In this paper, we study the power and limitations of computing effectively generic sequences using effectively random oracles. Previously, it was known that every 2-random sequence computes a 1-generic sequence and every 2-random sequence forms a minimal pair in the Turing degrees with every 2-generic sequence. We strengthen these results by showing that every Demuth random sequence computes a 1-generic sequence and that every Demuth random sequence forms a minimal pair with every pb-generic sequence. Moreover, we prove that for every (...) comeager${\cal G} \subseteq {2^\omega }$, there is some weakly 2-random sequenceXthat computes some$Y \in {\cal G}$, a result that allows us to provide a fairly complete classification as to how various notions of effective randomness interact in the Turing degrees with various notions of effective genericity. (shrink)

A semimeasure is a generalization of a probability measure obtained by relaxing the additivity requirement to superadditivity. We introduce and study several randomness notions for left-c.e. semimeasures, a natural class of effectively approximable semimeasures induced by Turing functionals. Among the randomness notions we consider, the generalization of weak 2-randomness to left-c.e. semimeasures is the most compelling, as it best reflects Martin-Löf randomness with respect to a computable measure. Additionally, we analyze a question of Shen, a positive answer to which would (...) also have yielded a reasonable randomness notion for left-c.e. semimeasures. Unfortunately, though, we find a negative answer, except for some special cases. (shrink)

A set of infinite binary sequences ${\cal C} \subseteq 2$ℕ is negligible if there is no partial probabilistic algorithm that produces an element of this set with positive probability. The study of negligibility is of particular interest in the context of ${\rm{\Pi }}_1^0 $ classes. In this paper, we introduce the notion of depth for ${\rm{\Pi }}_1^0 $ classes, which is a stronger form of negligibility. Whereas a negligible ${\rm{\Pi }}_1^0 $ class ${\cal C}$ has the property that one cannot (...) probabilistically compute a member of ${\cal C}$ with positive probability, a deep ${\rm{\Pi }}_1^0 $ class ${\cal C}$ has the property that one cannot probabilistically compute an initial segment of a member of ${\cal C}$ with high probability. That is, the probability of computing a length n initial segment of a deep ${\rm{\Pi }}_1^0 $ class converges to 0 effectively in n.We prove a number of basic results about depth, negligibility, and a variant of negligibility that we call tt-negligibility. We provide a number of examples of deep ${\rm{\Pi }}_1^0 $ classes that occur naturally in computability theory and algorithmic randomness. We also study deep classes in the context of mass problems, examine the relationship between deep classes and certain lowness notions in algorithmic randomness, and establish a relationship between members of deep classes and the amount of mutual information with Chaitin’s Ω. (shrink)

This research examines the structure and development of the organic sesame network from Burkina Faso to explain the declining trend in organic sesame export. The paper addresses particularly the question whether the organic sesame network is structurally (re)shaped as a conventional mainstream market or whether it still presents a real alternative to conventional sesame production and trade. It is found that over the last decade organic sesame is increasingly incorporated into mainstream market channels. But contrary to the well-known case of (...) conventionalization in California, where organic agriculture grew into mainstream agro-food arrangements, this study illustrates a case where organic sesame agriculture shrank into mainstream agro-food arrangements. The weak coherence between the production and marketing nodes in the organic sesame chain resulted in failures to vertically mediate information, balance power relationships in and across sesame chains, build trust, and limit price volatility and speculation, resulting in a shrinking organic sesame market. For developing a viable alternative to conventional sesame trading, relations between production and trading nodes in the organic networks need to be strengthened through public–private partnerships, combined with other public and legal reinforcement. (shrink)

© 2017. The American Astronomical Society. All rights reserved.We present new observations of the low-mass companion to HD 984 taken with the Gemini Planet Imager as a part of the GPI Exoplanet Survey campaign. Images of HD 984 B were obtained in the J and H bands. Combined with archival epochs from 2012 and 2014, we fit the first orbit to the companion to find an 18 au orbit with a 68% confidence interval between 14 and 28 au, an eccentricity (...) of 0.18 with a 68% confidence interval between 0.05 and 0.47, and an inclination of 119°with a 68% confidence interval between 114°and 125°. To address the considerable spectral covariance in both spectra, we present a method of splitting the spectra into low and high frequencies to analyze the spectral structure at different spatial frequencies with the proper spectral noise correlation. Using the split spectra, we compare them to known spectral types using field brown dwarf and low-mass star spectra and find a best-fit match of a field gravity M6.5 ±1.5 spectral type with a corresponding temperature of K. Photometry of the companion yields a luminosity of log=2.88 ± 0.07 dex with DUSTY models. Mass estimates, again from DUSTY models, find an age-dependent mass of 34 ±1 to 95 ±4 M Jup. These results are consistent with previous measurements of the object. (shrink)

Dans ce livre, l’auteur élabore une critique de la notion de « banalité du mal » forgée par Hannah Arendt à partir du procès Eichmann en vue d’expliquer les crimes de masse. En reconnaissant, certes, que la banalité du mal est une formule qui a le mérite d’affirmer la dimension humaine du mal extrême « par opposition à l’idée de l’indicible d’un mal absolu et transcendant » (p. 117), Isabelle Delpla la qualifie néanmoins de « faux concept ». Del...

Ce texte a déjà paru dans Intermédialités : histoire et théorie des arts, des lettres et des techniques / Intermediality : History and Theory of the Arts, Literature and Technologies, n° 16, 2010, p. 105-128, puis sur Erudit.org. Nous remercions Laurent Guido de nous avoir autorisé à le reproduire ici. Depuis une vingtaine d'années, l'idée de mondialisation s'est imposée au sein des discours et des pratiques culturelles, dans un contexte où sont apparues de nouvelles techniques d'information et de - (...) Cinéma, animation et vidéo – GALERIE – Nouvel article. (shrink)

Georges Vigarello, après Le Propre et le sale et L'histoire culturelle du sport, nous propose au Seuil une Histoire du viol en grande partie consacrée aux XVIIIe et XIXe siècles. Il comble en partie une lacune historiographique sur un crime qui intéresse tout particulièrement l'histoire des femmes ainsi que les modalités relationnelles entre les sexes et rend son historicité à un crime trop souvent considéré comme intemporel. Il montre combien au XVIIIe la femme n'est pas considérée c..

Georges Vigarello, après Le Propre et le sale et L'histoire culturelle du sport, nous propose au Seuil une Histoire du viol en grande partie consacrée aux XVIIIe et XIXe siècles. Il comble en partie une lacune historiographique sur un crime qui intéresse tout particulièrement l'histoire des femmes ainsi que les modalités relationnelles entre les sexes et rend son historicité à un crime trop souvent considéré comme intemporel. Il montre combien au XVIIIe la femme n'est pas considérée c...

Georges Vigarello, après Le Propre et le sale et L'histoire culturelle du sport, nous propose au Seuil une Histoire du viol en grande partie consacrée aux XVIIIe et XIXe siècles. Il comble en partie une lacune historiographique sur un crime qui intéresse tout particulièrement l'histoire des femmes ainsi que les modalités relationnelles entre les sexes et rend son historicité à un crime trop souvent considéré comme intemporel. Il montre combien au XVIIIe la femme n'est pas considérée c...

Il De universalibus di Riccardo Brinkley è la seconda delle sette parti che costituiscono la Summa logicae. L'A., prima di fornire l'edizione del testo , conduce un'analisi dottrinale e comparativa. Perciò ne illustra struttura e contenuto, esplicitando il concetto di universale metafisico, la critica della concezione puramente semantica dell'universale, la natura dell'intentio universale, l'universale logico, la sua divisione. Brinkley esprime la sua contrarietà rispetto al concetto dell'universale logico come intentio in anima. La sezione successiva riguarda invece i cinque predicabili di (...) Porfirio, il genere, la specie, la differenza, il proprio e l'accidente. L'ultima parte del saggio è incentrata su alcune osservazioni comparative tra Brinkley e alcuni suoi contemporanei, come Guglielmo d'Ockham , Walter Burley , Giovanni Wyclif . L'A. conclude proponendo di considerare il De universalibus di Brinkley un testimone precoce dell'opposizione tardo medievale tra antiqui e moderni. In Brinkley l'universale metafisico ha il primato rispetto all'universale logico. Il Tractatus de universalibus è edito sulla base dei mss.: P = Praha, Narodní Knihovna, 396 8 , ff. 53rb-58va e L = Leipzig, UB, 1360, ff. 29vb-36va. Si fa riferimento, con la sigla GW all'edizione del primo capitolo del De universalibus. (shrink)

Quelles sont les opinions spéculatives de John Locke sur la nature de l’esprit et des idées et sur les conditions métaphysiques de la pensée et de la conscience? Faut-il en rester à la vision traditionnelle d’un Locke qui reste agnostique à propos de telles questions, au prétexte que leur traitement excède la méthode adoptée dans l’ Essai? Philippe Hamou a affronté ce problème et a entrepris de réévaluer la philosophie de l’esprit lockienne, dans une série de travaux qui illustrent l’intérêt (...) contemporain pour la métaphysique qui convient à cette épistémologie. La présente discussion situe la contribution de P. Hamou au sein des études récentes et propose quelques objections. (shrink)

"Leo Strauss: une bibliographie / Jean-Pierre Delange"--P. [279]-316.

resumo Esse artigo investiga a leitura que Shaftesbury fez de Marco Aurélio, a fim de comparar a visão estóica da individual ida de e da ide nt ida de pessoal com o conceito lockia no de “self” e, de ma ne i ra mais ge ral, com os mo dos pelos quais a filosofia mo de rna entendeu o si-me s mo. A ênfase recai sobre a conexão int r í nseca ent re sistema e s u b j e (...) t i v ida de no estoicismo imperial. Discute-se a re s i s t ê nc ia de autores cont e m p o r âneos em aceitar a descrição da alma ra c io nal dos estóicos como um “self”. Também se discute a aplicação que Mic hel Foucault fez do seu conceito de “subjetivação” à id é ia estóica de “si-me s mo ”. palavras-chave Estoicismo; self; identidade pessoal; Shaftesbury; Marco Aurélio; Foucault. (shrink)

Dans ce livre, l’auteur élabore une critique de la notion de « banalité du mal » forgée par Hannah Arendt à partir du procès Eichmann en vue d’expliquer les crimes de masse. En reconnaissant, certes, que la banalité du mal est une formule qui a le mérite d’affirmer la dimension humaine du mal extrême « par opposition à l’idée de l’indicible d’un mal absolu et transcendant » (p. 117), Isabelle Delpla la qualifie néanmoins de « faux concept ». Del..

Phillips & Silverstein (P&S, 2003) propose that NMDA-receptor dysfunction may be the fundamental neurobiological mechanism underlying and associating impaired holistic perception and cognitive coordination with schizophrenic psychopathology. We discuss how the P&S hypothesis shares different aspects of the weak central coherence account of autism from both theoretical and experimental perspectives. Specifically, we believe that neither those persons with autism nor those with schizophrenia integrate visuo-perceptual information efficiently, resulting in incongruous internal representations of their external world. However, although NMDA-hypofunction may be (...) responsible for perceptual impairments in schizophrenia and possibly autism, we suggest that it is highly unlikely that NMDA-hypofunction is specifically responsible for the autistic behavioral symptomology, as described by P&S in their target article. (shrink)

The ambiguous-cue task is composed of two-choice simultaneous discriminations involving three stimuli: positive (P), ambiguous (A) and negative (N). Two different trial types are presented: PA and NA. The ambiguous cue (A) served as an S- in PA trials, but as an S+ in NA trials. When using this procedure, it is typical to observe a less accurate performance in PA trials than in NA trials. This is called the ambiguous-cue effect. Recently, it was reported in starlings that the ambiguous-cue (...) effect decreases when the stimuli are presented on an angled (120°) panel. The hypothesis is that the angled panel facilitates that the two cues from each discrimination are perceived as a compound, precluding value transfer via a second-order conditioning mechanism. In this experiment, we used pigeons and a flat panel. Nevertheless, our data were quite similar to the previous data in starlings. We conclude that the form of the panel cannot explain the ambiguous-cue effect. Several alternatives to be explored in future experiments are suggested. The riddle of the ambiguous-cue problem still remains unsolved. (shrink)

The article reviews the book "Interpretive Reasoning," by Laurent Stern.