According to one prominent view, current metaphysics is hopelessly disconnected from the implications of modern science and as a result should be abandoned fort.

According to one prominent view, current metaphysics is hopelessly disconnected from the implications of modern science and as a result should be abandoned forthwith (Ladyman and Ross 2007). Others have taken a more conciliatory stance, suggesting that the metaphysicians’ toolbox may yet yield devices that could prove useful to the philosopher of science (French and McKenzie 2012). In this book, Sider aims to contribute to the metaphysics of science by setting out an array of such tools and indicating which are (...) up to the job. More particularly, he wants to demonstrate the usefulness of certain ‘postmodal’ concepts, such as fundamentality, which is a promising tack, given that (Callender 2011), for example, has argued that it was the modal turn initiated by the likes of Kripke that is ultimately responsible for the disconnect. To illustrate his overall claim that the tools we deploy may help frame the issues that we take to be central to the metaphysics of science, Sider chooses to analyse various forms of structuralism, the view that we should take structure to be primary and the relevant entities to be secondary : nomic essentialism, which takes properties to be ‘bound up’ with laws (ibid., p. 23); structural realism, which holds, in its epistemic form, that all that we know about the world is its structure and, in the ontic alternative, that the world is, in some sense, structure; and comparativism about quantities, whereby quantities are ascribed to objects comparatively or relationally (ibid., p. 122). His conclusions are that no postmodal sense can be made of the first two, and so much the worse for them, whereas comparativism about quantities can unproblematically be stated in such terms (ibid., p. 119), and indeed, when it comes to ‘fundamentality’, at least, may well be this concept’s ‘Waterloo’ (ibid., p. 166). The worry some philosophers of science will have is that Sider’s arguments are driven more by his metaphysics than the relevant science and the issues that he identifies don’t quite map onto those they take to be central. (shrink)

According to ‘Ontic Structural Realism’ (OSR), physical objects—qua metaphysical entities—should be reconceptualised, or, more strongly, eliminated in favour of the relevant structures. In this paper I shall attempt to articulate the relationship between these putative objects and structures in terms of certain accounts of metaphysical dependence currently available. This will allow me to articulate the differences between the different forms of OSR and to argue in favour of the ‘eliminativist’ version. A useful context is provided by Floridi’s account of the (...) relationship between ‘ontic’ and ‘epistemic’ structural realisms and I shall conclude with some brief remarks on possible extensions of OSR into other scientific domains. (shrink)

According to 'Ontic Structural Realism' (OSR), physical objects—qua metaphysical entities—should be reconceptualised, or, more strongly, eliminated in favour of the relevant structures. In this paper I shall attempt to articulate the relationship between these putative objects and structures in terms of certain accounts of metaphysical dependence currently available. This will allow me to articulate the differences between the different forms of OSR and to argue in favour of the 'eliminativist' version. A useful context is provided by Floridi's account of the (...) relationship between 'ontic' and 'epistemic' structural realisms and I shall conclude with some brief remarks on possible extensions of OSR into other scientific domains. (shrink)

Quasi-set theory has been proposed as a means of handling collections of indiscernible objects. Although the most direct application of the theory is quantum physics, it can be seen per se as a non-classical logic (a non-reflexive logic). In this paper we revise and correct some aspects of quasi-set theory as presented in [12], so as to avoid some misunderstandings and possible misinterpretations about the results achieved by the theory. Some further ideas with regard to quantum field theory are also (...) advanced in this paper. (shrink)

Various forms of underdetermination that might threaten the realist stance are examined. That which holds between different 'formulations' of a theory (such as the Hamiltonian and Lagrangian formulations of classical mechanics) is considered in some detail, as is the 'metaphysical' underdetermination invoked to support 'ontic structural realism'. The problematic roles of heuristic fruitfulness and surplus structure in attempts to break these forms of underdetermination are discussed and an approach emphasizing the relevant structural commonalities is defended.

In the philosophy of science, identity over time emerges as a central concern both as an ontological category in the interpretation of physical theories, and as an epistemological problem concerning the conditions of possibility of knowledge. In Reichenbach and subsequent writers on the problem of indistinguishable quantum particles we see the return of a contrast between Leibniz and Aquinas on the subject of individuation. The possibility of rejecting the principle of the identity of indiscernibles has certain logical difficulties, leading us (...) inexorably from ontology into epistemology. For the epistemological problem we attend to the differences that emerged between the (neo-)Kantian and logical empiricist traditions, also saliently displayed in Reichenbach's writings. After examining the contrast between Kant's and Leibniz's conceptions of empirical knowledge, specifically with respect to the irreducibility of spatiotemporal determinations, we explore an application of a neo-Kantian view to the same problem of indistinguishable quantum particles. (shrink)

This paper argues that ontic structural realism (OSR) faces a dilemma: either it remains on the general level of realism with respect to the structure of a given theory, but then it is, like epistemic structural realism, only a partial realism; or it is a complete realism, but then it has to answer the question how the structure of a given theory is implemented, instantiated or realized and thus has to argue for a particular interpretation of the theory in question. (...) This claim is illustrated by examining how OSR fares with respect to the three main candidates for an ontology of quantum mechanics, namely many worlds-type interpretations, collapse-type interpretations and hidden variable-type interpretations. The result is that OSR as such is not sufficient to answer the question of what the world is like if quantum mechanics is correct. (shrink)

This paper seeks to answer the following question: What is a minimal set of entities that form an ontology of the natural world, given our well-established physical theories? The proposal is that the following two axioms are sufficient to obtain such a minimalist ontology: There are distance relations that individuate simple objects, namely matter points. The matter points are permanent, with the distances between them changing. I sketch out how one can obtain our well-established physical theories on the basis of (...) just these two axioms. The argument for minimalism in ontology then is that it yields all the explanations that one can reasonably demand in science and philosophy, while avoiding the drawbacks that come with a richer ontology. (shrink)

This paper seeks to answer the following question: What is a minimal set of entities that form an ontology of the natural world, given our well-established physical theories? The proposal is that the following two axioms are sufficient to obtain such a minimalist ontology: (1) There are distance relations that individuate simple objects, namely matter points. (2) The matter points are permanent, with the distances between them changing. I sketch out how one can obtain our well-established physical theories on the (...) basis of just these two axioms. The argument for minimalism in ontology then is that it yields all the explanations that one can reasonably demand in science and philosophy, while avoiding the drawbacks that come with a richer ontology. (shrink)

Cet article se propose de reprendre les discussions autour du principe d’identité des indiscernables (PIdI) en précisant le type d’entités qui pourraient y déroger. J’y défends l’idée que le rejet du PIdI ressortit à la possibilité de trois types de doubles : les répliques pures, ou reproductions parfaites, les doubles purs, doubles qui ne peuvent pas même être distingués par des relations spatio-temporelles, et enfin les coïncidents purs qui sont des doubles « superposés ». La thèse que je défends consiste (...) à montrer que l’existence de telles entités est non seulement concevable, mais même, pour les deux premières sortes, physiquement possible. Pour ce qui concerne la possibilité des coïncidents purs, le rejet de telles entités peut être appuyé indépendamment du PIdI sur un principe de parcimonie ontologique basé sur une indifférence causale. (shrink)

This paper offers a critical assessment of the current state of the debate about the identity and individuality of material objects. Its main aim, in particular, is to show that, in a sense to be carefully specified, the opposition between the Leibnizian ‘reductionist’ tradition, based on discernibility, and the sort of ‘primitivism’ that denies that facts of identity and individuality must be analysable has become outdated. In particular, it is argued that—contrary to a widespread consensus—‘naturalised’ metaphysics supports both the acceptability (...) of non-qualitatively grounded (both ‘contextual’ and intrinsic) identity and a pluralistic approach to individuality and individuation. A case study is offered that focuses on non-relativistic quantum mechanics, in the context of which primitivism about identity and individuality, rather than being regarded as unscientific, is on the contrary suggested to be preferable to the complicated forms of reductionism that have recently been proposed. More generally, by assuming a plausible form of anti-reductionism about scientific theories and domains, it is claimed that science can be regarded as compatible with, or even as suggesting, the existence of a series of equally plausible grades of individuality. The kind of individuality that prevails in a certain context and at a given level can be ascertained only on the basis of the specific scientific theory at hand. (shrink)

Saunders has recently claimed that “identical quantum particles” with an anti-symmetric state (fermions) are weakly discernible objects, just like irreflexively related ordinary objects in situations with perfect symmetry (Black’s spheres, for example). Weakly discernible objects have all their qualitative properties in common but nevertheless differ from each other by virtue of (a generalized version of) Leibniz’s principle, since they stand in relations an entity cannot have to itself. This notion of weak discernibility has been criticized as question begging, but we (...) defend and accept it for classical cases likes Black’s spheres. We argue, however, that the quantum mechanical case is different. Here the application of the notion of weak discernibility indeed is question begging and in conflict with standard interpretational ideas. We conclude that the introduction of the conceptual resource of weak discernibility does not change the interpretational status quo in quantum mechanics. (shrink)

According to classical physics particles are basic building blocks of the world. These classical particles are distinguishable objects, individuated by unique combinations of physical properties. By contrast, in quantum mechanics the received view is that particles of the same kind are physically indistinguishable from each other and lack identity. This doctrine rests on the quantum mechanical symmetrization postulates together with the “factorist” assumption that each single particle is represented in exactly one factor space of the tensor product Hilbert space of (...) a many-particle system. Even though standard in theoretical physics and the philosophy of physics, the assumption of factorism and the ensuing indistinguishability of particles are problematic. Particle indistinguishability is irreconcilable with the everyday meaning of “particle”, and also with how this term is used in the practice of physics. Moreover, it is a consequence of the standard view that identical quantum particles remain indistinguishable even in the classical limit, which makes a smooth transition to the classical particle concept impossible. Lubberdink and Dieks and Lubberdink have proposed an alternative conception of quantum particles that does not rely on factorism and avoids these difficulties. We further explain and discuss this alternative framework here. One of its key consequences is that particles in quantum theory are not fundamental but emergent; another that once they have emerged, quantum particles are always physically distinguishable and thus possess a physically grounded identity. (shrink)

According to classical physics _particles_ are basic building blocks of the world. These classical particles are distinguishable objects, individuated by unique combinations of physical properties. By contrast, in quantum mechanics the received view is that particles of the same kind (“identical particles”) are physically indistinguishable from each other and lack identity. This doctrine rests on the quantum mechanical (anti)symmetrization postulates together with the “factorist” assumption that each single particle is represented in exactly one factor space of the tensor product Hilbert (...) space of a many-particle system. Even though standard in theoretical physics and the philosophy of physics, the assumption of factorism and the ensuing indistinguishability of particles are problematic. Particle indistinguishability is irreconcilable with the everyday meaning of “particle”, and also with how this term is used in the practice of physics. Moreover, it is a consequence of the standard view that identical quantum particles remain indistinguishable even in the classical limit, which makes a smooth transition to the classical particle concept impossible. Lubberdink (1998; 2009) and Dieks and Lubberdink (2011) have proposed an alternative conception of quantum particles that does not rely on factorism and avoids these difficulties. We further explain and discuss this alternative framework here. One of its key consequences is that particles in quantum theory are not fundamental but _emergent_; another that once they have emerged, quantum particles are always physically distinguishable and thus possess a physically grounded identity. (shrink)

The symmetrization postulates of quantum mechanics (symmetry for bosons, antisymmetry for fermions) are usually taken to entail that quantum particles of the same kind (e.g., electrons) are all in exactly the same state and therefore indistinguishable in the strongest possible sense. These symmetrization postulates possess a general validity that survives the classical limit, and the conclusion seems therefore unavoidable that even classical particles of the same kind must all be in the same state—in clear conflict with what we know about (...) classical particles. In this article we analyze the origin of this paradox. We shall argue that in the classical limit classical particles emerge, as new entities that do not correspond to the “particle indices” defined in quantum mechanics. Put differently, we show that the quantum mechanical symmetrization postulates do not pertain to particles, as we know them from classical physics, but rather to indices that have a merely formal significance. This conclusion raises the question of whether many discussions in the literature about the status of identical quantum particles have not been misguided. (shrink)

This thesis offers a naturalist revision of Alain Badiou’s philosophy. This goal is pursued through an encounter of Badiou’s mathematical ontology and theory of truth with contemporary trends in philosophy of mathematics and philosophy of science. I take issue with Badiou’s inability to elucidate the link between the empirical and the ontological, and his residual reliance on a Heideggerian project of fundamental ontology, which undermines his own immanentist principles. I will argue for both a bottom-up naturalisation of Badiou’s philosophical approach (...) to mathematics and a top-down naturalisation. Articulating my particular understanding of what realism and naturalism should commit us to, I propose a creative fusion of Badiou’s attention to metamathematical results with a structural-informational metaphysics, proposing a ‘matherialism’ uniting the more daring speculative insights of the former with the naturalist and empiricist commitments motivating the latter. (shrink)

In this contribution, I comment on Raffaella Campaner’s defense of explanatory pluralism in psychiatry (in this volume). In her paper, Campaner focuses primarily on explanatory pluralism in contrast to explanatory reductionism. Furthermore, she distinguishes between pluralists who consider pluralism to be a temporary state on the one hand and pluralists who consider it to be a persisting state on the other hand. I suggest that it would be helpful to distinguish more than those two versions of pluralism – different understandings (...) of explanatory pluralism both within philosophy of science and psychiatry – namely moderate/temporary pluralism, anything goes pluralism, isolationist pluralism, integrative pluralism and interactive pluralism. Next, I discuss the pros and cons of these different understandings of explanatory pluralism. Finally, I raise the question of how to implement or operationalize explanatory pluralism in scientific practice; how to structure the “genuine dialogue” or shape “the pluralistic attitude” Campaner is referring to. As tentative answers, I explore a question-based framework for explanatory pluralism as well as social-epistemological procedures for interaction among competing approaches and explanations. (shrink)

The Principle of Identity of Indiscernibles (PII) is the focus of much controversy in the history of Metaphysics and in contemporary Physics. Many questions rover the debate about its truth or falsehood, for example, to which objects the principle applies? Which properties can be counted as discerning properties? Is the principle necessary? In other words, which version of the principle is the correct and is this version true? This thesis aims to answer this questions in order to show that PII (...) is a necessarily true principle of metaphysics. To accomplish this task, the reader will find, in this thesis, an encyclopaedical introduction to the history of PII and to the reasons it matters so much, followed by a presentation of the most famous arguments against it and the defences used against these arguments. Then, the reader finds in-depth discussion of the minutiae involved in postulating the principle as to make clear what is in fact being attacked and defended. With these preliminaries solved, a deeper analysis of these defences is presented aiming to discover which is the most appropriate example to use against the attacks to the principle. This analysis allowed a classification of these defences in four families with different strategies within them. Finally, with these defensive strategies at hand we are able to confront alleged counterexamples to PII in Mathematics with the intention to test these defences. (shrink)

One might well wonder—is there a category under which every thing falls? Offering an informative account of such a category is no easy task. For nothing would distinguish things that fall under it from those that don’t—there being, after all, none of the latter. It seems hard, then, to say much about any fully general category; and it would appear to do no carving or categorizing or dividing at all. Nonetheless there are candidates for such a fully general office, including (...) thing, being, entity, item, existent, and—especially—object.[ It is not obvious that there is any fully general category (whether object or otherwise). Accordingly, not all accounts of object assign it to a fully general category, instead allowing that there are non-objects. On those views, object does indeed divide. Accounts of object, then, differ with respect to whether there are non-objects. And this is not the only fault line. Other dimensions of difference include what objects there are and what objects are. Accordingly, this entry will survey three broad questions about the category object: What, if any, is its contrast or complement? What is its extension? What is its nature? (shrink)

The paper spells out five different accounts of the relationship between objects and relations three of which are versions of ontic structural realism. We argue that the distinction between objects and properties, including relations, is merely a conceptual one by contrast to an ontological one: properties, including relations, are modes, that is the concrete, particular ways in which objects exist. We then set out moderate OSR as the view according to which irreducible relations are central ways in which the fundamental (...) physical objects exist. Physical structures thus consist in objects for whom it is essential that they are related in certain ways. There hence are objects, but they do not possess an intrinsic identity. This view can also admit intrinsic properties as ways in which objects exist provided that these do not amount to identity conditions for the objects. Finally, we indicate how this view can take objective modality into account. (shrink)

Identity. From very early days of quantum theory it was recognized that quanta were statistically strange (see !Bose-Einstein statistics). Suspicion fell on the identity of quanta, of how they are to be counted [1], [2]. It was not until Dirac’s [1902-1984] work of 1926 (and his discovery of !Fermi-Dirac statistics [3]) that the nature of the novelty was clear: the quantum state of exactly similar particles of the same mass, charge, and spin must be symmetrized, yielding states either symmetric or (...) antisymmetric under permutations. This is the symmetry postulate (SP). (shrink)

The view that quantum particles cannot be regarded as individuals was articulated in the early days of the 'quantum revolution' and became so well-entrenched that French and Krause called it 'the Received View'. However it was subsequently shown that quantum statistics is in fact compatible with a metaphysics of particle individuality, subject to certain caveats. As a consequent it has been claim that there exists a kind of underdetermination of the metaphysics by the physics which in turn has been used (...) to motivate a form of 'notice' structural realism. In this essay I will review this purported underdetermination and the motivation for structural realism that it purportedly provides in the context of recent developments in both the philosophy of physics and metaphysics. I aim to conclude that such developments reinforce the underdetermination and allow one to respond to certain critical concerns regarding its motivational power. (shrink)

One of Julian Barbour’s main aims is to solve the problem of time that appears in quantum geometrodynamics (QG). QG involves the application of canonical quantization procedure to the Hamiltonian formulation of General Relativity. The problem of time arises because the quantization of the Hamiltonian constraint results in an equation that has no explicit time parameter. Thus, it appears that the resulting equation, as apparently timeless, cannot describe evolution of quantum states. Barbour attempts to resolve the problem by allegedly eliminating (...) time from his interpretation of QG. In order to evaluate the efficacy of his solution, it is necessary to ascertain in what sense time has been eliminated from his theory. I proceed to do so by developing a form of conceptual analysis that is applicable to the concept of time in physical theories and applying this analysis to Barbour’s account. (shrink)

The present work explores various ways in which contingent evidence can impact metaphysics, while advocating that, just as a scientific realist allows for ampliative inferences to the unobservable, ampliative inferences from possible evidence can warrant possibility claims that lie beyond the reach of sensorial imagination. In slogan form: possible evidence is a guide to possibility. Drawing on Shoemaker’s (1969) argument for the possibility of time without change, I advocate the following principle: If there is a possible world at which the (...) observable facts make it objectively reasonable to conclude that p, then we should conclude that p is possibly true. This provides a route to contingentism in metaphysics, for, if one considers that there are worlds in which the observable facts make it objectively reasonable to conclude that p, and worlds in which the observable facts make it objectively reasonable to conclude that not-p, then my principle tells us that we should conclude that possibly-p and possibly not-p, i.e. that p is contingent. This contingency in what is reasonable to conclude, I suggest, occurs most saliently in debates where evidence of phenomenal experience and empirical science are marshalled to support one theory over another. I also explore some consequences of taking possible evidence to be a guide to possibility in this way, among them being an interesting modal analogue of the lottery paradox. (shrink)

This research discusses Bernard Williams' critique of utilitarianism. I will address Williams' well-known “Integrity Objection” and clarify where his main issue with utilitarianism lies. Through this, I will demonstrate that the separation of the two viewpoints – the “inside viewpoint” and the “impartial viewpoint” - is the issue, as the utilitarian impartial viewpoint does not capture the value of ethical deliberations based on our inside viewpoint in which we presuppose our personal projects. Furthermore, I will argue that this interpretation enables (...) us to place the objection in the context of the critique of impartiality which is one of the central themes of Williams’ ethics. (shrink)

It is well-known that the entangled quantum state of a composite object cannot be reduced to the states of its parts. This quantum holism provides a peculiar challenge to formulate an appropriate mereological model: When a system is in an entangled state, which objects are there on the micro and macro level, and which of the objects carries which properties? This paper chooses a modeling approach to answer these questions: It proceeds from a systematic overview of consistent mereological models for (...) entangled systems and discusses which of them is compatible with the quantum mechanical evidence (where quantum states are understood realistically). It reveals that entangled quantum systems neither describe undivided wholes nor objects that stand in irreducible relations. The appropriate model assumes that the entangled property is an irreducible non-relational plural property carried collectively by the micro objects, while there is no macro object. In this sense, quantum holism is an instance of property holism, not of object holism. (shrink)

This project investigates naturalized metaphysics as a recent trend in analytic metaphysics originating in the naturalist attitude of James Ladyman and Don Ross in their seminal work Everything must Go: Metaphysics Naturalized (2007). The primary focus, however, will be the more recent article “Neo-Positivist Metaphysics” (2012) by Alyssa Ney that originates in this tradition. The project will conclude that naturalized metaphysics is an unsuccessful attempt at an answer to the question ’how is metaphysics possible’. More precisely, the project will establish (...) that any answer to this question must instruct how to succeed at attempts at assertions about the Kantian thing in itself. This requirement is the result of an argument that no other conception of ’reality’ is robust enough to accommodate an ambitious metaphysics. Subsequently, it will be argued that naturalized metaphysics is conceived by its proponents as an attempt at such an answer, but that naturalized metaphysics does not provide the required instruction. This problem occurs because of Carnap’s challenge to metaphysics. Carnap observes that no assertion can be made outside a linguistic framework which has the consequence that metaphysical assertions must be about the conceptual conventions of the linguistic framework rather than the thing in itself. It is the view of Ney and the other proponents of naturalized metaphysics that metaphysics is possible as a naturalized metaphysics; a metaphysics that appropriately defers or yields to the findings of science. The project argues that this requirement does nothing to ensure that Carnap’s challenge is avoided. The challenge is equally significant to naturalized and non-naturalized metaphysics, so long as both require that successful attempts at metaphysics must be assertions about the thing in itself. -/- The project concludes that until or unless Carnap’s challenge is refuted, naturalized metaphysics remain impossible, just like the metaphysics it is supposed to replace. (shrink)

The composition of objects is a much discussed issue in metaphysics. In this paper I look at various approaches to this issue in the context of two examples: the relationship between ‘everyday’ objects, such as tables, and their constituent physical entities, and the relationship between structures and objects, from the perspective of structural realism. My aims are first, to defend forms of eliminativism in both cases, whereby one can still make statements about the entities to be eliminated ; and second, (...) to highlight some of the metaphysical moves that are available to the structuralist in articulating their ontology. In doing so I hope also to indicate how metaphysics and the philosophy of science can be brought into a more productive relationship. (shrink)

Physicalistic theories of psychology are a classic case of scientific imperialism: the explanatory capacity of physics, both with respect to its methods and to its domain, is taken to extend beyond the traditional realm of physics, and into that of psychology. I argue in this paper that this particular imperialistic venture has failed. Contemporary psychology uses methods not modelled on those of physics, embracing first-personal methodology where physics is strictly impersonal. I make the case that whether or not scientific imperialism (...) is in general harmful, in this instance naturalists who reject first philosophy should give up physicalist imperialism. Using only general principles from the philosophy of logic plus accepted physicalist criteria of identity, I show that first-personal psychology embodies a minor but fruitful increase in expressive strength compared to impersonal psychology: the ability to distinguish descriptively indiscriminable posits. (shrink)

In der modernen Physik spielen Symmetrien eine herausragende Rolle zur Identifikation und Klassifizierung der fundamentalen Theorien und Entitäten. Symmetrien dienen der Darstellung invarianter Strukturen, das geeignete mathematische Werkzeug hierfür ist die Gruppentheorie. Eine Struktur lässt sich als eine Menge von Relationen verstehen, die einer Menge von Objekten aufgeprägt sind. Strukturell charakterisierte Objekte sind daher wesentlich über ihre relationalen Eigenschaften charakterisiert. Sieht man die theoretischen Entitäten wissenschaftlicher Theorien vornehmlich in dieser strukturellen Weise an, vertritt man eine moderate Variante eines wissenschaftlichen Realismus, (...) die als Strukturenrealismus bekannt ist. Im Umfeld dieser drei Konzepte – Symmetrien, Strukturen, Realismus – bewegt sich der folgende Aufsatz. (shrink)

The paper is a kind of opinionated review paper on current issues in the debate about Structural Realism, roughly the view that we should be committed in the structural rather than object-like content of our best current scientific theories. The major thesis in the first part of the paper is that Structural Realism has to take structurally derived intrinsic properties into account, while in the second part key elements of aligning Structural Realism with a Humean framework are outlined.

Ladyman and Ross argue that quantum objects are not individuals and use this idea to ground their metaphysical view, ontic structural realism, according to which relational structures are primary to things. LR acknowledge that there is a version of quantum theory, namely the Bohm theory, according to which particles do have denite trajectories at all times. However, LR interpret the research by Brown et al. as implying that "raw stuff" or haecceities are needed for the individuality of particles of BT, (...) and LR dismiss this as idle metaphysics. In this paper we note that Brown et al.'s research does not imply that haecceities are needed. Thus BT remains as a genuine option for those who seek to understand quantum particles as individuals. However, we go on to discuss some problems with BT which led Bohm and Hiley to modify it. This modified version underlines that, due to features such as context-dependence and non-locality, Bohmian particles have a very limited autonomy in situations where quantum effects are non-negligible. So while BT restores the possibility of quantum individuals, it also underlines the primacy of the whole over the autonomy of the parts. The later sections of the paper also examine the Bohm theory in the general mathematical context of symplectic geometry. This provides yet another way of understanding the subtle, holistic and dynamic nature of Bohmian individuals. We finally briefly consider Bohm's other main line of research, the "implicate order", which is in some ways similar to LR's structural realism. (shrink)

This chapter outlines a metaphysics of science in the sense of a naturalized metaphysics. It considers in the first place the interplay of physics and metaphysics in Newtonian mechanics, then goes into the issues for the metaphysics of time that relativity physics raises, shows that what one considers as the referent of quantum theory depends on metaphysical considerations and finally explains how the stance that one takes with respect to objective modality and laws of nature shapes the options that are (...) available for an ontology of quantum physics. In that way, this chapter seeks to make a case for a natural philosophy that treats physics and metaphysics as inseparable in the enquiry into the constitution of the world, there being neither a neo-positivist way of deducing metaphysics from the formalisms of physical theories, nor a neo-rationalist realm of investigation for metaphysics that is independent of physics. (shrink)

The paper is an attempt to react as direct and as close as possible on Dummett’s 2007 paper by addressing his overall theses about bridging the gulfs between philosophers and physicists and between analytical and continental philosophy on the one hand and, on the other hand, picking up a couple of more detailed issues Dummett raises about physics and its philosophy.