Online research in philosophy

There are two versions of the putative connection between consciousness and the measurement problem of quantum mechanics : consciousness as the cause of state vector reduction, and state vector reduction as the physical basis of consciousness. In this article, these controversial ideas are neither accepted uncritically, nor rejected from the outset in the name of some prejudice about objective knowledge. Instead, their origin is sought in our most cherished (but disputable) beliefs about the place of mind and consciousness in the world. It is first pointed out that these common beliefs about mind and consciousness arise from reification of situated first-person experience. Then, situatedness is shown to be a constitutive part of any exhaustive treatment of quantum measurements. It turns out that the alleged connection between consciousness and the measurement problem is a symptom of (i) the ineliminability of our being situated from the end-product of science, and (ii) our difficulty to express correctly this being situated.

This paper is about a puzzle which lies at the heart of contemporary physicalist theories of mind. On the one hand, the original motivation for physicalism was the need to explain the place of mental causation in the physical world. On the other hand, physicalists have recently come to see the explanation of mental causation as one of their major problems. But how can this be? I-low can it be that physicalist theories still have a problem explaining something which their physicalism was intended to explain in the first place? lf physicalism is meant to be an explanation of mental causation, then why should it still face the problem of mental causation? Disentagling this puzzle will cast light both on the recent mental causation debate and on physicalism itself. We can make a broad distinction between those forms of physicalism which identify mental and physical items and those which claim that there is some weaker relation of ’constitution’ between the mental and the physical. This latter view is now the orthodox version of physicalism. I shall argue that the problem of mental causation is only a problem for this orthodox physicalism, and not for identity theories. ln itself, this is not a particularly unusual claim. But I shall also argue that the real lesson of the mental causation debate is that orthodox physicalism is either unstable or unmotivated. It is unstable because (unlike the identity theories) it cannot reconcile mental causation with its other physicalist assumptions. It is unmotivated because in attempting to solve this mental causation problem, orthodox physicalism typically abandons one (or more) of the assumptions which form part of the original motivation for physicalism. To establish this, I need to explain (a) the nature of the arguments for physicalism, (b) the problem of mental causation, and (c) the standard solutions to the problem. These three tasks will form the main substance of this paper. But first I need to make some preliminary remarks about physicalism..

Although 'most contemporary analytic philosophers [endorse] a physicalist picture of the world' (A. Newen; V. Hoffmann; M. Esfeld, 'Preface to Mental Causation, Externalism and Self-Knowledge', Erkenntnis , 67 (2007), p. 147), it is unclear what exactly the physicalist thesis states. The response that physicalism is the thesis that everything is physical does not solve the problem but is a precise statement of the problem because 'the claim is hopelessly vague' (G. Hellman; F. Thompson, 'Physicalism: Ontology, Determination, and Reduction', Journal of Philosophy , 72 (1975), p. 552). I argue that physicalism in fact should be the thesis that every existing particular essentially exemplifies properties the exemplification of which does not conceptually entail the existence of conscious beings. Physicalism thus is a purely philosophical thesis with no intrinsic relation to physics. 1.

Abstract: This paper assesses the Everettian approach to the measurement problem, especially the version of that approach advocated by Simon Saunders and David Wallace. I emphasise conceptual, indeed metaphysical, aspects rather than technical ones; but I include an introductory exposition of decoherence. In particular, I discuss whether---as these authors maintain---it is acceptable to have no precise definition of 'branch' (in the Everettian kind of sense). (A version of this paper will appear in a CTNS/Vatican Observatory volume on Quantum Theory and Divine Action, ed. Robert Russell et al.).

This paper investigates the possibiity of developing a fully micro realistic version of elementary quantum mechanics. I argue that it is highly desirable to develop such a version of quantum mechanics, and that the failure of all current versions and interpretations of quantum mechanics to constitute micro realistic theories is at the root of many of the interpretative problems associated with quantum mechanics, in particular the problem of measurement. I put forward a propensity micro realistic version of quantum mechanics, and suggest how it might be possible to discriminate, on expermental grounds, between this theory and other versions of quantum mechanics.

The measurement problem of quantum theory is discussed, and the difficulty of trying to solve it within the confines of a local, Lorentz-invariant physics is emphasised. This leads to the obvious suggestion to seek a solution beyond physics, in particular, by introducing the concept of consciousness. The resulting dualistic model, in the natural form suggested by quantum theory, is shown to differ in several respects from the classical model of Descartes, and to suggest solutions to some of the long-standing problems concerning the relation of consciousness to the physical world.

The literature on physicalism often fails to elucidate, I think, what the word physical in physical ism precisely means. Philosophers speak at times of an ideal set of fundamental physical facts, or they stipulate that physical means non-mental , such that all fundamental physical facts are fundamental facts pertaining to the non-mental. In this article, I will probe physicalism in the very much tangible framework of quantum mechanics. Although this theory, unlike “ideal physics” or some “final theory of non-mentality”, is an incomplete theory of the world, I believe this analysis will be of value, if for nothing else, at least for bringing some taste of physical reality, as it were, back to the debate. First, I will introduce a broad characterization of the physicalist credo. In Sect. 2, I will provide a rather quick review of quantum mechanics and some of its current interpretations. In Sect. 3, the notion of quantum non-separability will be analyzed, which will facilitate a discussion of the wave function ontology in Sect. 4. In Sects. 5 and 6, I will explore competing views on the implications of this ontology. In Sect. 7, I will argue that the prior results, based on a thoroughly realist interpretation of quantum mechanics, support only a weak version of non-reductive physicalism.

The claim of this paper is that we should envisage physicalism as an ontological holism. Our current basic physics, quantum theory, suggests that, ontologically speaking, we have to assume one global quantum state of the world; many of the properties that are often taken to be intrinsic properties of physical systems are in fact relations, which are determined by that global quantum state. The paper elaborates on this conception of physicalism as an ontological holism and considers issues such as supervenience, realization of higher-order properties by basic physical properties, and reduction. Keywords: physicalism, holism, relations, space-time, quantum physics, Humean supervenience.