Noncontextual hidden variables theories, assigning simultaneous values to all quantum mechanical observables, are inconsistent by theorems of Gleason and others. These theorems do not exclude contextual hidden variables theories, in which a complete state assigns values to physical quantities only relative to contexts. However, any contextual theory obeying a certain factorisability conditions implies one of Bell's Inequalities, thereby precluding complete agreement with quantum mechanical predictions. The present paper distinguishes two kinds of contextual theories, ‘algebraic’ and ‘environmental’, and investigates when factorisability (...) is reasonable. Some statements by Fine about the philosophical significance of Bell's Inequalities are then assessed. (shrink)

When Laszlo Tisza first came to MIT in 1941, he had already made significant contributions to physics. In the years since, he has consolidated his position as one of the most important theoreticians of his time. Tisza's major areas of activity, closely reflected in these twenty-three essays, have included studies of quantum liquids (in particular, the remarkable properties of liquid helium and the nature of superfluidity and superconductivity), irreversible thermodynamics and the statistical thermodynamics of equilibrium, phase transitions and critical phenomena, (...) and the application of group theory to molecular spectroscopy. Tisza has also given long and close attention to the philosophy and history of his science, to a degree rarely attained by an active research physicist. His special contribution has been his insights into the logical and conceptual structure of physics. This aspect of Tisza's work is less well known than his technical contributions, and the book has been structured to right the balance by revealing Tisza the natural philosopher who collaborates with Tisza the physicist. Written by Tisza's colleagues and former students, the essays are grouped under five headings: Foundations of Probability and Thermodynamics; Condensed Matter Physics; Quantum Mechanics and Relativity; Biological Systems; and History and Philosophy of Science. Abner Shimony, Professor of Philosophy and Physics at Boston University, has contributed a closing evaluation of Tisza's philosophy of science, and Herman Feshbach, Head of the Department of Physics at MIT, has contributed an opening recollection of Tisza's scientific style. (shrink)

Abner Shimony an eminent philosopher of science, whose work has exerted a profound influence in both the philosophy and physics communities. This two-volume collection of his essays written over a period of forty years explores the interrelations between science and philosophy. Shimony regards the knowing subject as an entity in nature whose faculties must be studied from the points of view of evolutionary biology and empirical psychology. He maintains that the twentieth century is one of the great ages of (...) metaphysics, given the deep implications of quantum mechanics, relativity theory, and molecular biology. The first volume, Scientific Method and Epistemology, deals with the dialectic of subject and object, epistemic probability, induction and scientific theories, perception and conception, and fact and values. The focus of the second volume, Natural Sciences and Metaphysics, is on quantum mechanical measurement and non-locality, parts and wholes, time, and mind and matter. (shrink)

The Society for the Advancement of the Scientific World Conception has done me a great honor by inviting me to be the Sixth Vienna Circle Lecturer. The invitation has also stirred some deep emotions. A central figure of the Vienna Circle, Rudolf Carnap, was my revered teacher of philosophy at the University of Chicago in 1948–9 and later an informal adviser when I wrote a doctoral thesis at Yale University on inductive logic, and he was a friend during those years (...) and thereafter. I was not a disciple, but Carnap did not demand discipleship as a condition for admission to his seminars or to his friendship. He seemed to be baffled by the fact that despite my interest in mathematical logic and theoretical physics I proclaimed myself a metaphysicician and had even published an article in the first issue of The Review of Metaphysics. Carnap formulated a “principle of tolerance” as a philosophical maxim concerning rules of language, but he practiced a human and highly moral version of the principle of tolerance in his profoundly liberal social commitments and in his relations with his students. If he were here tonight, I would wish for his tolerance of the lapses of rigor and the flights of speculation to which he would be exposed. (shrink)

From the very beginning it was realised that quantum physics involves radically new interpretative and epistemological consequences. While hitherto there has been no satisfactory philosophical analysis of these consequences, recent years have witnessed the accomplishment of many experiments to test the foundations of quantum physics, opening up vistas to a completely novel technology: quantum technology. The contributions in the present volume review the interpretative situation, analyze recent fundamental experiments, and discuss the implications of possible future technological applications. Readership: Analytic philosophers (...) (logical empiricists), scientists (especially physicists), historians of logic, mathematics and physics, philosophers of science, and advanced students and researchers in these fields. Can be used for seminars on theoretical and experimental physics and philosophy of science, and as supplementary reading at advanced undergraduate and graduate levels. (shrink)

Professor Savage has been candid and generous in stating his interest in philosophy, and the philosophers who have heard him are surely grateful for this. His attitude is very far from that of some competent scientists and mathematicans who purport to clear up the questions which philosophers raise concerning their disciplines by means of a battery of technical results of varying relevance—a procedure which can often be appropriately described as “an abominable snow-job.” However, Professor Savage's generosity places a responsibility on (...) philosophers, since the questions he raises are difficult. (shrink)

The idea of ensembles which are both pre- and post-selected was introduced by Aharonov, Bergmann, and Lebowitz and developed by Aharonov and his school. To derive formulae for the probabilities of outcomes of a measurement performed on such an ensemble at a time intermediate between pre-selection and post-selection, the latter group introduces a two-vector formulation of quantum mechanics, one vector propagating in the forward direction in time and one in the backward direction. The formulae which they obtain by this radical (...) generalization are vindicated by a rigorous derivation using Bayes’s theorem together with standard quantum mechanical predictions regarding ensembles that are only pre-selected. Their own two-vector derivation, however, suffers from a serious lacuna. (shrink)

H.P. Stapp has proposed a number of demonstrations of a Bell-type theorem which dispensed with an assumption of hidden variables, but relied only upon locality together with an assumption that experimenters can choose freely which of several incompatible observables to measure. In recent papers his strategy has centered upon counterfactual conditionals. Stapp’s paper in American Journal of Physics, 2004, replies to objections raised against earlier expositions of this strategy and proposes a simplified demonstration. The new demonstration is criticized, several subtleties (...) in the logic of counterfactuals are pointed out, and the proofs of J.S. Bell and his followers are advocated. (shrink)

We investigate the thesis of Aharonov, Bergmann, and Lebowitz that time-symmetry holds in ensembles defined by both an initial and a final condition, called preand postselected ensembles. We distinguish two senses of time symmetry and show that the first one, concerning forward directed and time reversed measurements, holds if the measurement process is ideal, but fails if the measurement process is non-ideal, i.e., violates Lüders's rule. The second kind of time symmetry, concerning the interchange of initial and final conditions, fails (...) even in the case of ideal measurements. Bayes's theorem is used as a primary tool for calculating the relevant probabilities. We are critical of the concept that a pair of vectors in Hilbert space, characterizing the initial and final conditions, can be considered to constitute a generalized quantum state. (shrink)

The assumption that the dead past cannot influence the present or future is even more obvious in an argument against causation given by Collingwood in his Essay on Metaphysics.

Criticisms are presented against Eger's challenge to the demarcation between the natural sciences and ethics. Arguments are given both against his endorsement of the “new” philosophy of science and against his rejection of the fact‐value dichotomy. However, his educational recommendations are reinforced rather than weakened by these criticisms.

A combination of methodological considerations and propositions about the causal structure of spacetime provides a reply to Fine's criticisms of the "factorizability requirement" used in several versions of Bell's theorem. His proposal of "action in harmony" is criticized. Experimental tests are proposed for both the "synchronization models" and the "prism models", which Fine has invented as loopholes to Bell's theorem. A theorem of Suppes and Zanotti which purports to show the impossibility of hidden variables is criticized. One of their crucial (...) premisses seems to be justifiable only if one accepts a Parmenidean metaphysics. (shrink)

Table of Contents: Acknowledgements; Preface; 1. Integral epistemology; 2. Reality, causality and closing the circle; 3. Search for a world view that can accommodate our knowledge of microphysics; 4. Perception from an evolutionary point of view; 5. Is observation theory-laden? A problem in naturalistic epistemology; 6. Coherence and the axioms of confirmation; 7. An adamite derivation of the principles of the calculus of probability; 8. The status of the principle of maximum entropy; 9. Scientific inference; 10. Reconsiderations on inductive logic; (...) 11. Comments on two epistemological these of Thomas Kuhn; 12. Comment on Martin Eger's A Tale of Two Controversies; Index. (shrink)

Many of the pioneers of quantum mechanics — notably Planck, Einstein, Bohr, de Broglie, Heisenberg, Schrodinger, Born, Jordan, Lande, Wigner, and London — were seriously concerned with philosophical questions. In each case one can ask a question of psychological and historical interest: was it a philosophical penchant which drew the investigator towards a kind of physics research which is linked to philosophy, or was it rather that the conceptual difficulties of fundamental physics pulled him willy-nilly into the labyrinth of philosophy? (...) I shall not undertake to discuss this question, but shall cite an opinion of Peter Bergmann, which I find congenial: he learned from Einstein that “the theoretical physicist is a philosopher in workingman’s clothes” ([1],q.v). (shrink)

2. "The first four chapters of this book are devoted to explaining the parts played by mathematical reasoning and by theoretical concepts and 'models' in the organization of a scientific theory". In short, this part of Scientific Explanation attempts to show how a modern empiricist can recognize the role of reason in science. The main theses in these chapters are as follows.

I am grateful for the opportunity to share with you some of my convictions, anxieties, and hopes. My central conviction is the immense value of a mental outlook which can be called by the suggestive and historically recognized name Enlightenment, whose exact characterization, however, requires careful discussion. It is an outlook widely shared, though with innumerable personal variations, by the members of the Philosophy of Science Association, by the broader community of scientists, science teachers, and philosophers, and by an ill-defined (...) part of the general public. My anxieties are that the cultivation and the influence of this mental outlook in our nation and in the world are threatened in various ways, among them ideological attacks, slackening of educational standards, and demoralization of its adherents. My central hope is that Enlightenment will prevail despite these threats. (shrink)

The theory of natural selection is a rich systematization of biological knowledge without a first principle. When formulations of a proposed principle of natural selection are examined carefully, each is seen to be exhaustively analyzable into a proposition about sources of fitness and a proposition about consequences of fitness. But whenever the fitness of an organic variety is well defined in a given biological situation, its sources are local contingencies together with the background of laws from disciplines other than the (...) theory of natural selection; and the consequences of fitness for the long range fate of organic varieties are essentially applications of probability theory. Hence there is no role and no need for a principle of the theory of natural selection, and any generalities that may hold in that theory are derivative rather than fundamental. (shrink)

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in (...) the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant. (shrink)

If quantum mechanics is interpreted as an objective, complete, physical theory, applying to macroscopic as well as microscopic systems, then the linearity of quantum dynamics gives rise to the measurement problem and related problems, which cannot be solved without modifying the dynamics. Eight desiderata are proposed for a reasonable modified theory. They favor a stochastic modification rather than a deterministic non-linear one, but the spontaneous localization theories of Ghirardi et al. and Pearle are criticized. The intermittent fluorescence of a trapped (...) atom irradiated by two laser beams suggests a stochastic theory in which the locus of stochasticity is interaction between a material system and the electromagnetic vacuum. (shrink)

An extremum principle was postulated by Horne, Finkelstein, Shull, Zeilinger, and Bernstein in order to derive the physically allowable parameters for sinusoidal standing waves governing a neutron in a crystal which is immersed in a strong external magnetic field: “the expectation value of the total potential 〈V〉 is an extremum.” We show that this extremum principle can be obtained from the variational principle used by Schrodinger to derive his nonrelativistic wave equation. We rederive the solutions found by the above-mentioned authors (...) as well as some additional solutions. (shrink)

A corollary of Gleason's theorem asserts that if the lattice of propositions of a physical system is isomorphic to the lattice of subspaces of a Hilbert space of dimension greater than two, then there is no probability measure that assigns only the values 1 and 0 (truth and falsity, respectively) to each of the propositions. Belinfante outlined an elegant geometrical proof of this corollary but relied upon an unrigorous measure-theoretical statement. An amplified geometrical proof is given along Belinfante's lines, but (...) dispensing with measure theory. (shrink)