time all the way from pretemporal, homogeneous continuity effected by biological rhythmization, via pretemporal metonymic (Gestalt), chunk-wise partitioning – as a general precondition for the perception and, based on primary metaphorization, the cognition of things, space and motion – to temporal analysis/discontinuation proper, primarily by aspectual perspective, and the subsequent synthesized, heterogeneous continuity of temporally ordered events. The conception of time, so disastrous for modern temporal logic, i.e., as moving object assigned extension, divisible continuity (‛linearity’) and direction, can be shown to have emerged as a result of secondary metaphorization. (shrink)

Cet article s'appuie sur la pensée de Wittgenstein pour comprendre comment des règles économiques agissent. L'étude (1993-2000) d'un Atelier de réparation de la RATP dans lequel une nouvelle règle de rendement a été introduite en 1993 met en évidence trois conclusions. Tout d'abord, dans la sélection des tâches, les opérateurs n'appliquent pas les règles de façon mécanique ; ils n'interprètent pas non plus les règles en faisant table rase des usages. Nos observations montrent que « suivre la règle est une (...) pratique ». En second lieu, les équipes développent des stratégies différentes pour obtenir la prime, ce qui illustre une autre thèse de Wittgenstein : « La signification de la règle se constitue dans l'usage. » Enfin, les opérateurs s'appuient sur les règles de l'usage pour trouver un certain usage de la règle. (shrink)

In this paper I explore a neglected discussion of vagueness put forward by Wittgenstein in his Philosophical Grammar (1932–34). In this work, unlike Philosophical Investigations (1953), Wittgenstein not only discusses the venerable Sorites paradox but provides a novel conception of vagueness using an analogy with coin tossing and converging intervals. As he sees it, the problematic picture of vagueness arises because we conflate aspects of the functioning of vague concepts with those of non-vague ones. Thus, while we accept that vague (...) concepts have no sharp cut-off points (are boundaryless), we nevertheless retain the idea that we can progress towards the penumbra the way we progress towards the cut-off points of non-vague concepts. As a potential remedy, Wittgenstein's analogy with coin tossing and converging intervals replaces this picture and provides an understanding of the functioning of vague concepts in which no notion of a progression arises. (shrink)

In this essay I set out to problematize the concepts of intersubjectivity and interaction in the theories of Germany's two foremost social philosophers: Jiirgen Habermas and Niklas Luhmann. To do so, I shall briefly reconstruct Husserl's phenomenological concept of intersubjectivity and its relationship with rational horizons and lifeworlds. I shall then demonstrate the importance of Husserl's thought in the theory of (rational) communicative action in Habermas. The third section deals with the radical rethinking of the subject (and hence intersubjectivity) in (...) the theory of Niklas Luhmann. My principal question will then be: is it possible to reconcile critical theory with systems theory? Or, alternatively: is intersubjectivity a reality or a useful fiction? (shrink)

Ce texte discute certaines conclusions d’un article récent de F. Mülhölzer et vise à montrer que le logicisme russellien a les moyens de résister à la critique que Wittgenstein lui adresse dans la partie III des Remarques sur les fondements desmathématiques.This paper discusses some conclusions of a recent article from F.Mülhölzer. It aims at showing that Russell’s logicism has the means to overcome the criticisms Wittgenstein expounded in Remarks on the Foundations of Mathematics, part III.

La confrontation Kant/Wittgenstein qui se dessine ici n'a pas pour objectif principal de présenter les doctrines des deux auteurs. Il s'agit plutôt de marier ces pensées qui ne le désirent pas, de profiter de la confrontation pour faire avancer le débat. Quel débat? Contrairement à I'ordre historique, il tire son origine de Wittgenstein: comment faut-il comprendre les prorèmes que soulève Wittgenstein, les interdits qu'il pose? Certaines de ses affirmations ne peuvent tout simplement pas être des jugements analytiques, aurait dit Kant. (...) Nombre de ses «remarques grammaticales» ne sont évidemment pas des tautologies, et la question se pose au moins de savoir comment elles sont possibles comme jugements analytiques. (shrink)