Ramsey’s theorem asserts that every k-coloring of $[\omega ]^n$ admits an infinite monochromatic set. Whenever $n \geq 3$, there exists a computable k-coloring of $[\omega ]^n$ whose solutions compute the halting set. On the other hand, for every computable k-coloring of $[\omega ]^2$ and every noncomputable set C, there is an infinite monochromatic set H such that $C \not \leq _T H$. The latter property is known as cone avoidance.In this article, we design a natural class of Ramsey-like theorems encompassing (...) many statements studied in reverse mathematics. We prove that this class admits a maximal statement satisfying cone avoidance and use it as a criterion to re-obtain many existing proofs of cone avoidance. This maximal statement asserts the existence, for every k-coloring of $[\omega ]^n$, of an infinite subdomain $H \subseteq \omega $ over which the coloring depends only on the sparsity of its elements. This confirms the intuition that Ramsey-like theorems compute Turing degrees only through the sparsity of its solutions. (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)

Jeffery Aubin,Dianne Cole,Julio Cesar Dias Chaves,Jonathan von Kodar,Anne-France Morand,Timothy Pettipiece,Paul-Hubert Poirier,Martin Voyer,Eric Crégheur.

This article maps out the lexical landscape of precision from the late seventeenth to the early eighteenth century and investigate the various meanings of precision, both as a word and a concept, within the Paris Observatory and beyond. It argues that precision was first an attribute of instruments supposed to produce numerical measurements, like clocks and divided circles or sectors attached to optical devices. Less often, precision was applied to observers, the handling of instruments, and observational methods, including mathematical corrections (...) applied to raw data. When all these aspects were combined the numerical result finally was also deemed to be precise. Moving to the debate about the shape of the Earth that shook the Academy of Sciences in the 1730s, it follows the way in which wider audiences were conveyed the various meanings of precision. Between the Cartesian resistance to the emergence of a professional science of precision and the pedagogical approach followed by the Newtonians such as Maupertuis, it argues that Cassini III embraced the professionalism of modern science, but did not feel that methodological precision was out of the reach of an educated public. While Maupertuis has seemed content with a discussion focusing on the precision of instruments and results, Cassini III set himself the hefty task of producing an accessible account of precision as a method of inquiry. (shrink)

In this paper, we investigate the way in which French artillery engineers met the challenge of air drag in the nineteenth century. This problem was especially acute following the development of rifled barrels, when projectile initial velocities reached values much higher than the speed of sound in air. In these circumstances, the Newtonian approximation according to which the drag was a force proportional to the square of the velocity was not nearly good enough to account for experimental results. This prompted (...) a series of theoretical and experimental investigations aimed at determining the correct law of air resistance. Throughout the nineteenth century, contrary to what happened before or after, ballistician were—with very rare exceptions—alone in trying to tackle the problem of air resistance. This was a complex problem where theoretical considerations, experimental results, and computational algorithms intermingled with one another, as well as with the development of new materials and doctrine in artillery. By carefully studying the reasons why ballisticians finally opted for a complex empirical law at the end of the nineteenth century, we show that military procedures for evaluating materials became a yardstick for assessing the worth of mathematical theories as well. In conclusion, we try to assess why military specialists were not able to face the challenges posed by World War I and required the help of civilian scientists and mathematicians. (shrink)

ArgumentOne of the first high-altitude observatories was a hotel. Established in 1823, the chalet on Mount Faulhorn became a highpoint of nineteenth-century science. In this paper, I take this mountain as my entry point into the examination of the special attraction that mountains exerted on scientists. I argue that Mount Faulhorn stood for three different conceptions of the usefulness of the mountain in science: (1) in observation networks, stations were usually chosen for pragmatic rather than scientific reasons, but mountains representedsingularspots (...) in such networks, which deserved special attention; (2) the mountain also was amicrocosmwhere altitude differences were thought to capture essential features of latitude differences; (3) the mountain was sometimes no more than amacro-toolfor the pursuit of science, just a middle ground between the heaven and the earth. (shrink)

The integration of learning cognitive agents in the research agenda is an important step in the evolution of economics. However, relying on a retrospective analysis of the treatment of decision making in economics, this article argues that the cognitive programme aims to justify rational behaviour in an equilibrium framework rather than to integration an interpretative conception of agents' behaviour. As a consequence, the level of generality of analytical results remains limited and economists miss the opportunity to establish a discussion with (...) other social sciences. In particular, it fails to analyse a class of situations related to the problem of knowledge creation and the subsequent learning paradox. Building on recent advances in heterodox cognitive science, we suggest a behavioural approach that discriminates different learning situations. If applied, this approach would permit a better understanding of human behaviour and a richer analysis of coordination mechanisms in unfamiliar environment with no loss of rigour. (shrink)

Logical Investigations (notably, The Thought) is one of the works wherein Frege voices his hostility to psychologism in logic, science, and semantics. Such hostility lies, arguably, behind his threefold conceptual distinction between thought (Gedanke), thinking (Denken), and ideas (Vorstellungen). In this essay I investigate, to begin with, Frege’s motivations for drawing the distinction and keeping thinking episodes (one of the meanings of ‘thoughts’ in English) out of the picture. It turns out, or so I argue, that psychologism threatens, on Frege’s (...) view, to destroy the objectivity requirement by which thoughts are defined as answerable contents. I then draw a connection between this feature in Frege’s view and an on-going debate in philosophy of mind and language over the nature of world-directed thoughts and show that the feature lies at the heart of the singularist stance. Finally, I show that, despite Frege’s own hostility to all that bears the mark of the subjective in logic, science, and semantics, a psychological argument can be mounted in support of singularism (i.e. the view that some of our thoughts are about particulars qua particulars) using his disparaged notion of idea (Vorstellung) and that, appearances notwithstanding, the argument is compatible with the objectivity requirement on answerable thought-contents. (shrink)

The key to this study lies in my own identity as a researcher who specializes in the fifteenth century and Franciscan reforms, especially the confrontation in eastern Central Europe between the theory of the via media based on a return to the Martianian Constitutions, and the Observance sub vicariis brought by Giovanni of Capistrano when he crossed the Alps in 1451.2 The major aspect of this is a view on the “pre-history” of the Libellus ad Leonem, which was written in (...) 1513 by Paolo Giustiniani and Pietro Quirini in preparation of the Fifth Lateran Council. This “pre-history” concerns a century of transformations of the links between the Observant reforms, humanist culture and the.. (shrink)

A function is diagonally non-computable if it diagonalizes against the universal partial computable function. D.n.c. functions play a central role in algorithmic randomness and reverse mathematics. Flood and Towsner asked for which functions h, the principle stating the existence of an h-bounded d.n.c. function implies Ramsey-type weak König’s lemma. In this paper, we prove that for every computable order h, there exists an ω\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\omega}$$\end{document} -model of h-DNR which is not a not (...) model of the Ramsey-type graph coloring principle for two colors and therefore not a model of RWKL. The proof combines bushy tree forcing and a technique introduced by Lerman, Solomon and Towsner to transform a computable non-reducibility into a separation over ω\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\omega}$$\end{document} -models. (shrink)

Jeffery Aubin ,Marie Chantal ,Dianne Cole ,Julio Chaves ,Cathelyne Duchesne ,Christel Freu ,Steve Johnston ,Brice Jones ,Amaury Levillayer ,Stéphanie Machabée ,Paul-Hubert Poirier ,Philippe Therrien ,Jonathan von Kodar ,Martin Voyer ,Jennifer Wees ,Eric Crégheur.

Jeffery Aubin,Serge Cazelais,Marie Chantal,Julio Cesar Dias Chaves,Cathelyne Duchesne,Steve Johnston,Louis Painchaud,Paul-Hubert Poirier,Tuomas Rasimus,Gaëlle Rioual,Maryse Robert,Eric Crégheur.

Jean Klein a été l'un des principaux passeurs de la non-dualité indienne (advaita) et du yoga en France. Il a exercé et continue d'exercer une influence considérable dans les cercles de chercheurs spirituels. Dans cet ouvrage, Ludovic Fontaine a choisi d'interviewer trois enseignants, trois des principaux élèves de Jean Klein, qui s'inscrivent de manière originale et ouverte dans la perspective de leur maître. Eric Baret, Francis Lucille, et Jean-Marc Mantel présentent ici leur parcours spirituel, leur perspective propre sur la (...) non-dualité, l'éveil, la nature de la réalité. Ludovic les interroge également sur leur méthode d'enseignement : comment transmettent-ils l'éveil? Quel est leur rapport aux traditions (advaita vedanta, tantrisme cachemirien, yoga)? Quelles pratiques préconisent-ils? Qu'est-ce que ces pratiques non-duelles peuvent changer dans notre vie? Chacun pourra trouver dans ces magnifiques entretiens des renseignements précieux sur le chemin vers la liberté et la joie."--Page 4 of cover. (shrink)

A better understanding of media effects on immigration attitudes is crucial for policy development and innovation. While many studies have focused on immigration discourses or the salience of this issue in print media and broadcast TV, few have looked at how different “media diets” influence immigration attitudes. Using two-wave panel data composed of 14,480 observations (7,240 individuals) from nine EU countries, this article specifically analyses the role of online and social media news consumption as well as media diet diversity on (...) Europeans’ perceptions of the economic and cultural impact of immigration. The results show that relying primarily on online or social media (compared to print newspapers) to get news, consuming news less frequently, or having a less diverse media diet all significantly and negatively influence people’s perceptions of the impact of immigration. Results and implications are discussed in light of today’s changing media landscape and news consumption habits. (shrink)

Nous présentons une étude fondée sur un corpus de transcriptions de consultations médicales, dans le cadre d’un projet interdisciplinaire qui explore la question des inégalités sociales de santé. L’objet de cet article est de montrer comment, en tant que linguistes familiers du traitement outillé des corpus, nous avons choisi d’aborder ce matériau qui fait l’objet de questionnements disciplinaires complémentaires, et quels éléments de caractérisation spécifiques nous sommes en mesure d’apporter en réponse à une demande émanant de la sphère médicale.

Traditional literature considers complex biometric sources such as words, letters and signatures for writer verification/identification. In this work the use of small segments of the handwritten stroke for writer verification is proposed. A grapheme is defined as the concatenation of smaller segments or fragments. Two models of grapheme are developed based on the idea that the segments are parts of a circle with or without direction. The average of Gray Level of the Perpendicular Line to the Skeleton and Local Binary (...) Pattern are adopted as descriptors. A database of 3,000 images of 50 writers, with 6 types of segments and with 10 samples per segment has been developed. A binary output support vector machine was applied as classifier. Thus, 50 classifiers were trained using 100 balanced data sets generated using subsampling of the majority class. Experiments are carried out with the proposed models, with an identity verification hit rate of 97 % on average. The positive results of experiments show that it is possible to achieve high precision in writer verification using segment of graphemes. (shrink)

The double etymology of religio found in Antiquity has generated much discussion. Between the proposition of Cicero and that of Lactantius, we find the ambivalent position of Augustine. The modern analysis of these passages, which is influenced by criteria of linguistics, was centered around the true origin of the word and its true meaning. However, Augustine is neither here nor there. This article uses a rhetorical analysis of these etymologies and considers them as proof in the argumentation. This approach allows (...) identifying the reasons that urge Augustine to choose one or the other according to the addressee. When he addressed the non-Christians, Augustine chose the etymology of Cicero (relegere) and, when he dealt with the controversies with the Manicheans, he chose the etymology based on religare. (shrink)

To Aristotle, spoken words are symbols, not of objects in the world, but of our mental experiences related to these objects. Presently there are two major strands of interpretation of Aristotle’s concept of the linguistic sign. First, there is the structuralist account offered by Coseriu (Geschichte der Sprachphilosophie. Von den Anfängen bis Rousseau, 2003 [1969], pp. 65–108) whose interpretation is reminiscent of the Saussurean sign concept. A second interpretation, offered by Lieb (in: Geckeler (Ed.) Logos Semantikos: Studia Linguistica in Honorem (...) Eugenio Coseriu 1921–1981, 1981) and Weidemann (in: Schmitter (Ed.) Geschichte der Sprachtheorie 2. Sprachtheorien der abendländischen Antike, 1991), says that Aristotle’s concept of the linguistic sign is similar to the one presented in Ogden and Richard’s (The meaning of meaning: A study of the influence of language upon thought and of the science of symbolism, 1970 [1923]) semiotic triangle. This paper starts off with an introductory outline of the so-called phýsei-thései discussion which started during presocratic times and culminated in Plato’s Cratylus. Aristotle’s concept of the linguistic sign is to be regarded as a solution to the stalemate position reached in the Cratylus. Next, a discussion is offered of both Coseriu’s and Lieb’s analysis. We submit that Aristotle’s concept of the linguistic sign shows features of both Saussure’s and Ogden and Richards’s sign concept but that it does not exclusively predict one of the two. We argue that Aristotle’s concept of the linguistic sign is based on three different relations which together evince his teleological as well empiricist point of view: one internal (symbolic) relation and two external relations, i.e. a likeness relation and a relation katà synthéken. (shrink)

Lors d’un entretien récent Natalie Zemon Davis soulignait opportunément : « […] the study of the past provides rewards for moral sensibility and tools for critical understanding. No matter how evil the times, no matter how immense the cruelty, some elements of opposition or kindness and godness emerge. No matter how bleak and constrained the situation, some forms of improvisation and coping take place. No matter what happens, people go on telling stories about it and bequeath them to the futu..

L’auteur propose d’interroger deux aspects de la temporalité psychique à l’œuvre dans les pratiques éducatives. D’une part, la modalité du temps qui s’articule au registre de la Loi et participe à son expression (temps du Surmoi), d’autre part ce qui tient à la dynamique des désirs, à l’interfantasmatisation, à l’assise imaginaire de l’éducation et qui participe au fondement du sens même de tout projet (de vie, ou professionnel) pour les adolescents.

Although robots can contribute to the understanding of biological behavior, they fail to model the processes by which humans cope with their environment. Both development and learning are characterized by complex relationships that require constant modification. Given present technology, robots can only model behaviors in specific situations and during discrete stages. Robots cannot master the complex relationships that are the hallmark of human behavior.

Modelling the semantic behaviour of expressives in such a way that one be in a position to predict some, at least, of their distinctive properties is the purpose of any theory aiming at accounting for so-called expressive meaning. In this paper, we review a semantic framework coined by its author the Theory of Bias. We show that the two-tiered account of the meaning of expressives (notably, sentential interjections and pejorative epithets) favored by this framework has the resources to provide a (...) consistent explanation of their semantic behaviour in prima facie awkward statements such as ‘alas, I am unfavorably disposed towards something’ or ‘that stupid Trump isn’t stupid’. On the critical side, we argue that, not being intended to account for the meaning of expressives alone, the theory has hard times explaining the unshiftability of their bias, as opposed to the shiftability of the bias of discourse particles —a further member, according to some authors, of the category of expressives lato sensu— and that it fails to pinpoint unpluggability as the crucial test for expressive content. We conclude that, in spite of its merits, the theory need be theoretically enhanced and methodologically sharpened. (shrink)

Parmi toutes les pensées que nous avons sur le monde, certaines portent sur des objets particuliers de façon plus directe (ou moins lâche) que les pensées dites descriptives et sont, pour cette raison, qualifiées de singulières. La pensée exprimée par l’énoncé : « Jean Nicod est mort en 1924 » n’est, intuitivement, pas la même que celle exprimée par l’énoncé : « L’auteur de la Géométrie dans le monde sensible est mort en 1924 », ne serait-ce que parce que la (...) seconde ne porte sur l’individu particulier auquel réfère le nom propre Jean Nicod (dans le premier énoncé) qu’indirectement, via la satisfaction par ce dernier d’un ensemble de conditions descriptives. La thèse selon laquelle notre espace cognitif serait peuplé d’authentiques pensées singulières n’est pourtant pas, loin s’en faut, triviale et mérite d’être évaluée à la lumière des différentes approches possibles du phénomène. Ce livre tente de le cerner en présentant et évaluant les théories sémantiques, épistémiques et cognitives les plus significatives de la pensée singulière. Il promeut une approche intégrée qui vise à donner son juste poids aux aspects mis en lumière par ces théories. Il est assorti d’un commentaire de deux extraits de texte: l’un, de Bertrand Russell, souvent considéré comme le locus classicus de la thèse singulariste et des théories épistémiques de l’accointance; l’autre, du philosophe américain contemporain Kent Bach, sur la portée de la conception essentialiste orthodoxe des pensées de re. (shrink)

A partir d'une relecture de l'oeuvre de Wittgenstein étudie sa réfutation des théories philosophiques sur l'existence d'un champ propre aux sensations visuelles, ainsi que son projet phénoménologique de description de l'espace visuel.

Jeffery Aubin | : Les Diuinae institutiones de Lactance sont souvent citées lorsqu’il s’agit d’analyser le passage du mot religio de la langue latine à la pensée du christianisme. On ne doit toutefois pas lire ce texte du ive siècle de notre ère avec la conception moderne du mot religion. Les sociologues du xxe siècle ont élaboré des définitions de la religion à partir de l’opposition sacré/profane, mais cette dichotomie n’est toutefois pas une catégorie interprétative valide dans l’ouvrage de (...) Lactance. Non seulement il oppose ces deux notions que très rarement, mais la conception de sacer et de profanus diffère des définitions qui se sont imposées depuis un siècle. L’utilisation de concepts modernes pour l’analyse des Diuinae institutiones constitue dès lors un frein à la compréhension des notions de religion, sacré et profane dans l’ouvrage de Lactance. | : The Diuinae institutiones of Lactantius are often referred to when analyzing the transition of the word religio from Latin to Christian thought. However, one should not read this fourth century A.D. text with the modern definition of religion in mind. Twentieth century sociologists put forth definitions of religion based on the sacred-profane opposition, but this dichotomy is not a valid category for the interpretation of religio in the book of Lactantius. Not only does he scarcely oppose these two terms, but also the very notion of sacer and profanus differ from the received definitions of the last century. Therefore, the use of modern concepts is a stumbling block for the understanding of the terms religion, sacred and profane in the Diuinae institutiones of Lactantius. (shrink)

In everyday situations, and particularly in some sport and working contexts, humans face an inherently unpredictable and uncertain environment. All sorts of unpredictable and unexpected things happen but typically people are able to skillfully adapt. In this paper, we address two key questions in cognitive science. First, how is an agent able to bring its previously learned skill to bear on a novel situation? Second, how can an agent be both sensitive to the particularity of a given situation, while remaining (...) flexibly poised for many other possibilities for action? We will argue that both the sensitivity to novel situations and the sensitivity to a multiplicity of action possibilities are enabled by the property of skilled agency that we will call metastable attunement. We characterize a skilled agent’s flexible interactions with a dynamically changing environment in terms of metastable dynamics in agent-environment systems. What we find in metastability is the realization of two competing tendencies: the tendency of the agent to express their intrinsic dynamics and the tendency to search for new possibilities. Metastably attuned agents are ready to engage with a multiplicity of affordances, allowing for a balance between stability and flexibility. On the one hand, agents are able to exploit affordances they are attuned to, while at the same time being ready to flexibly explore for other affordances. Metastable attunement allows agents to smoothly transition between these possible configurations so as to adapt their behaviour to what the particular situation requires. We go on to describe the role metastability plays in learning of new skills, and in skilful behaviour more generally. Finally, drawing upon work in art, architecture and sports science, we develop a number of perspectives on how to investigate metastable attunement in real life situations. (shrink)