This is a new volume of original essays on the metaphysics of quantum mechanics. The essays address questions such as: What fundamental metaphysics is best motivated by quantum mechanics? What is the ontological status of the wave function? What is the nature of the fundamental space (or space-time manifold) of quantum mechanics?

This is a new volume of original essays on the metaphysics of quantum mechanics. The essays address questions such as: What fundamental metaphysics is best motivated by quantum mechanics? What is the ontological status of the wave function? Does quantum mechanics support the existence of any other fundamental entities, e.g. particles? What is the nature of the fundamental space of quantum mechanics? What is the relationship between the fundamental ontology of quantum mechanics and ordinary, macroscopic objects like tables, chairs, and (...) persons? This collection includes a comprehensive introduction with a history of quantum mechanics and the debate over its metaphysical interpretation focusing especially on the main realist alternatives. (shrink)

Realists wanting to capture the facts of quantum entanglement in a metaphysical interpretation find themselves faced with several options: to grant some species of fundamental nonseparability, adopt holism, or to view localized spacetime systems as ultimately reducible to a higher-dimensional entity, the quantum state or wave function. Those adopting the latter approach and hoping to view the macroscopic world as grounded in the quantum wave function face the macro-object problem. The challenge is to articulate the metaphysical relation obtaining between three-dimensional (...) macro-objects and the wave function so that the latter may be seen in some sense as constituting the former. This paper distinguishes several strategies for doing so and defends one based on a notion of partial instantiation. (shrink)

There are now several, realist versions of quantum mechanics on offer. On their most straightforward, ontological interpretation, these theories require the existence of an object, the wavefunction, which inhabits an extremely high-dimensional space known as configuration space. This raises the question of how the ordinary three-dimensional space of our acquaintance fits into the ontology of quantum mechanics. Recently, two strategies to address this question have emerged. First, Tim Maudlin, Valia Allori, and her collaborators argue that what I have just called (...) the ‘most straightforward’ interpretation of quantum mechanics is not the correct one. Rather, the correct interpretation of realist quantum mechanics has it describing the world as containing objects that inhabit the ordinary three-dimensional space of our manifest image. By contrast, David Albert and Barry Loewer maintain the straightforward, wavefunction ontology of quantum mechanics, but attempt to show how ordinary, three-dimensional space may in a sense be contained within the high-dimensional configuration space the wavefunction inhabits. This paper critically examines these attempts to locate the ordinary, three-dimensional space of our manifest image “within” the ontology of quantum mechanics. I argue that we can recover most of our manifest image, even if we cannot recover our familiar three-dimensional space. (shrink)

This paper defends wave function realism against the charge that the view is empirically incoherent because our evidence for quantum theory involves facts about objects in three-dimensional space or space-time . It also criticizes previous attempts to defend wave function realism against this charge by claiming that the wave function is capable of grounding local beables as elements of a derivative ontology.

Some philosophers argue that many contemporary debates in metaphysics are “illegitimate,” “shallow,” or “trivial,” and that “contemporary analytic metaphysics, a professional activity engaged in by some extremely intelligent and morally serious people, fails to qualify as part of the enlightened pursuit of objective truth, and should be discontinued” (Ladyman and Ross, Every thing must go: Metaphysics naturalized , 2007 ). Many of these critics are explicit about their sympathies with Rudolf Carnap and his circle, calling themselves ‘neo-positivists’ or ‘neo-Carnapians.’ Yet (...) despite the fact that one of the main conclusions of logical positivism was that metaphysical statements are meaningless, many of these neo-positivists are themselves engaged in metaphysical projects. This paper aims to clarify how we may see a neo-positivist metaphysics as proceeding in good faith, one that starts with serious engagement with the findings of science, particularly fundamental physics, but also has room for traditional, armchair methods. (shrink)

This article discusses recent disagreements over the correct formulation of physicalism. Although there appears to be a consensus outside those who discuss the issue that physicalists believe that what exists is what is countenanced by physics, as we will see, this orthodoxy faces an important puzzle now frequently referred to as 'Hempel's Dilemma'. After surveying the historical trajectory from Enlightenment-era materialism to contemporary physicalism, I examine several mainstream approaches that respond to Hempel's dilemma, and the benefits and drawbacks of each.

It is widely noted that physicalism, taken as the doctrine that the world contains just what physics says it contains, faces a dilemma which, some like Tim Crane and D.H. Mellor have argued, shows that “physicalism is the wrong answer to an essentially trivial question”. I argue that both problematic horns of this dilemma drop out if one takes physicalism not to be a doctrine of the kind that might be true, false, or trivial, but instead an attitude or oath (...) one takes to formulate one’s ontology solely according to the current posits of physics. (shrink)

Within the field of quantum gravity, there is an influential research program developing the connection between quantum entanglement and spatiotemporal distance. Quantum information theory gives us highly refined tools for quantifying quantum entanglement such as the entanglement entropy. Through a series of well-confirmed results, it has been shown how these facts about the entanglement entropy of component systems may be connected to facts about spatiotemporal distance. Physicists are seeing these results as yielding promising methods for better understanding the emergence of (...) (the dynamical) spacetime (of general relativity) from more fundamental quantum theories, and moreover, as promising for the development of a nonperturbative theory of quantum gravity. However, to what extent does the case for the entanglement entropy-distance link provide evidence that spacetime structure is nonfundamental and emergent from nongravitational degrees of freedom? I will show that a closer look at the results lends support only to a weaker conclusion, that the facts about quantum entanglement are constrained by facts about spatiotemporal distance, and not that they are the basis from which facts about spatiotemporal distance emerge. (shrink)

Physicalism is sometimes portrayed by its critics as a dogma, but there is an empirical argument for the position, one based on the accumulation of diverse microphysical causal explanations in physics, chemistry, and physiology. The canonical statement of this argument was presented in 2001 by David Papineau. The goal of this paper is to demonstrate a tension that arises between this way of understanding the empirical case for physicalism and a view that is becoming practically a received position in philosophy (...) of physics: that microphysics does not support the existence of causal facts (and so does not support causal explanations). Indeed this is a conclusion embraced in recent work by Papineau himself. This paper examines a range of natural ways of avoiding this tension and reconciling the empirical case for physicalism with the rejection of microphysical causation. (shrink)

This paper examines the relationship between physical theories of causation and theories of difference-making. It is plausible to think that such theories are compatible with one another as they are aimed at different targets: the former, an empirical account of actual causal relations; the latter, an account that will capture the truth of most of our ordinary causal claims. The question then becomes: what is the relationship between physical causation and difference-making? Is one kind of causal fact more fundamental than (...) the other? This paper defends causal foundationalism: the view that facts about difference-making are dependent on the obtaining of facts about physical causation. However, the paper's main goal is to clarify the structure of the debate. At the end of the paper, it is shown how settling the issue about the relationship between physical theories of causation and theories of difference-making has more than mere intrinsic interest in unifying the very different pursuits that have been undertaken in the philosophy of causation. It can help to break a stalemate that has arisen in the current debate about mental causation. (shrink)

Metaphysics: An Introduction combines comprehensive coverage of the core elements of metaphysics with contemporary and lively debates within the subject. It provides a rigorous and yet accessible overview of a rich array of topics , connecting the abstract nature of metaphysics with the real world. Topics covered include: Basic logic for metaphysics An introduction to ontologyobjects Material objects Critiques of metaphysics Free Will Time Modality Persistence Causation Social ontology: the metaphysics of race This outstanding book not only equips the reader (...) with a thorough knowledge of the fundamentals of metaphysics but provides a valuable guide to contemporary metaphysics and metaphysicians. Additional features such as exercises, annotated further reading, a glossary and a companion website www.routledge.com/cw/ney will help students find their way around this subject and assist teachers in the classroom. (shrink)

*A shortened version of this paper will appear in Current Controversies in Philosophy of Science, Dasgupta and Weslake, eds. Routledge.* This paper describes the case that can be made for a high-dimensional ontology in quantum mechanics based on the virtues of avoiding both nonseparability and non locality.

Highly idealized models, such as the Hawk-Dove game, are pervasive in biological theorizing. We argue that the process and motivation that leads to the introduction of various idealizations into these models is not adequately captured by Michael Weisberg’s taxonomy of three kinds of idealization. Consequently, a fourth kind of idealization is required, which we call hypothetical pattern idealization. This kind of idealization is used to construct models that aim to be explanatory but do not aim to be explanations.

Jaegwon Kim has argued that unless mental events are reducible to subvening physical events, they are at best overdeterminers of their effects. Recently, nonreductive physicalists have endorsed this consequence claiming that the relationship between mental events and their physical bases is tight enough to render any such overdetermination nonredundant, and hence benign. I focus on instances of this strategy that appeal to the notion of constitution. Ultimately, I argue that there is no way to understand the relationship between irreducible mental (...) events and their physical bases such as to both eliminate causal redundancy and preserve the efficacy of mental events. (shrink)

that the properties of science are purely extrinsic with the metaphysical principle that substances must also have intrinsic properties, the arguments reach the conclusion that there are intrinsic properties of whose natures we cannot know. It is the goal of this paper to establish that such arguments are not just ironic but extremely problematic. The optimistic physicalist principles that help get the argument off the ground ultimately undermine any justification the premises give for acceptance of the conclusion. Though I do (...) find these arguments unsound, it is nevertheless worthwhile to consider them in order to see more clearly what should be the methodology of the philosopher inclined to take the discoveries of physical science as having ontological authority. And, I hope, what follows will prompt the physicalist to ask herself – what room _is_ there for metaphysics once physical science is complete? (shrink)

Configuration space representations have utility in physics but are not generally taken to have ontological significance. We examine one salient reason to think configuration space representations fail to be relevant in determining the fundamental ontology of a physical theory. This is based on a claim due to several authors that fundamental theories must have primitive ontologies. This claim would,if correct, have broad ramifications for how to read metaphysics from physical theory. We survey ways of understanding the argument for a primitive (...) ontology in order to assess the case against configuration space realism. (shrink)

According to phenomenal functionalism, whether some object or event has a given property is determined by the kinds of sensory experiences such objects or events typically cause in normal perceivers in normal viewing conditions. This paper challenges this position and, more specifically, David Chalmers’s use of it in arguing for what he calls virtual realism.

What justifies the allocation of funding to research in physics when many would argue research in the life and social sciences may have more immediate impact in transforming our world for the better? Many of the justifications for such spending depend on the claim that physics enjoys a kind of special status vis-a-vis the other sciences, that physics or at least some branches of physics exhibit a form of fundamentality. The goal of this paper is to articulate a conception of (...) fundamentality that can support such justifications. I argue that traditional conceptions of fundamentality in terms of dynamical or ontic completeness rest on mistaken assumptions about the nature and scope of physical explanations. (shrink)

Reductionists are those who take one theory or phenomenon to be reducible to some other theory or phenomenon. For example, a reductionist regarding mathematics might take any given mathematical theory to be reducible to logic or set theory. Or, a reductionist about biological entities like cells might take such entities to be reducible to collections of physico-chemical entities like atoms and molecules. The type of reductionism that is currently of most interest in metaphysics and philosophy of mind involves the claim (...) that all sciences are reducible to physics. This is usually taken to entail that all phenomena (including mental phenomena like consciousness) are identical to physical phenomena. The bulk of this article will discuss this latter understanding of reductionism. (shrink)

There is a standard way of interpreting physicalism. This is as a completeness thesis of some kind. Completeness physicalists believe there is or in principle could be some future physics that provides a complete explanatory or ontological basis for our universe. And this provides a sense in which physics is special among the sciences, the sense in which it is fundamental. This paper contrasts this standard completeness physicalism with what is a more plausible maximality physicalism. Maximality physicalists believe physics is (...) special only in its providing an epistemic framework that is ontologically or explanatorily superior in some respect. This paper shows how completeness physicalists cannot, while maximality physicalists can, provide an adequate explanation of the empirical support for and the pragmatic usefulness of physicalism. It also shows how maximality physicalism is better supported in light of several developments from late twentieth century philosophy of science. (shrink)

Philosophy and Phenomenological Research, EarlyView.