My work is concerned mainly with an abstract subject: the problem of human knowledge and, in particular, of scientific knowledge.I am an optimist. I am an optimist in a world where among the intelligentsia it has become a strict rule that one must be a pessimist if one wants to be “in”. But I do believe that our age is not so bad as is generally maintained; I do believe that it is better and more beautiful than its reputation. A (...) quarter of a century ago, I gave a lecture, the title of which sounds today even more provocative than it did then: “The History of our Time: An Optimist's View”. (shrink)

We express here the statement » The probability of a given b equals r « symbolically by » p = r «. A formal axiomatic calculus can be constructed comprising all the well‐known laws of probability theory. This calculus can be interpreted in various ways. The present paper is a criticism of the subjective interpretation; that is to say, of any interpretation which assumes that probability expresses degrees of incomplete knowledge: a is the statement incompletely known, b is our total (...) knowledge, and p is the degree to which a is entailed by b. The subjective interpretation has often been proposed as an explanation and even a sharpening of the various objective theories . It is shown in the paper that this proposal cannot be realised because the subjective theory cannot lead to results which are compatible with the objective theory. This is due to various reasons, the most important of which is that the objective theory interprets » b « in » p « as a statement of the objective conditions of an experiment and » a « as one of its possible results. The subjective theory on the other hand interprets » b « as our total relevant knowledge which will in general include some knowledge of previous results of the experiment. It is shown that this must lead to incompatibility owing to the fact that this knowledge of previous results must influence the value of the probability.It is shown, in this way, that any probabilistic theory of the process of learning from experience—that is to say, any probabilistic theory of induction—must lead to contradictions.RésuméL'énoncé: » La probabilité de a, si b est donné, est égale à r « est ici exprimé symboliquement par » p = r «. On peut construire un système axiomatique formel qui contient toutes les règles bien connues du calcul des probabilités. Ce calcul formel peut ětre interprété de manières très différentes. L'article contient une critique des interprétations subjectives, c'est‐à‐dire des interprétations qui admettent que la probabilité exprime des degrés de connaissance incomplète: a est un énoncé qu'on ne connaǐt que partiellement, b est notre connaissance totale, et p exprime le degré auquel a est implicitement contenu dans b. L'interprétation subjective a souvent été proposée comme une explication et un renforcement des différentes théories objectives . Dans cet article, l'auteur montre que ce projet n'est pas réalisable, car la théorie subjective mène à des résultats qui contredisent la théorie objective. Plusieurs circonstances sont responsables de cette situation; la plus importante, c'est que la théorie interprète le » b « dans » p « comme une description des conditions objectives d'une expérience . D'autre part, la théorie subjective interprète » b « comme notre savoir total , et ce savoir inclura en général des informations sur les résultats obtenus antérieurement pour cette expérience. L'auteur montre que ce fait conduit à une contradiction entre les deux interprétations, car cette connaissance doit avoir une influence sur la valeur subjective de la probabilité.A l'aide de ce raisonnement, on peut montrer que la théorie des probabilités appliquée au processus inductif tirant une expérience du domaine expérimental conduit à des contradictions.ZusammenfassungDie Aussage » Die Wahrscheinlichkeit von a, wenn b gegeben ist, ist gleich r « wird hier symbolisch durch » p = r « ausgedrückt. Ein formales Axiomensystem kann konstruiert werden, das alle die wohlbekannten Regeln der Wahrscheinlichkeitsrechnung enthält. Dieser formale Kalkül kann in sehr verschiedener Weise interpretiert werden. Der Artikel enthält eine Kritik der subjektiven Interpretationen; das heisst, jener Interpretationen die annehmen, dass die Wahrscheinlichkeit Grade von unvollständigem Wissen ausdrückt: a ist ein Satz der unvollständig gewusst wird, b ist unser Gesamtwissen, und p drückt den Grad aus zu dem a in b implizit enthalten ist. Die subjektive Interpretation wurde oft als eine Erklärung und Verschärfung der verschiedenen objektiven Theorien vorgeschlagen. In dem Artikel wird gezeigt, dass der Vorschlag undurchführbar ist, da die subjektive Theorie zu Resultaten führt, die der objektiven Theorie widersprechen. Verschiedene Umstände tragen zu dieser Situation bei. Der wichtigste dieser Umstände ist, dass die objektive Theorie das » b « in » p « als eine Beschreibung der objektiven Bedingungen eines Experimentes interpretiert . Andererseits interpretiert die subjektive Theorie » b « als unser Gesamtwissen , und dieses wird im allgemeinen Informationen bezüglich früherer Resultate dieses Experiments einschliessen. Es wird gezeigt, dass das zu einem Widerspruch zwischen den Interpretationen führt, da dieses Wissen Einfluss auf den subjektiven Wahrscheinlichkeitswert haben muss.Mit Hilfe dieses Gedankenganges wird gezeigt, dass die Wahrscheinlichkeitstheorie des induktiven Lernens aus der Erfahrung zu Widersprüchen führt. (shrink)

The burden of this theorem, stated informally, is that when a hypothesis h is maximally independent of the evidence — that is, it goes wholly beyond the evidence —, then the probability p(h, e) increases when the evidence e is weakened; and hence, the weaker is the evidence, the greater is the probabilistic support.

Now in a third edition, Introduction to Philosophy: Classical and Contemporary Readings is a highly acclaimed, topically organized collection that covers five major areas of philosophy--theory of knowledge, philosophy of religion, philosophy of mind, freedom and determinism, and moral philosophy. Editor Louis P. Pojman enhances the text's topical organization by arranging the selections into a pro/con format to help students better understand opposing arguments. He also includes accessible introductions to each chapter, subsection, and individual reading, a unique feature for an (...) anthology of this depth. While the book focuses on a compelling sampling of classical material--including selections from Plato, Aristotle, Descartes, Locke, Berkeley, Hume, and Kant--it also incorporates some of philosophy's best twentieth-century and contemporary work, featuring articles by Bertrand Russell, Richard Taylor, John Searle, Thomas Nagel, and others. This third edition contains an expanded glossary, more extensive section introductions, and twelve new selections: Karl Popper: "Epistemology without a Knowing Subject" Richard Rorty: "Dismantling Truth: Solidarity Versus Objectivity" Daniel Dennett: "Postmodernism and Truth" Bruce Russell: "The Problem of Evil: Too Much Suffering" David Chalmers: "Against Materialism: Can Consciousness Be Reductively Explained?" Baron Paul Henri d'Holbach: "A Defense of Determinism" Michael Levin: "A Compatibilist Defense of Moral Responsibility" Plato: Socratic Morality: "Crito" Herodotus: "Custom Is King" J. L. Mackie: "The Subjectivity of Values" Louis P. Pojman: "A Critique of Mackie's Theory of Moral Subjectivism" Thomas Nagel: "Moral Luck". (shrink)

Kant's critical philosophy marks the end of a two-thousand year tradition of metaphysics. Against this older tradition, Kant proposes a new metaphysics of knowledge and human freedom with the autonomy of the subject as its principle. Led by the principle of subjectivity, it attempts to obtain a unified understanding of the whole world organized into a system of reason. In this way, the idea of classical metaphysics receives a new controversial interpretation still discussed today. In twelve contributions, the fifth volume (...) of the Yearbook pursues the different forms of grounding metaphysics after Kant. (shrink)

The essentialism story is a version of the history of biological classification that was fabricated between 1953 and 1968 by Ernst Mayr, who combined contributions from Arthur Cain and David Hull with his own grudge against Plato. It portrays pre-Darwinian taxonomists as caught in the grip of an ancient philosophy called essentialism, from which they were not released until Charles Darwin's 1859 Origin of Species. Mayr's motive was to promote the Modern Synthesis in opposition to the typology of idealist morphologists; (...) demonizing Plato served this end. Arthur Cain's picture of Linnaeus as a follower of 'Aristotelian' (scholastic) logic was woven into the story, along with David Hull's application of Karl Popper's term, 'essentialism', which Mayr accepted in 1968 as a synonym for what he had called 'typological thinking'. Although Mayr also pointed out the importance of empiricism in the history of taxonomy, the essentialism story still dominates the secondary literature. The history of the first telling of the essentialism story exposes its scant basis in fact. (shrink)

A comprehensive history of how induction has been conceived, from Socrates to Karl Popper.

This is a study in what Naess calls the "new historiography of science," i.e., the view that science is and has been discontinuous, non-accumulative, and somewhat arbitrary. Readers familiar with the controversy between Thomas Kuhn and Karl Popper will undoubtedly note that Naess attempts to achieve a synthesis of their opposed positions. Against Popper, Naess argues there is no standard of rejection and refutation for theories in science that will bear the weight of both the history and (...) present practice of the various disciplines. Instead there are many such standards and herein lies the "pluralistic aspect" of the scientific enterprise. But contrary to Kuhn, irrationalism is not found to be the alternative to a Popperian framework. What is required according to Naess is a broader conception of rationality and decision making than classical philosophers and historians of science were willing to embrace. The outline of such a conception is presented here. Naess also favors encouragement of a methodological pluralistic approach since he finds that the possibilities are almost endless. Nor is the history of science exempt from this invitation. In a final chapter Naess turns his thesis to historiography itself and explores the consequences of pluralism and possibilism in this field.—R.P.M. (shrink)

This paper criticises a line of argument adopted by peter winch, Karl popper, And others, To the effect that the course of human history cannot be predicted. On this view it is impossible to predict in a particularly detailed way certain events ('original acts') on which important social developments depend. We analyze the argument, Showing that one version fails: original acts are in principle predictable in the relevant way. A cogent version is presented; this requires a special definition (...) for 'original act'. But, We claim, Social developments do not depend on original acts so defined. We argue separately for the possibility of a person, Or a scientific community, Predicting his or its own original acts. (shrink)

According to Steinberger, many, defending Hegel against Karl Popper and other critics, have reinterpreted Hegel as an "accommodationist," solving the apparent contradiction between individual and society by a modification of each polis--thus approximating something like liberalism. Steinberger maintains, however, that Hegel was more precisely a "perfectionist," following in a tradition which includes Rousseau and Marx, engaged in the enterprise of dissolving the discrepancy between the individual and society, and confident that in some way the "Rose" of reason might (...) be found in the "Cross" of the present. (shrink)

This classic remains one of Karl Popper's most wide-ranging and popular works, notable not only for its acute insight into the way scientific knowledge grows, but also for applying those insights to politics and to history.

The survival and development of consciousness in biological evolution call for an explanation. An interactionistic mind-brain theory seems to have the greatest explanatory value in this context. An interpretation of an interactionistic hypothesis, recently proposed by Karl Popper, is discussed both theoretically and based on recent experimental data. In the interpretation, the distinction between the conscious mind and the brain is seen as a division into what is subjective and what is objective, and not as an ontological distinction (...) between something immaterial and something material. The interactionistic hypothesis is based on similarities between minds and physical forces. The conscious mind is understood to interact with randomly spontaneous spatio-temporal patterns of action potentials through an electromagnetic field. Consequences and suggestions for future studies are discussed. (shrink)