We attempt to clarify the main conceptual issues in approaches to ‘objectification’ or ‘measurement’ in quantum mechanics which are based on superselection rules. Such approaches venture to derive the emergence of classical ‘reality’ relative to a class of observers; those believing that the classical world exists intrinsically and absolutely are advised against reading this paper. The prototype approach (K. Hepp, Helv. Phys. Acta45 (1972), 237–248) where superselection sectors are assumed in the state space of the apparatus is shown to be (...) untenable. Instead, one should couple system and apparatus to an environment, and postulate superselection rules for the latter. These are motivated by the locality of any observer or other (actual or virtual) monitoring system. In this way ‘environmental’ solutions to the measurement problem (H.D. Zeh, Found. Phys.1 (1970), 69–76; W. H. Zurek, Phys. Rev.D26 (1982), 1862–1880 and Progr. Theor. Phys.89 (1993), 281–312) become consistent and acceptable, too. Points of contact with the modal interpretation are briefly discussed. We propose a minimal value attribution to observables in theories with superselection rules, in which only central observables have properties. In particular, the eigenvector-eigenvalue link is dropped. This is mainly motivated by Ockham's razor. (shrink)

ZusammenfassungFasst man die Ψ‐Funktion in der Quantenmechanik als eine vollständige Beschreibung eines realen Sachverhaltes auf, so ist die Hypothese einer schwer annehm‐baren Fernwirkung impliziert. Fasst man die Ψ‐Funktion aber als eine unvollständige Beschreibung eines realen Sachverhaltes auf, so ist es schwer zu glauben, dass für eine unvollständige Beschreibung strenge Gesetze für die zeitliche Abhängigkeit gelten.‐ A. E.

Since Descartes, epistemology has been based on first person knowledge. We must begin, according to the usual story, with what is most certain: knowledge of our own sensations and thoughts. In one way or another we then progress, if we can, to knowledge of an objective external world. There is then the final, tenuous, step to knowledge of other minds. I shall argue for a total revision of this picture. All propositional thought, whether positive or skeptical, whether of the inner (...) or of the outer, requires possession of the concept of objective truth, and this concept is accessible only to those creatures that are in communication with others. Knowledge of other minds is thus basic to all thought. But such knowledge requires and assumes knowledge of a shared world of objects in a common time and space. Thus the acquisition of knowledge is not based on a progression from the subjective to the objective; it emerges holistically, and is interpersonalfrom the start. (shrink)

In this book the author has collected a number of his important works and added an extensive commentary relating his ideas to those of other prominentnames in the consciousness debate. The view presented here is that of a convinced dualist who challenges in a lively and humorous way the prevailing materialist "doctrines" of many recent works. Also included is a new attempt to explain mind-brain interaction via a quantum process affecting the release of neurotransmitters. John Eccles received a knighthood in (...) 1958 and was awarded the Nobel Prize for Medicine/Physiology in 1963. He has numerous other awards honouring his major contributions to neurophysiology. (shrink)

Presents a guide to the basics of quantum mechanics and measurement.

How do rational minds make contact with the world? The empiricist tradition sees a gap between mind and world, and takes sensory experience, fallible as it is, to provide our only bridge across that gap. In its crudest form, for example, the traditional idea is that our minds consult an inner realm of sensory experience, which provides us with evidence about the nature of external reality. Notoriously, however, it turns out to be far from clear that there is any viable (...) conception of experience which allows it to do the job. The original problem is to show that thought is rationally constrained by external reality. If sensory experience is to provide the solution--in particular, if it is to provide the answer to sceptical challenges--it must therefore meet two criteria. First, it must itself be `receptive'--i.e., appropriately constrained by external reality. Second, it must be the kind of thing that can enter into a logical or rational relationship with belief--it must already be `conceptual,' in other words. In arguing against the idea that anything could serve both roles, Wilfred Sellars termed this conception of experience "the Myth of the Given.". (shrink)

A completely new translation of the works of Descartes is intended to replace the Haldane and Ross edition, first published in 1911. All material from that edition is translated here, with a number of other texts crucial for understanding Cartesian philosophy.

Introductory survey -- Atomic theory and mechanics -- The quantum postulate and the recent development of atomic theory -- The quantum of action and the description of nature -- The atomic theory and the fundamental principles underlying the description of nature.

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.

Department of History and Philosophy of Science. University of Cambridge, Free School Lane, Cambridge CB2 3RH This paper is concerned with the question of whether atomic particles of the same species, i. e. with the same intrinsic state-independent properties of mass, spin, electric charge, etc, violate the Leibnizian Principle of the Identity of Indiscernibles, in the sense that, while there is more than one of them, their state-dependent properties may also all be the same. The answer depends on what exactly (...) the state-dependent properties of atomic particles are taken to be. On the plausible interpretation that these should comprise all monadic and relational properties that can be expressed in terms of physical magnitudes associated with self-adjoint operators that can be defined for the individual particles, then the weakest form of the Principle is shown to be violated for bosons, fermions and higher-order paraparticles, treated in first quantization *Some of the arguments inn this paper appeared in a thesis submited by one of us (S.F.) In partial fulfilment of the requirements for the PhD degree of the University of London, in 1984. entitled 'Identity and ‘Individuality in Classical and Quantum Physics’. (shrink)

Presenting a look at the human mind's capacity while criticizing artificial intelligence, the author makes suggestions about classical and quantum physics and ..

Jaegwon Kim is one of the most preeminent and most influential contributors to the philosophy of mind and metaphysics. This collection of essays presents the core of his work on supervenience and mind with two sets of postscripts especially written for the book. The essays focus on such issues as the nature of causation and events, what dependency relations other than causal relations connect facts and events, the analysis of supervenience, and the mind-body problem. A central problem in the philosophy (...) of mind is the problem of explaining how the mind can causally influence bodily processes. Professor Kim explores this problem in detail, criticizes the nonreductionist solution of it, and offers a modified reductionist solution of his own. Both professional philosophers and their graduate students will find this an invaluable collection. (shrink)

Much as we would like to conceive empirical thought as rationally grounded in experience, pitfalls await anyone who tries to articulate this position, and ...

The aim of the paper is to propose a general conception of holism which is applicable to cases as far apart as holism in belief systems and holism in quantum physics. My proposal characterizes a holistic system S in terms of generic ontological dependence among its parts. This dependence relates to some of the properties that make something a part of an S whenever there is a suitable arrangement with other things. My proposal thus also characterizes what it is for (...) something to be a part of a holistic system and enables us to conceive of holistic properties. (shrink)

One can give a strong sense to the idea that a relation does not 'reduce' to non-relational properties by saying that a relation does not supervene upon the non-relational properties of its relata. That there are such inherent relations I call the doctrine of relational holism, a doctrine which seems to conflict with traditional ideas about physicalism. At least parts of classical physics seem to be free of relational holism, but quantum mechanics, on at least some interpretations, incorporates the doctrine (...) in an all pervasive way. (shrink)

This paper is a response to some recent discussions of many-minds interpretations in the philosophical literature. After an introduction to the many-minds idea, the complexity of quantum states for macroscopic objects is stressed. Then it is proposed that a characterization of the physical structure of observers is a proper goal for physical theory. It is argued that an observer cannot be defined merely by the instantaneous structure of a brain, but that the history of the brain's functioning must also be (...) taken into account. Next the nature of probability in many-minds interpretations is discussed and it is suggested that only discrete probability models are needed. The paper concludes with brief comments on issues of actuality and identity over time. (shrink)

This paper attempts an interpretation of Everett''s relative state formulation of quantum mechanics that avoids the commitment to new metaphysical entities like worlds or minds. Starting from Everett''s quantum mechanical model of an observer, it is argued that an observer''s belief to be in an eigenstate of the measurement (corresponding to the observation of a well-defined measurement outcome) is consistent with the fact that she objectively is in a superposition of such states. Subjective states corresponding to such beliefs are constructed. (...) From an analysis of these subjective states and their dynamics it is argued that Everett''s pure wave mechanics is subjectively consistent with von Neumann''s classical formulation of quantum mechanics. It follows from the argument that the objective state of a system is in principle unobservable. Nevertheless, an adequate concept of empirical reality can be constructed. (shrink)