L'œuf de ver à soie qui se prête à de nombreuses recherches génétiques et physiologiques a été assimilé à un volume géométrique simple afin qu'on puisse calculer aisément l'aire de sa surface totale et son volume. On a d'abord cherché à justifier le modèle géométrique proposé grâce à une étude expérimentale et statistique. On a ensuite établi les formules mathématiques utiles. Enfin on a discuté de l'approximation donnée par ces formules et de leur signification biologique.The egg of the silkworm which (...) permits a lot of genetical and physiological researches has been assimilated to a simple geometric volume, so that the area of its total surface and its volume might be easily calculated. First we have tried to justify the geometrical model which is proposed by means of an experimental and statistical study. We have then demonstrated the useful mathematical formulas. Finally we have discussed the approximation given by these formulas and their biological significance.Das Seidenraupenei, das viele genetische und physiologische Forschungen ermöglicht, hat man mit einem einfachen geometrischen Modell verglichen, um seine ganze Fläche und sein Volumen leicht rechnen zu können. Zuerst hat man versucht, das vorgeschlagene geometrische Modell dank einer experimentalen und statistischen Arbeit zu rechtfertigen. Dann sind die nötigen mathematischen Formeln festgesetzt worden. Zuletzt hat man die durch diese Formeln gegebenen Annäherungen und ihre biologischen Bedeutung erörtert. (shrink)
Professor Sir Roger Penrose's work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. The first volume covers the beginnings of a career that is ground-breaking from the outset. Inspired by courses given by Dirac and Bondi, much of the early (...) published work involves linking general relativity with tensor systems. Among his early works is the seminal 1955 paper, 'A Generalized Inverse for Matrices', his previously unpublished PhD and St John's College Fellowship theses, and from 1967, his Adam's Prize-winning essay on the structure of space-time. Add to this his 1965 paper, 'Gravitational collapse and space-time singularities', and the 1967 paper that introduced a remarkable new theory, 'Twistor algebra', and this becomes a truly stellar procession of works on mathematics and cosmology. (shrink)
Professor Sir Roger Penrose's work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. Many important realizations concerning twistor theory occurred during the short period of this third volume, providing a new perspective on the way that mathematical features of the (...) complex geometry of twistor theory relate to actual physical fields. Following on from the nonlinear graviton construction, a twistor construction was found for (anti-)self-dual electromagnetism allowing the general (anti-)self-dual Yang-Mills field to be obtained. It became clear that some features of twistor contour integrals could be understood in terms of holomorphic sheaf cohomology. During this period, the Oxford research group founded the informal publication, Twistor Newsletter. This volume also contains the influential Weyl curvature hypothesis and new forms of Penrose tiles. (shrink)
Professor Sir Roger Penrose's work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. Among the new developments that occurred during this period was the introduction of a particular notion of 'quasi-local mass-momentum and angular momentum', the topic of Penrose's Royal (...) Society paper. Many encouraging results were initially obtained but, later, difficulties began to emerge and remain today. Also, an extensive paper (with Eastwood and Wells) gives a thorough account of the relation between twistor cohomology and massless fields. This volume witnesses Penrose's increasing conviction that the puzzling issue of quantum measurement could only be resolved by the appropriate unification of quantum mechanics with general relativity, where that union must involve an actual change in the rules of quantum mechanics as well as in space-time structure. Penrose's first incursions into a possible relation between consciousness and quantum state reduction are also covered here. (shrink)
Professor Sir Roger Penrose's work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. Developing ideas sketched in the first volume, twistor theory is now applied to genuine issues of physics, and there are the beginnings of twistor diagram theory (an (...) analogue of Feynman Diagrams). This collection includes joint papers with Stephen Hawking, and uncovers certain properties of black holes. The idea of cosmic censorship is also first proposed. Along completely different lines, the first methods of aperiodic tiling for the Euclidean plane that come to be known as Penrose tiles are described. This volume also contains Penrose's three prize-winning essays for the Gravity Foundation (two second places with both Ezra Newman and Steven Hawking, and a solo first place for 'The Non-linear graviton'). (shrink)
In Reasons and the Good Roger Crisp answers some of the oldest questions in moral philosophy. Fundamental to ethics, he claims, is the idea of ultimate reasons for action; and he argues controversially that these reasons do not depend on moral concepts. He investigates the nature of reasons themselves, and how we come to know them. He defends a hedonistic theory of well-being and an account of practical reason according to which we can give some, though not overriding, priority (...) to our own good over that of others. (shrink)
The categories of reason and faith are often contrasted. When reason gives out, we are told that we have to rely on faith. Such exhortations are made particularly in the context of religion. When for instance, we face some personal tragedy which may well seem inexplicable, we are told that faith can help us through it. Very often faith is referred to in a vacuum. Presumably faith in God is usually meant, but all too often God drops out of the (...) picture, and it seems that all we need is faith, not faith in anything or anyone, but just faith. We are thus encouraged to add what seems to be a magic ingredient to our lives, which can transform everything. Perhaps at the back of such thinking lies some Calvinist notion of the corrupt character of human reason. As a result it may seem that we cannot rely on our judgment, which is the product of the fallen and sinful nature of humanity. Instead we must depend on ‘faith’ which may, or may not, be given us by the grace of God. (shrink)
A rational person doesn’t believe just anything. There are limits on what it is rational to believe. How wide are these limits? That’s the main question that interests me here. But a secondary question immediately arises: What factors impose these limits? A first stab is to say that one’s evidence determines what it is epistemically permissible for one to believe. Many will claim that there are further, non-evidentiary factors relevant to the epistemic rationality of belief. I will be ignoring the (...) details of alternative answers in order to focus on the question of what kind of rational constraints one’s evidence puts on belief. Our main question concerns how far epistemic permission and obligation can come apart.1 Suppose I am epistemically permitted to believe P, i.e., it would not be irrational for me to believe it. Am I thereby obliged to believe P, or are other options rationally available to me?2 Might I be equally rational in remaining agnostic about P, or even believing not-P? Or could even a slightly stronger or weaker degree of confidence be just as reasonable? (shrink)
I argue that its appearing to you that P does not provide justification for believing that P unless you have independent justification for the denial of skeptical alternatives – hypotheses incompatible with P but such that if they were true, it would still appear to you that P. Thus I challenge the popular view of ‘dogmatism,’ according to which for some contents P, you need only lack reason to suspect that skeptical alternatives are true, in order for an experience as (...) of P to justify belief that P. I pursue three lines of objection to dogmatism, having to do with probabilistic reasoning, considerations of future or hypothetically available justification, and epistemic circularity. I briefly sketch a fall-back position which avoids the problems raised. (shrink)
The Inexact and Separate Science of Economics represents the most ambitious attempt to provide a systematic account of economic methodology since the first edition of Blaug's The Methodology of Economics. As such, it has been the subject of extensive critical commentary. For all the attention it has received, however, some important aspects of the book's thesis have not been developed properly. Two important ones are what might be called, following the terminology used in the experimental economics literature, the ‘framing effect’ (...) of Hausman's definition of economics, and the significance of Hausman's claim that economists are committed to developing economics as a ‘separate’ science. To understand these points it is important to make explicit the position from which Hausman approaches the philosophy of science. (shrink)
Roger North's The Musicall Grammarian 1728 is a treatise on musical eloquence in all its branches. Of its five parts, I and II, on the orthoepy, orthography and syntax of music, constitute a grammar; III and IV, on the arts of invention and communication, form a rhetoric; and V, on etymology, consists of a history. Two substantial chapters of commentary introduce the text, which is edited here for the first time in its entirety: Jamie Kassler places his treatise within (...) the broader context not only of North's musical and non-musical writings but also their relation to the intellectual ferment of the seventeenth and eighteenth centuries and Mary Chan describes physical and textual aspects of the treatise as evidence for North's processes of thinking about musical thinking. (shrink)
I believe that Tom is the proud father of a baby boy. Why do I think his child is a boy? A natural answer might be that I remember that his name is ‘Owen’ which is usually a boy’s name. Here I’ve given information that might be part of a causal explanation of my believing that Tom’s baby is a boy. I do have such a memory and it is largely what sustains my conviction. But I haven’t given you just (...) any causally relevant information, I’ve given my grounds for my belief. I’ve given reasons that might justify me in supposing that Tom’s baby is a boy. Less naturally, the question might be taken as a request for a broader causal explanation of my holding this belief. Appropriate answers might cite all manner of facts concerning the evolution of the human race, why I chose to pursue philosophy and hence came to know Tom, the mechanisms of email transmission, the firing of various neurons, the circumstances of concept formation as a result of which I’m able to grasp the thought that Tom’s baby is a boy, and so on. It is an interesting question what distinguishes the narrower set of answers that I first suggested. I won’t pursue that here. I assume you have a good enough sense of the distinction I’m drawing. We might call the narrower set of answers justifying reasons, the kind of reasons I might cite in justifying my belief. Answers of the first sort are clearly relevant to epistemological evaluation. In assessing whether you know p or are rational in believing it to the degree you do, I will naturally want to consider what reasons you have for your belief. In deliberating myself about whether to believe p, in seeking an answer to the question of whether p, I will naturally consider what reasons or grounds I have to suppose that p. But what I want to focus on here is how explanations of the broader sort bear on such questions as whether to believe p. From a third-person perspective we can ask, ‘In assessing the epistemic status of S’s belief that p, what is the relevance of causal information that lies outside of the realm of justifying reasons?’ From the first-person standpoint we can ask ‘In seeking to answer whether p, how should such causal information affect my deliberations?’ At first it might seem that such broader causal information could have little relevance if any. Like any belief my belief that p can be traced back to innumerable causes from far and wide.. (shrink)
Professor Sir Roger Penrose is one of the truly original thinkers of our time. He has made several remarkable contributions to science, from quantum physics and theories of human consciousness to relativity theory and observations on the structure of the universe. Unusually for a scientist, some of his ideas have crossed over into the public arena. Now his work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for (...) the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. (shrink)
Professor Sir Roger Penrose's work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. Publication of The Emperor's New Mind (OUP 1989) had caused considerable debate and Penrose's responses are included in this volume. Arising from this came the idea that (...) large-scale quantum coherence might exist within the conscious brain, and actual conscious experience would be associated with a reduction of the quantum state. Within this collection, Penrose also proposes that a twistor might usefully be regarded as a source (or 'charge') for a massless field of spin 3/2, suggesting that the twistor space for a Ricci-flat space-time might actually be the space of such possible sources. Towards the end of the volume, Penrose begins to develop a quite different approach to incorporating full general relativity into twistor theory. This period also sees the origin of the Diósi-Penrose proposal. (shrink)
Professor Sir Roger Penrose's work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. This sixth volume describes an actual experiment to measure the length of time that a quantum superposition might last (developing the Diósi-Penrose proposal). It also discusses the (...) significant progress made in relation to incorporating the 'googly' information for a gravitational field into the structure of a curved twistor space. Penrose also covers such things as the geometry of light rays in relation to twistor-space structures, the utility of complex numbers in drawing three-dimensional shapes, and the geometrical representation of different types of musical scales. The turn of the millennium was also an opportunity to reflect on progress in many areas up until that point. (shrink)
the symmetry of our evidential situation. If our confidence is best modeled by a standard probability function this means that we are to distribute our subjective probability or credence sharply and evenly over possibilities among which our evidence does not discriminate. Once thought to be the central principle of probabilistic reasoning by great..
RésuméĽutilisation de tests statistiques sans en connaître les conditions de validité peut être fort discutable. Appliqués à des résultats déjà obtenus, il peuvent conduire à des conclusions erronées. Ľemploi de la statistique, au niveau de la planification de ľexpérience déjà, permet ?on;augmenter très généralement ?on;une façon sensible la précision des résultats.It may be debatable to use statistical tests without knowing the conditions under which they are valid. If tests are applied to result which have already been obtained, the conclusion drawn (...) may be incorrect. The use of statistics at the level of experimental design can often considerably improve the precision of the results.ZusammenfassungDie Verwendung statistischer Tests, ohne deren Gültigkeitsbedingungen zu kennen, kann sehr fraglich sein. Auf schon vorhandene Ergebnisse angewandt, können sie zu falschen Schlüssen führen. Eine Planung des Versuchsprogramms mit Hilfe der Statistik kann oft die Genauigkeit der Resultate merklich verbessern. (shrink)
It is generally agreed by historians of modern thought that, at the end of the nineteenth century and the beginning of the twentieth, philosophers in the German-speaking world identified and defined a type or species of knowledge whose peculiar independent status had hitherto been largely overlooked. It was developed, clarified, and, with a sharpened awareness of its unique possibilities, made to work in practice above all by Dilthey, Windelband, Rickert and their numerous followers; and, to a degree, also by Max (...) Weber. The general name by which it was, and is, most often referred to is ‘ Verstehen ’—understanding. It has to be admitted that it was from the first, and remains to this day, a highly problematic and hotly disputed concept. Positivists, materialists, behaviourists and monists of all kinds—all those whose ideal is a single structure of organized systematic knowledge—have tended to view it with deep suspicion, and even to deny its existence altogether, claiming that it is wholly illusory and doomed to disappear before the inevitable advance of positive scientific method. However that may be, it will not be my purpose in this paper to enter into these difficult controversies. It may indeed be that no watertight definition of it is possible; that its putative boundaries with other forms or types of knowledge are vague and shifting; and even that there is no ultimate discontinuity in principle between it and the knowledge we gain from other spheres of research and investigation. (shrink)
What is the relation of the biological to the social sciences? Fierce battles are being currently fought over this question and much hangs on the answer. If society is taken as an irreducible category which can only be understood in its own terms, the social sciences can feel safe from the sinister designs of other disciplines. Yet it is a commonplace that cultures vary, and we humans are prone to look at the differences rather than the similarities between them. The (...) result can be a thoroughgoing relativism. If culture cannot be understood by means of any non-cultural categories, cultural differences themselves can be accepted as the ultimate truth about man. When everything is cultural, even the notion of a non-cultural category can seem to be a ludicrous contradiction in terms. The categories with which we think are the product of our culture, or so we are told. Instead of our being able to understand culture in terms of anything beyond itself, our understanding appears totally moulded by the society to which we belong. Any theory can thus be seen as merely the expression of the beliefs of a particular society. (shrink)
One of the most important philosophers of recent times, Elizabeth Anscombe wrote books and articles on a wide range of topics, including the ground-breaking monograph Intention. Her work is original, challenging, often difficult, always insightful; but it has frequently been misunderstood, and its overall significance is still not fully appreciated. This book is the first major study of Anscombe's philosophical oeuvre. In it, Roger Teichmann presents Anscombe's main ideas, bringing out their interconnections, elaborating and discussing their implications, pointing out (...) objections and difficulties, and aiming to give a unified overview of her philosophy. Many of Anscombe's arguments are relevant to contemporary debates, as Teichmann shows, and on a number of topics what Anscombe has to say constitutes a powerful alternative to dominant or popular views. Among the writings discussed are Intention, "Practical Inference," "Modern Moral Philosophy," "Rules, Rights and Promises," "On Brute Facts," "The First Person," "The Intentionality of Sensation," "Causality and Determination," An Introduction to Wittgenstein's Tractatus, "The Question of Linguistic Idealism," and a number of other pieces, including some that are little known or hard to obtain. A complete bibliography of Anscombe's writings is also included. Ranging from the philosophy of action, through ethics, to philosophy of mind, metaphysics, and the philosophy of logic and language, this book is a study of one of the most significant bodies of work in modern philosophy, spanning more than fifty years, and as pertinent today as ever. (shrink)
I treat you as a thermometer when I use your belief states as more or less reliable indicators of the facts. Should I treat myself in a parallel way? Should I think of the outputs of my faculties and yours as like the readings of two thermometers the way a third party would? I explore some of the difficulties in answering these questions. If I am to treat myself as well as others as thermometers in this way, it would appear (...) that I cannot reasonably trust my own convictions over yours unless I have antecedent reason to suppose that I am more likely than you to get things right. I appeal to some probabilistic considerations to suggest that our predicament as thermometers might not actually be as bad as it seems. (shrink)
ports the thesis that there exist very many universes. The view has found favor with a number of philosophers such as Derek Parfit ~1998!, J. J. C. Smart ~1989! and Peter van Inwagen ~1993!.1 My purpose is to argue that this is a mistake. First let me set out the issue in more detail.
This is the first comprehensive biography of John Locke to be published in nearly a half century. Setting Locke's life within exciting historical and intellectual contexts, which included the English Civil War, religious persecution, and the Glorious Revolution of 1688, Roger Woolhouse interweaves an account of Locke's life with a summary and development of his ideas in theory of knowledge, philosophy of science, medicine, economics, philosophy of religion, and political philosophy. Systematic and encyclopedic in its coverage, Woolhouse's biography offers (...) both an account and explanation of Locke's ideas, while treating seriously his emotional relationship with Elinor Parry. Based on broad research and many years of study of Locke's philosophy, this volume is an authoritative biography on one of the most significant early modern philosophers. (shrink)
It is notoriously difficult to spell out the norms of inductive reasoning in a neat set of rules. I explore the idea that explanatory considerations are the key to sorting out the good inductive inferences from the bad. After defending the crucial explanatory virtue of stability, I apply this approach to a range of inductive inferences, puzzles, and principles such as the Raven and Grue problems, and the significance of varied data and random sampling.
From Botticelli to birdsong, Mozart, and the Turner Prize, Roger Scruton explores what it means for something to be beautiful. This thought-provoking introduction to the philosophy of beauty draws conclusions that some may find controversial, but, as Scruton shows, help us to find greater sense of meaning in the beautiful objects around us.
This book, sure to become a standard reference work, is a comprehensive, lucid, and systematic commentary on Kant's practical philosophy. Kant is arguably the most important moral philosopher of the modern period. Using as nontechnical a language as possible, Professor Sullivan offers a detailed, authoritative account of Kant's moral philosophy - including his ethical theory, his philosophy of history, his political philosophy, his philosophy of religion, and his philosophy of education - and demonstrates the historical, Kantian origins of such important (...) notions as 'autonomy', 'respect for persons', 'rights', and 'duties'. An invaluable resource, this book will be extremely useful to advanced undergraduates, graduates, and professional philosophers alike. (shrink)
Is God a person, like you and me eventually, but only much better and without our human deficiencies? When you read some of the philosophers of religion, including Richard Swinburne, Alvin Plantinga, or Open Theists, God appears as such a person, in a sense closer to Superman than to the Creator of Heaven and Earth. It is also a theory that a Christian pastoral theology today tends to impose, insisting that God is close to us and attentive to all of (...) us. But this modern account of God could be a deep and even tragic mistake. One God in three persons, the formula of the Trinity, does not mean that God is a person. On this matters we need an effort in the epistemology of theology to examine more precisely what we can pretend to know about God, and especially how we could pretend to know that God is person. (shrink)
Epistemic subjectivism, as I am using the term, is a view in the same spirit as relativism, rooted in skepticism about the objectivity or universality of epistemic norms. I explore some ways that we might motivate subjectivism drawing from some common themes in analytic epistemology. Without diagnosing where the arguments go wrong, I argue that the resulting position is untenable.
This is the most up-to-date, brief and accessible introduction to Kant's ethics available. It approaches the moral theory via the political philosophy, thus allowing the reader to appreciate why Kant argued that the legal structure for any civil society must have a moral basis. This approach also explains why Kant thought that our basic moral norms should serve as laws of conduct for everyone. The volume includes a detailed commentary on Foundations of the Metaphysics of Morals, Kant's most widely studied (...) work of moral philosophy. The book complements the author's much more comprehensive and systematic study Immanuel Kant's Moral Theory, a volume that has received the highest critical praise. With its briefer compass and non-technical style this new introduction should help to disseminate the key elements of one of the great modern philosophies to an even wider readership. (shrink)
Can we justify our most basic beliefs about morality, religion and the nature of the world? Can there be a rational and objective way of choosing between alternative societies, modes of life or world-views? Dr Trigg shows how philosophical analysis is relevant to these questions and criticizes the tendency to emphasize notions of commitment and convention at the expense of truth and reason. He draws parallels between issues that are often too isolated from each other and identifies a cluster of (...) related ideas, all of which stress the notion of self-contained conceptual systems that define their own standards of rationality. First published in 1973, this book will interest professional philosophers as a vigorous and distinctive exposition of several fundamental philosophical problems and more especially it can be used as an introduction for students to a wide range of philosophical problems. (shrink)
In his bestselling work of popular science, Sir Roger Penrose takes us on a fascinating roller-coaster ride through the basic principles of physics, cosmology, mathematics, and philosophy to show that human thinking can never be emulated by a machine.