Reinforcement learning (RL) models of decision-making cannot account for human decisions in the absence of prior reward or punishment. We propose a mechanism for choosing among available options based on goal-option association strengths, where association strengths between objects represent previously experienced object proximity. The proposed mechanism, Goal-Proximity Decision-making (GPD), is implemented within the ACT-R cognitive framework. GPD is found to be more efficient than RL in three maze-navigation simulations. GPD advantages over RL seem to grow as task difficulty is increased. (...) An experiment is presented where participants are asked to make choices in the absence of prior reward. GPD captures human performance in this experiment better than RL. (shrink)

On the ethics of extending human life: healthy people have a right to carry on livingHumanity has long demonstrated a paradoxical ambivalence concerning the extension of a healthy human lifespan. Modest health extension has been universally sought, whereas extreme health extension has been regarded as a snare and delusion—a dream beyond all others at first blush, but actually something we are better off without. The prevailing pace of biotechnological progress is bringing ever closer the day when humanity will be able (...) to act on the latter view by rejecting a clear and present opportunity for much longer healthy lives. Indeed, some biogerontologists contend that that day has already arrived, to the extent that our hesitation in embarking on a vigorous “war on ageing” is already delaying the point at which a cure for ageing will be developed. Here I consider whether our present caution concerning the wisdom of truly curing ageing is likely to survive the increased scrutiny that it will receive in coming years as a result of these technical advances. I conclude that it will not, because of its irreconcilability with values that are more deeply held by the large majority of humanity than any values that argue against the quest for a cure. I further conclude that all the major current reasons given for not curing ageing are mere crutches to help us cope with the immutability of ageing that we have been brought up to accept. Our failure to set aside such irrationality is already shortening potential longevity—quite probably of those already alive today—to a staggering degree. Once we realise this, our determination to consign human ageing to history will be second …. (shrink)

Over recent years, evidence has been accumulating in favour of the free radical theory of aging, first proposed by Harman. Despite this, an understanding of the mechanism by which cells might succumb to the effects of free radicals has proved elusive. This paper proposes such a mechanism, based on a previously unexplored hypothesis for the proliferation of mutant mitochondrial DNA: that mitochondria with reduced respiratory function, due to a mutation or deletion affecting the respiratory chain, suffer less frequent lysosomal degradation, (...) because they inflict free radical damage more slowly on their own membranes. Once such a mutation occurs in a mitochondrion of a non‐dividing cell, therefore, mitochondria carrying it will rapidly populate that cell, thereby destroying the cell's respiratory capability. The accumulation of cells that have undergone this transition results in aging at the organismal level. The consistency of the hypothesis with known facts is discussed, and technically feasible tests are suggested, of both the proposed mechanism and its overall contribution to mammalian aging. (shrink)

The feasibility of reversing human aging within a matter of decades has traditionally been dismissed by all professional biogerontologists, on the grounds that not only is aging still poorly understood, but also many of those aspects that we do understand are not reversible by any current or foreseeable therapeutic regimen. This broad consensus has recently been challenged by the publication, by five respected experimentalists in diverse subfields of biogerontology together with three of the present authors, of an article (Ann NY (...) Acad Sci 959, 452–462) whose conclusion was that all the key components of mammalian aging are indeed amenable to substantial reversal (not merely retardation) in mice, with technology that has a reasonable prospect of being developed within about a decade. Translation of that panel of interventions to humans who are already alive, within a few decades thereafter, was deemed potentially feasible (though it was not claimed to be likely). If the prospect of controlling human aging within the foreseeable future cannot be categorically rejected, then it becomes a matter of personal significance to most people presently alive. Consequently, we suggest that serious public debate on this subject is now warranted, and we survey here several of the biological, social and political issues relating to it. BioEssays 24:667–676, 2002. © 2002 Wiley Periodicals, Inc. (shrink)

Current debates about “Darwinizing culture” have typically focused on the validity of memetics. In this article we argue that meme-like inheritance is not a necessary requirement for descent with modification. We suggest that an alternative and more productive way of Darwinizing culture can be found in the application of phylogenetic methods. We review recent work on cultural phylogenetics and outline six fundamental questions that can be answered using the power and precision of quantitative phylogenetic methods. However, cultural evolution, like biological (...) evolution, is often far from treelike. We discuss the problems reticulate evolution can cause for phylogenetic analyses and suggest ways in which these problems can be overcome. Our solutions involve a combination of new methods for the study of cultural evolution , and the triangulation of different lines of historical evidence. Throughout we emphasize that most debates about cultural phylogenies can only be settled by empirical research rather than armchair speculation. (shrink)

The present contribution to the continuing translation of the works of Heidegger into English under the editorship of J. Glenn Gray is one of the most valuable. The first-rate translation, preceded by an excellent Introduction, is by Albert Hofstadter, whose popular anthology, Philosophies of Art and Beauty, had included his translation of Heidegger's 1935 essay, "The Origin of the Work of Art." That essay, along with six other pieces, hitherto untranslated, make up the present volume--including the first essay of (...) Unterwegs zur Sprache, which was not included in the English translation, On the Way to Language. The volume also contains a translation of Heidegger's poem "Aus der Erfahrung des Denkens," under the title "The Thinker as Poet." Found here too are the two important essays "Building, Dwelling and Thinking," and "The Thing," which together represent the most important of Heidegger's all too brief but very suggestive treatments of the "world" as the "Foursome". Readers of Being and Time who consult these later essays will be surprised to discover what has come of the "world" in Heidegger's later thought, and in particular of the relationship of God to the world, a theme which was bracketed in Being and Time. As a whole this very valuable collection deals with the later Heidegger's highly aesthetic, highly poetic, view of Being and of Dasein's relationship to Being. These essays represent the final outcome of his use of the phenomenological method to approach Being; and they contain, if anything does, what Heidegger means by "overcoming metaphysics." If Heidegger's later thought is, as has been suggested, a Seinsmystik, it is no less a Seinsdichtung.--J. D. C. (shrink)

The feasibility of reversing human aging within a matter of decades has traditionally been dismissed by all professional biogerontologists, on the grounds that not only is aging still poorly understood, but also many of those aspects that we do understand are not reversible by any current or foreseeable therapeutic regimen. This broad consensus has recently been challenged by the publication, by five respected experimentalists in diverse subfields of biogerontology together with three of the present authors, of an article (Ann NY (...) Acad Sci 959, 452–462) whose conclusion was that all the key components of mammalian aging are indeed amenable to substantial reversal (not merely retardation) in mice, with technology that has a reasonable prospect of being developed within about a decade. Translation of that panel of interventions to humans who are already alive, within a few decades thereafter, was deemed potentially feasible (though it was not claimed to be likely). If the prospect of controlling human aging within the foreseeable future cannot be categorically rejected, then it becomes a matter of personal significance to most people presently alive. Consequently, we suggest that serious public debate on this subject is now warranted, and we survey here several of the biological, social and political issues relating to it. BioEssays 24:667–676, 2002. © 2002 Wiley Periodicals, Inc. (shrink)

We use the Newell Test as a basis for evaluating ACT-R as an effective architecture for cognitive engineering. Of the 12 functional criteria discussed by Anderson & Lebiere (A&L), we discuss the strengths and weaknesses of ACT-R on the six that we postulate are the most relevant to cognitive engineering.

The field of cognitive modeling has progressed beyond modeling cognition in the context of simple laboratory tasks and begun to attack the problem of modeling it in more complex, realistic environments, such as those studied by researchers in the field of human factors. The problems that the cognitive modeling community is tackling focus on modeling certain problems of communication and control that arise when integrating with the external environment factors such as implicit and explicit knowledge, emotion, cognition, and the cognitive (...) system. These problems must be solved in order to produce integrated cognitive models of moderately complex tasks. Architectures of cognition in these tasks focus on the control of a central system, which includes control of the central processor itself, initiation of functional processes, such as visual search and memory retrieval, and harvesting the results of these functional processes. Because the control of the central system is conceptually different from the internal control required by individual functional processes, a complete architecture of cognition must incorporate two types of theories of control: Type 1 theories of the structure, functionality, and operation of the controller, and type 2 theories of the internal control of functional processes, including how and what they communicate to the controller. This book presents the current state of the art for both types of theories, as well as contrasts among current approaches to human-performance models. It will be an important resource for professional and student researchers in cognitive science, cognitive-engineering, and human-factors.Contributors: Kevin A. Gluck, Jerry T. Ball, Michael A. Krusmark, Richard W. Pew, Chris R. Sims, Vladislav D. Veksler, John R. Anderson, Ron Sun, Nicholas L. Cassimatis, Randy J. Brou, Andrew D. Egerton, Stephanie M. Doane, Christopher W. Myers, Hansjorg Neth, Jeremy M Wolfe, Marc Pomplun, Ronald A. Rensink, Hansjorg Neth, Chris R. Sims, Peter M. Todd, Lael J. Schooler, Wai-Tat Fu, Michael C. Mozer, Sachiko Kinoshita, Michael Shettel, Alex Kirlik, Vladislav D. Veksler, Michael J. Schoelles, Jerome R. Busemeyer, Eric Dimperio, Ryan K. Jessup, Jonathan Gratch, Stacy Marsella, Glenn Gunzelmann, Kevin A. Gluck, Scott Price, Hans P. A. Van Dongen, David F. Dinges, Frank E. Ritter, Andrew L. Reifers, Laura Cousino Klein, Michael J. Schoelles, Eva Hudlicka, Hansjorg Neth, Christopher W. Myers, Dana Ballard, Nathan Sprague, Laurence T. Maloney, Julia Trommershauser, Michael S. Landy, A. Hornof, Michael J. Schoelles, David Kieras, Dario D. Salvucci, Niels Taatgen, Erik M. Altmann, Richard A. Carlson, Andrew Howes, Richard L. Lewis, Alonso Vera, Richard P. Cooper, and Michael D. Byrne. (shrink)

Lang, B. Philosophy and the manners of art.--Hofstadter, A. Freedom, enownment, and philosophy.--Mehta, J. L. A stranger from Asia.--Fox, D. A. A passage past India.--Rucker, D. Philosophy and the constitution of Emerson's world.--Schneider, H. W. The pragmatic movement in historical perspective.--Barnes, H. E. Reflections on myth and magic.--Cauvel, J. The imperious presence of theater.--Seay, A. Musical conservatism in the fourteenth century.--Hochman, W. R. The enduring fascination of war.--Davenport, M. M. J. Glenn Gray and the promise of wisdom.

In the final scene of Michel Tournier’s postcolonial novel La Goutte d’or, the protagonist, Idriss, shatters the glass of a Cristobal & Co. storefront window while operating a jackhammer in the working-class Parisian neighbourhood on the Rue de la Goutte d’or. Glass fragments fly everywhere as the Parisian police arrive. In La Goutte d’or, Tournier explores the identity construction of Idriss through a discussion of the role that visual images play in the development of a twentieth-century consciousness of the “Other.” (...) At the beginning of the novel, a French tourist takes a photograph of Idriss during her visit to the Sahara. The boy’s quest to reclaim his stolen image leads him from the Sahara to Marseille, and finally to the Rue de la Goutte d’or in Paris. The Rue de la Goutte d’or remains one the most cosmopolitan neighbourhoods of the city. In Tournier’s novel, the goutte d’or also corresponds to a symbolic object: a Berber jewel. It is the jewel that Idriss brings with him, but which he also subsequently loses upon his arrival in Marseille. From the very moment that the French tourist photographs him, a marginalization of Idriss’s identity occurs. Marginality, quite literally, refers to the spatial property of a location in which something is situated. Figuratively speaking, marginality suggests something that is on the edges or at the outer limits of social acceptability. In this essay, I explore the construction of the marginalized postcolonial self through an examination of the function of visual representation in the development of a postcolonial identity in La Goutte d’or. In the end, I conclude that the construction of a postcolonial identity is based upon fragmentation and marginalization, which ultimately leads its subject to create an identity based upon false constructions. (shrink)

Le Socrate de Xénophon et la démocratie présente une interprétation nuancée du témoignage de Xénophon sur l’attitude de Socrate à l’endroit de la démocratie athénienne. Cette étude conteste les interprétations qui ont été trop restrictives dans le choix des témoignages et trop négatives dans leurs conclusions. Elle tient compte, d’une part, des différents paramètres qui permettent de définir la démocratie ; d’autre part, des réalités de la démocratie athénienne. Les principaux textes pertinents proviennent des Mémorables. Nous traitons de la nature (...) de cet ouvrage et de la façon dont il expose l’attitude de Socrate à l’endroit des lois et des institutions du régime démocratique, notamment l’assemblée et le tirage au sort. Cette étude présente enfin une interprétation plus nuancée de la propre attitude de Xénophon à l’endroit de la démocratie, attitude qui a elle-même influé sur la façon dont on a, par le passé, évalué l’attitude de son Socrate.Xenophon’s Socrates and Democracy offers a balanced interpretation of Xenophon’s evidence for Socrates’ attitude to the Athenian democracy, arguing against interpretations that have been too selective in their evidence and too negative in their conclusions. It takes due account of the various parameters that define democracy and the realities of Athenian democracy. The main evidence is from Memorabilia. There is discussion of nature of this work, and then of how it expresses Socrates’ attitude to the laws of the democracy and other processes such as sortition and the assembly. The paper also offers a more balanced interpretation of Xenophon’s own attitude to democracy, which has influenced past assessments of the attitude of his Socrates. (shrink)

BackgroundWhen conducting research with Indigenous populations consent should be sought from both individual participants and the local community. We aimed to search and summarise the literature about methods for seeking consent for research with Indigenous populations.MethodsA systematic literature search was conducted for articles that describe or evaluate the process of seeking informed consent for research with Indigenous participants. Guidelines for ethical research and for seeking consent with Indigenous people are also included in our review.ResultsOf 1447 articles found 1391 were excluded (...) ; 56 were relevant and included. Articles were categorised into original research that evaluated the consent process or publications detailing the process of seeking consent and guidelines for ethical research. Guidelines were categorised into international ; national and state/regional/local guidelines. In five studies based in Australia, Canada and The United States of America the consent process with Indigenous people was objectively evaluated. In 13 other studies interpreters, voice recording, videos, pictures, flipcharts and “plain language” forms were used to assist in seeking consent but these processes were not evaluated. Some Indigenous organisations provide examples of community-designed resources for seeking consent and describe methods of community engagement, but none are evaluated. International, national and local ethical guidelines stress the importance of upholding Indigenous values but fail to specify methods for engaging communities or obtaining individual consent. In the ‘Grey literature’ concerns about the consent process are identified but no solutions are offered.ConclusionConsultation with Indigenous communities is needed to determine how consent should be sought from the community and the individual, and how to evaluate this process. (shrink)

Television medical dramas sometimes depict medical professionalism and bioethical issues, but their nature and extent are unclear. The authors systematically analysed the bioethical and professionalism content of one season each of Grey's Anatomy and House M.D., two of the most popular current television medical dramas. The results indicate that these programmes are rife with powerful portrayals of bioethical issues and egregious deviations from the norms of professionalism and contain exemplary depictions of professionalism to a much lesser degree.

This paper examines narrativism’s claim that the historical past cannot be known once and for all because it must be continuously re-described from the standpoint of the present. We argue that this claim is based on a non sequitur. We take narrativism’s claim that the past must be re-described continuously from the perspective of the present to be the result of the following train of thought: 1) “all knowledge is conceptually mediated”; 2) “the conceptual framework through which knowledge of reality (...) is mediated changes with every new generation of historians”; therefore (narrativism’s claim) “the historical past changes with every new generation of historians”. The idea of an unchanging past, for the narrativist, requires denying premise 1 (all knowledge is conceptually mediated”) and therefore rests on a problematic commitment to the chimerical notion of the past as it is in-itself, wie es eigentlich gewesen. We argue that the narrativist’s conclusion does not follow unless one adds a further premise, namely 3) “it is not possible to view reality through the categorial framework of historical agents”. If one asserts the possibility of grasping reality through the categorial framework of others, be they contemporary or past agents (as much philosophy of history written in an idealist key does), then one no longer has to accept the narrativist’s inference that since the past cannot be known in-itself or independently of conceptual mediation, then it cannot be known as it always was for the historical agents. Narrativism’s inference that the past cannot be known as it always was does not follow from premises 1 and 2 unless one smuggles in another problematic premise, premise 3. In this paper we defend the claim that the past can be known as it always was (not as it is in-itself) by invoking a different conception of the role of conceptual mediation in historical knowledge, one which assumes the possibility of viewing reality through the categorial framework of others. This notion of the role of conceptual mediation in historical knowledge is prevalent in the idealist tradition but, in the interest of brevity, we will defend this notion of mediacy by specific reference to the idealist philosophy of R.G. Collingwood. (shrink)

The Church of England By Law Established, in incidental payment for secular privilege, has submitted to the bonds of established clichá, in particular to the reproach that its rulers seem more concerned with the external or practical working of Anglican faith and ritual than with their intellectual definition and justification. This intellectual looseness remained unimportant in practice as long as a forceful anti–Roman spirit blew all waves of opinion in one practical direction. In time, however, that wind gradually lost force (...) and positive cross–currents of Anglican belief came to the public surface. The legislators of the sixteenth century had formulated the positive rules of the Thirty–Nine Articles and the Prayer Book in tolerantly broad language. They left no decisive teaching authority to explain their texts and to meet the challenge of shifting ritual and speculative doubt. Time has subjected both instruments to an everwidening range of individual interpretation especially since the early nineteenth century, when the Anglican monopoly of political, social and educational institutions was disputed by fresh tides of Protestant dissenters, renascent Catholics and nascent agnostics. To–day, as Mr. Cockshut wryly comments: “to throw doubt on the Anglican formularies is itself part of the Anglican tradition”. (shrink)