The justification of Bayes' rule by cognitive rationality principles is undertaken by extending the propositional axiom systems usually proposed in two contexts of belief change: revising and updating. Probabilistic belief change axioms are introduced, either by direct transcription of the set-theoretic ones, or in a stronger way but nevertheless in the spirit of the underlying propositional principles. Weak revising axioms are shown to be satisfied by a General Conditioning rule, extending Bayes' rule but also compatible with others, and weak updating (...) axioms by a General Imaging rule, extending Lewis' rule. Strong axioms (equivalent to the Miller–Popper axiom system) are necessary to justify Bayes' rule in a revising context, and justify in fact an extended Bayes' rule which applies, even if the message has zero probability. (shrink)

Despite its importance in various fields, analogical reasoning has not yet received a unified formal representation. Our contribution proposes a general scheme of inference that is compatible with different types of logic (deductive, probabilistic, non-monotonic). Firstly, analogical assessment precisely defines the similarity of two objects according to their properties, in a relative rather than absolute way. Secondly, analogical inference transfers a new property from one object to a similar one, thanks to an over-hypothesis linking two sets of properties. The belief (...) strength in the conclusion is then directly related to the belief strength in this meta-hypothesis. (shrink)

Two main schemes explain how a system adapts to its environment. Evolutionary models are grounded on three usual processes (variation, transmission, selection) acting at the population level. Learning models are concerned with the endogenous search for a better performance at the individual level. The first ones were initially favored by biology and the second well illustrated by game theory. The article examines first how game theory went to evolution and how biology later considered learning. It shows some examples of a (...) hybrid use of models of each type. It finally proposes a common framework for both types of models. (shrink)

The justification of Bayes' rule by cognitive rationality principles is undertaken by extending the propositional axiom systems usually proposed in two contexts of belief change: revising and updating. Probabilistic belief change axioms are introduced, either by direct transcription of the set-theoretic ones, or in a stronger way but nevertheless in the spirit of the underlying propositional principles. Weak revising axioms are shown to be satisfied by a General Conditioning rule, extending Bayes' rule but also compatible with others, and weak updating (...) axioms by a General Imaging rule, extending Lewis' rule. Strong axioms (equivalent to the Miller–Popper axiom system) are necessary to justify Bayes' rule in a revising context, and justify in fact an extended Bayes' rule which applies, even if the message has zero probability. (shrink)

Abduction was first introduced in the epistemological context of scientific discovery. It was more recently analyzed in artificial intelligence, especially with respect to diagnosis analysis or ordinary reasoning. These two fields share a common view of abduction as a general process of hypotheses formation. More precisely, abduction is conceived as a kind of reverse explanation where a hypothesis H can be abduced from events E if H is a good explanation of E. The paper surveys four known schemes for abduction (...) that can be used in both fields. Its first contribution is a taxonomy of these schemes according to a common semantic framework based on belief revision. Its second contribution is to produce, for each non-trivial scheme, a representation theorem linking its semantic framework to a set of postulates. Its third contribution is to present semantic and axiomatic arguments in favor of one of these schemes, ordered abduction, which has never been vindicated in the literature. (shrink)

L’article propose d’abord une version simplifiée d’une ontologie universelle, conçue comme un cadre général de description du monde matériel et mental. Il examine les notions d’entité, de propriété, de relation et de temporalité et leurs développements conjoints en termes de rapport entre les parties et le tout ou encore d’émergence d’une entité nouvelle. Il illustre ensuite les principes précédents en ce qui concerne la science économique, dont les entités de base sont les agents, les biens et les institutions. Il insiste (...) sur le couplage que cette dernière réalise entre leurs propriétés physiques ou psychologiques et le raisonnement qu’elle propose en termes d’équilibre et plus récemment d’apprentissage. Classification JEL : A12. (shrink)

RésuméEn dépit de son importance dans divers domaines, le raisonnement analogique n'a pas encore reçu de représentation formelle unifiée. Notre contribution propose un schéma d'inférence général, compatible avec différentes logiques (déductive, probabiliste, non monotone). Premièrement, un énoncé analogique définit précisément la similarité entre deux objets en fonction de leurs propriétés, de façon relative et non absolue. Deuxièmement, une inférence analogique transfère une propriété nouvelle d'un objet à un objet similaire, grâce à une hypothèse d'arrière-plan qui relie deux ensembles de propriétés. (...) Le degré de croyance dans la conclusion est alors directement relié au degré de croyance dans cette méta-hypothèse. (shrink)

The Sleeping Beauty problem is presented in a formalized framework which summarizes the underlying probability structure. The two rival solutions proposed by Elga and Lewis differ by a single parameter concerning her prior probability. They can be supported by considering, respectively, that Sleeping Beauty is “fuzzy-minded” and “blank-minded”, the first interpretation being more natural than the second. The traditional absent -minded driver problem is reinterpreted in this framework and sustains Elga’s solution.

The paper studies a specific adaptive learning rule when each player faces a unidimensional strategy set. The rule states that a player keeps on incrementing her strategy in the same direction if her utility increased and reverses direction if it decreased. The paper concentrates on games on the square [0,1]×[0,1]\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$[0,1]\times [0,1]$$\end{document} as mixed extensions of 2×2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$2\times 2$$\end{document} games. We study in general the (...) behavior of the system in the interior as well as on the borders of the strategy space. We then describe the system asymptotic behavior for symmetric, zero-sum, and twin games. Original patterns emerge. For instance, for the “prisoner’s dilemma” with symmetric initial conditions, the system goes directly to the symmetric Pareto optimum. For “matching pennies,” the system follows slowly expanding cycles around the mixed strategy equilibrium. (shrink)

Introduction. Bert HAMMINGA and Neil DE MARCHI: Préface. Bert HAMMINGA and Neil DE MARCHI: Idealization and the Defence of Economics: Notes Toward a History. Part I: General Observations on Idealization in Economics. Kevin D. HOOVER: Six Queries about Idealization in an Empirical Context. Bernard WALLISER: Three Generalization Processes for Economic Models. Steven COOK and David HENDRY: The Theory of Reduction in Econometrics. Maarten C.W. JANSSEN: Economic Models and Their Applications. Adolfo GARCÍA DE LA SIENRA: Idealization and Empirical Adequacy (...) in Economic Theory. Izabella NOWAKOWA and Leszek NOWAK: On Correspondence between Economic Theories. Uskali MÄKI: Isolation, Idealization and Truth in Economics. Part II: Case Studies of Idealization in Economics. Nancy CARTWRIGHT: Mill and Menger: Ideal Elements and Stable Tendencies. Wolfgang BALZER: Exchange Versus Influence: A Case of Idealization. Kees COOLS, Bert HAMMINGA, Theo A.F. KUIPERS: Truth Approximation by Concretization in Capital Structure Theory. Daniel M. HAUSMAN: Paul Samuelson as Dr. Frankenstein: When an Idealization Runs Amuck. Hugo A. KEUZENKAMP: What if an Idealization is Problematic? The Case of the Homogeneity Condition in Consumer Demand. Werner DIEDERICH: Nowak on Explanation and Idealization in Marx's 'Capital'. Gérard JORLAND: Idealization and Transformation. Jack BIRNER: Idealizations and Theory Development in Economics. Some History and Logic of the Logic Discovery. Discussions. Leszek NOWAK: The Idealizational Methodology and Economics. Replies to Diederich, Hoover, Janssen, Jorland and Mäki. (shrink)

The article examines two cases of adoption of evolutionary ways of thinking by modern economists: Nelson and Winter’s (Evolutionary Theory of Economic Change, 1982), and evolutionary game theory (1990s and after). In both cases, the authors explicitly refer to natural selection in an economic context. I show that natural selection is taken in two different senses, which correspond to two general conceptions of the principle of natural selection, one of which contains reproduction and heredity as key elements, whereas the other (...) does not. (shrink)

A new volume of philosophical essays by Bernard Williams. The book is a successor to Problems of the Self, but whereas that volume dealt mainly with questions of personal identity, Moral Luck centres on questions of moral philosophy and the theory of rational action. That whole area has of course been strikingly reinvigorated over the last deacde, and philosophers have both broadened and deepened their concerns in a way that now makes much earlier moral and political philosophy look sterile (...) and trivial. Moral Luck contains a number of essays that have contributed influentially to this development. Among the recurring themes are the moral and philosophical limitations of utilitarianism, the notion of integrity, relativism, and problems of moral conflict and rational choice. The work presented here is marked by a high degree of imagination and acuity, and also conveys a strong sense of psychological reality. The volume will be a stimulating source of ideas and arguments for all philosophers and a wide range of other readers. (shrink)

"In this exceptionally brilliant book, ranging effortlessly from Herodotus and Thucydides to Diderot and Nietzsche, Bernard Williams daringly asks--and still more daringly answers--one of the central questions of philosophy: what is the ...

What can--and what can't--philosophy do? What are its ethical risks--and its possible rewards? How does it differ from science? In Philosophy as a Humanistic Discipline, Bernard Williams addresses these questions and presents a striking vision of philosophy as fundamentally different from science in its aims and methods even though there is still in philosophy "something that counts as getting it right." Written with his distinctive combination of rigor, imagination, depth, and humanism, the book amply demonstrates why Williams was one (...) of the greatest philosophers of the twentieth century. Spanning his career from his first publication to one of his last lectures, the book's previously unpublished or uncollected essays address metaphysics, epistemology, and ethics, as well as the scope and limits of philosophy itself. The essays are unified by Williams's constant concern that philosophy maintain contact with the human problems that animate it in the first place. As the book's editor, A. W. Moore, writes in his introduction, the title essay is "a kind of manifesto for Williams's conception of his own life's work." It is where he most directly asks "what philosophy can and cannot contribute to the project of making sense of things"--answering that what philosophy can best help make sense of is "being human." Philosophy as a Humanistic Discipline is one of three posthumous books by Williams to be published by Princeton University Press. In the Beginning Was the Deed: Realism and Moralism in Political Argument was published in the fall of 2005. The Sense of the Past: Essays in the History of Philosophy is being published shortly after the present volume. (shrink)

We tend to suppose that the ancient Greeks had primitive ideas of the self, of responsibility, freedom, and shame, and that now humanity has advanced from these to a more refined moral consciousness. Bernard Williams's original and radical book questions this picture of Western history. While we are in many ways different from the Greeks, Williams claims that the differences are not to be traced to a shift in these basic conceptions of ethical life. We are more like the (...) ancients than we are prepared to acknowledge, and only when this is understood can we properly grasp our most important differences from them, such as our rejection of slavery. The author is a philosopher, but much of his book is directed to writers such as Homer and the tragedians, whom he discusses as poets and not just as materials for philosophy. At the center of his study is the question of how we can understand Greek tragedy at all, when its world is so far from ours. Williams explains how it is that when the ancients speak, they do not merely tell us about themselves, but about ourselves. _Shame and Necessity_ gives a new account of our relations to the Greeks, and helps us to see what ethical ideas we need in order to live in the modern world. (shrink)

What can--and what can't--philosophy do? What are its ethical risks--and its possible rewards? How does it differ from science? In Philosophy as a Humanistic Discipline , Bernard Williams addresses these questions and presents a striking vision of philosophy as fundamentally different from science in its aims and methods even though there is still in philosophy "something that counts as getting it right." Written with his distinctive combination of rigor, imagination, depth, and humanism, the book amply demonstrates why Williams was (...) one of the greatest philosophers of the twentieth century. Spanning his career from his first publication to one of his last lectures, the book's previously unpublished or uncollected essays address metaphysics, epistemology, and ethics, as well as the scope and limits of philosophy itself. The essays are unified by Williams's constant concern that philosophy maintain contact with the human problems that animate it in the first place. As the book's editor, A. W. Moore, writes in his introduction, the title essay is "a kind of manifesto for Williams's conception of his own life's work." It is where he most directly asks "what philosophy can and cannot contribute to the project of making sense of things"--answering that what philosophy can best help make sense of is "being human." Philosophy as a Humanistic Discipline is one of three posthumous books by Williams to be published by Princeton University Press. In the Beginning Was the Deed: Realism and Moralism in Political Argument was published in the fall of 2005. The Sense of the Past: Essays in the History of Philosophy is being published shortly after the present volume. (shrink)

Conceptual Foundations of Quantum Mechanics provides a detailed view of the conceptual foundations and problems of quantum physics, and a clear and comprehensive account of the fundamental physical implications of the quantum formalism. This book deals with nonseparability, hidden variable theories, measurement theories and several related problems. Mathematical arguments are presented with an emphasis on simple but adequately representative cases. The conclusion incorporates a description of a set of relationships and concepts that could compose a legitimate view of the world.

We tend to suppose that the ancient Greeks had primitive ideas of the self, of responsibility, freedom, and shame, and that now humanity has advanced from these to a more refined moral consciousness. Bernard Williams's original and radical book questions this picture of Western history. While we are in many ways different from the Greeks, Williams claims that the differences are not to be traced to a shift in these basic conceptions of ethical life. We are more like the (...) ancients than we are prepared to acknowledge, and only when this is understood can we properly grasp our most important differences from them, such as our rejection of slavery. The author is a philosopher, but much of his book is directed to writers such as Homer and the tragedians, whom he discusses as poets and not just as materials for philosophy. At the center of his study is the question of how we can understand Greek tragedy at all, when its world is so far from ours. Williams explains how it is that when the ancients speak, they do not merely tell us about themselves, but about ourselves. _Shame and Necessity_ gives a new account of our relations to the Greeks, and helps us to see what ethical ideas we need in order to live in the modern world. (shrink)

This book is a philosophically sophisticated and scientifically well-informed discussion of the moral and social issues raised by genetically engineering animals, a powerful technology which has major implications for society. Unlike other books on this emotionally charged subject, the author attempts to inform, not inflame, the reader about the real problems society must address in order to manage this technology. Bernard Rollin is both a professor of philosophy, and physiology and biophysics, and writes from a uniquely well-informed perspective on (...) this topic. The style is non-technical and anecdotal and will ensure that the book can be used on a wide range of courses on bioethics, biotechnology, veterinary medicine and public policy. The book could also appeal to a general, non-academic reader with a serious interest in genetic engineering. (shrink)

Writing in the wake of the breakup of the Soviet Union and Yugoslavia, the moral philosopher Bernard Williams considers the opposing claims of Rawlsian liberalism, with its emphasis on pluralism and procedural fairness, and communitarianism, which instead promotes more or less culturally homogeneous societies formed around shared values. Williams shares the communitarians’ critique of Rawls’s theory as excessively abstract, questioning whether a rational commitment to pluralism as the most just social arrangement can serve as a sufficiently binding social force. (...) He simultaneously resists, however, the conservative tendencies of the communitarians, particularly their dismissal of ethically motivated social critique. Grounded in the late philosophy of Wittgenstein, communitarians reject foundationalism, the notion that beliefs can be philosophically justified, instead regarding ideologically driven social arrangements as the result of inherently particular historical and environmental conditions. This perspective precludes rational reevaluation of a society’s status quo; if a society’s adoption of values does not depend on philosophically grounded principles, neither can those values be altered through a process of collective moral reasoning. For Williams, however, because pluralism is a condition of modern life with which even culturally homogenous communities must contend, members of modern societies are aware of alternatives to their own social model, leaving a space for self-critical reassessment. Finally, Williams suggests that the desire of cultural minorities for separate states in the post-Soviet geopolitical landscape underscores the limits of both pluralism and communitarianism, limits that all of us will need to grapple with as we confront the immediate social and political realities of modernity. (shrink)

These twenty-five essays span from ancient philosophy to Wittgenstein and express Williams’s conviction that studying the history of philosophy is an essential part of philosophy. Williams distinguishes a historical approach , which is focused on the context of a historical text and aims at the question of why some theory came up, from doing “history of philosophy,” aiming at a contribution to current philosophical debates by denying transhistorical identity and making use of the “alienation effect.”.

Since the advent of democracy in South Africa, there has been a concerted effort at reviving the notion of ubuntu. Variously conceived, it is seen as the authentic African ethical concept, a way of life, an authentic mode of being African, an individual ideal, the appropriate public spirit, a definition of life itself and the preferred manner of conducting public and private business. Thus, among other public displays of the spirit of ubuntu, the government of the day has deliberately chosen (...) its service delivery mantra and its public slogan as Batho Pele to animate, or perhaps pay obeisance to, ubuntu. In this paper we seek to advance arguments that question such a public, widespread, and concerted ‘ubuntu-isation’ of the intellectual, business, public and private lives. Our project follows two main lines of reasoning. We seek to show that the aggressive promotion of ubuntu in post-apartheid South Africa is an elitist project so conceived by the new black elite. It is conceived both as a restorative move that is aimed at securing the dignity of the black masses as well as an attempt at forging a so-called black identity. This line of reasoning will rely on similar historical cases on the continent that sought to aggressively promote an African mode of being, which coincided with both the end of colonialism and the rise of black elitism. We note that such attempts always ended in very public social and political failure. We seek to question the desirability of ubuntu as a mark/guide of the spirit of the nation. Here our critique shall be concentrated on the disjunct that exists between the metaphysical conditions necessary for the attainment of ubuntu and the stark ontological and ethical crisis facing the new elite and ‘our people’. (shrink)

From Bernard Boxill, professor of philosophy at the University of North Carolina at Chapel Hill and editor of Race and Racism, comes a tightly-argued, very illuminating book that will be essential reading for anyone interested in ...

This is the text of The Lindley Lecture for 1985, given by Bernard Williams, a British philosopher.