The paper first sketches out a reply to the underdetermination challenge and the incommensurability challenge that rebuts the sceptical conclusions of these challenges and that is sufficient to lay the ground for the project of a metaphysics of nature. That metaphysics is as hypothetical as are our scientific theories. The paper then explains how can one can argue for certain views in the metaphysics of nature based on our current fundamental physical theories, namely the commitments to a tenseless theory of (...) time and existence instead of a tensed one, to events instead of substances, and to relations instead of intrinsic properties. Finally, the paper mentions the themes of causation, laws and dispositions. (shrink)

The paper argues that metaphysics depends upon science when it comes to claims about the constitution of the real world. That thesis is illustrated by considering the examples of global supervenience, the tenseless vs. the tensed theory of time and existence, events vs. substances, and relations vs. intrinsic properties. An argument is sketched out for a metaphysics of a four-dimensional block universe whose content are events and their sequences, events consisting in physical properties instantiated at space-time points, these properties being (...) relations rather than intrinsic properties. (shrink)

Carlo Rovelli's relational interpretation of quantum mechanics holds that a system's states or the values of its physical quantities as normally conceived only exist relative to a cut between a system and an observer or measuring instrument. Furthermore, on Rovelli's account, the appearance of determinate observations from pure quantum superpositions happens only relative to the interaction of the system and observer. Jeffrey Barrett ([1999]) has pointed out that certain relational interpretations suffer from what we might call the ‘determinacy problem', but (...) Barrett misclassifies Rovelli's interpretation by lumping it in with Mermin's view, as Rovelli's view is quite different and has resources to escape the particular criticisms that Barrett makes of Mermin's view. Rovelli's interpretation still leaves us with a paradox having to do with the determinacy of measurement outcomes, which can be accepted only if we are willing to give up on certain elements of the ‘absolute’ view of the world. (shrink)

This paper sets out a moderate version of metaphysical structural realism that stands in contrast to both the epistemic structural realism of Worrall and the—radical—ontic structural realism of French and Ladyman. According to moderate structural realism, objects and relations (structure) are on the same ontological footing, with the objects being characterized only by the relations in which they stand. We show how this position fares well as regards philosophical arguments, avoiding the objections against the other two versions of structural realism. (...) In particular, we set out how this position can be applied to space-time, providing for a convincing understanding of space-time points in the standard tensor formulation of general relativity as well as in the fibre bundle formulation. (shrink)

The paper argues for four claims: (1) The problem of mental causation and the argument for its solution in terms of the identity of mental with physical causes are independent of the theory of causation one favours. (2) If one considers our experience of agency as described by folk psychology to be veridical, one is committed to an anti-Humean metaphysics of causation in terms of powers that establish necessary connections. The same goes for functional properties in general. (3) A metaphysics (...) of causation in terms of powers is compatible with physics. (4) If combined with the argument for mental causes being identical with physical causes, that metaphysics leads to a conservative reductionism. (shrink)

The aim of this paper is to defend the causal homogeneity of functional, mental properties against Kim’s attack. It is argued that (a) token identity is sufficient for mental causation, that (b) token identity implies a sort of functional reduction, but that (c) nonetheless functional, mental properties can be causally homogeneous despite being multiply realizable: multiple composition is sufficient for multiple realizability, but multiple composition does not prevent the realizers from having their pertinent effects in common. Thus, the causal exclusion (...) problem provides no argument for abandoning the position that there are functional, mental properties that are natural kind properties. (shrink)

Quantum mechanics poses several challenges in ontological elucidation. Contextuality threatens determinism and favors realism about possibilia. Indistinguishability challenges traditional identity criteria associated with individual objects. Entanglement favors holistic and relational approaches. These issues, in close connection with different interpretations of quantum mechanics, have given rise to various proposals for the ontology of quantum mechanics. There is a proposal that is realistic about possibilia, where quantum systems are seen as bundles of possible intrinsic properties. This proposal is developed in close connection (...) with modal interpretations and addresses quantum contextuality straightforwardly. There are also proposals based on relations, associated with the relational quantum mechanics interpretation. In this paper, features of these proposals are combined to obtain a modal bundle-theorist relational proposal. Its aim is to consistently and straightforwardly address both contextuality and the holistic and relational aspects of quantum mechanics arising from quantum entanglement. The proposal, if some additional principles are assumed, may turn out to be both an instance of moderate structuralism and priority monism. (shrink)

The problem of the status of metaphysics -- what it is and what it is for, what use it is - has been with us for millennia, at least since Plato took issue with the Sophists, and continues to the present day. Here I attempt an intervention in this perennial dispute, with the aim of providing some kind of rapprochement between the factions. This intervention is based on how Charles Sanders Peirce (1839-1914) understood metaphysics and the position presented here is (...) thus called `Peircean realism'. The basic idea is that everyone has a metaphysics and has to have one, just to get by in everyday life, and this is no different for scientific inquirers in their professional work. The subject matter of metaphysics is thus presuppositions, whether it is what we rely on to go shopping or to discover the Higgs boson. We rely on these in our activities and expect them to have an effect on outcomes, so when our expectations are frustrated, doubt may be thrown on our presuppositions. We would thus like the ability to inquire into our presuppositions so as not to repeat mistakes, but our instinctive, evolved capacity for reasoning may not be up the job, since it is entwined with what we take for granted. Instead, Peirce develops a science of good reasoning that includes a theory of inquiry, which would allow us to scrutinise our presuppositions, to perform metaphysical inquiry. The starting point for this science of good reasoning is basic principles of combination and organisation, because these are involved in all activity, and these are Peirce's categories of Firstness, Secondness and Thirdness. This is also where I start in the exposition of and argument for Peircean realism as a scientific -- that is, truth-directed -- metaphysics that provides the best possible general presuppositions to the natural and human sciences, the special sciences that deal with matters in their particularity; that Peircean realism is a viable metaphysics for those sciences. This exposition and argument comprises the first part of this thesis. In the second part, the case for Peircean realism is further bolstered by turning a critical eye on positions that are deficient from the Peircean point of view, in that they lack one or other category and thus starve the special sciences of the resources they need, or that they try to ignore metaphysics entirely. All this is meant to demonstrate that metaphysics is unavoidable, that we need all three of Peirce's categories for a viable metaphysics for the special sciences, and that Peircean realism is just such a metaphysics. (shrink)

The black hole information loss paradox is a catch-all term for a family of puzzles related to black hole evaporation. For almost 50 years, the quest to elucidate the implications of black hole evaporation has not only sustained momentum, but has also become increasingly populated with proposals that seem to generate more questions than they purport to answer. Scholars often neglect to acknowledge ongoing discussions within black hole thermodynamics and statistical mechanics when analyzing the paradox, including the interpretation of Bekenstein-Hawking (...) entropy, which is far from settled. To remedy the dialectical gridlock, I have formulated an overarching, unified framework, which I call ``Black Hole Paradoxes'', that integrates the debates and taxonomizes the relevant `camps' or philosophical positions. -/- I demonstrate that black hole evaporation within Hawking's semi-classical framework insinuates how late-time Hawking radiation is an entangled global system, a contradiction in terms. The relevant forms of information loss are associated with a decrease in maximal Boltzmann entropy and an increase in global von Neumann entropy respectively, which engender what I've branded the ``paradox of phantom entanglement''. Prospective solutions are then tasked with demonstrating how late-time Hawking radiation is either exclusively an entangled subsystem, in which a black hole remnant lingers as an information safehouse, or exclusively an unentangled global system, in which information is evacuated to the exterior. -/- The disagreement between safehouse and evacuation solutions boils down to the statistical interpretation of thermodynamic black hole entropy, i.e., Bekenstein-Hawking entropy. Safehouse solutions attribute Bekenstein-Hawking entropy to a minority of black hole degrees of freedom, those that are associated with the horizon. Evacuation solutions, in contrast, attribute Bekenstein-Hawking entropy to all black hole degrees of freedom. I argue that the interpretation of Bekenstein-Hawking entropy is the litmus test to vet the overpopulated proposal space. So long as any proposal rejecting Hawking's original calculation independently derives black hole evaporation, globally conserves degrees of freedom and entanglement, preserves a version of semi-classical gravity at sub-Planckian scales, and describes black hole thermodynamics in statistical terms, then it counts as a genuine solution to the paradox. (shrink)

Recently, an information-theoretic structural realist theory of the self and consciousness has been put forward (Beni, M. D. 2019. Structuring the Self, Series New Directions in Philosophy and Cognitive Science. Palgrave Macmillan). The theory is presented as a form of panpsychism. I argue against this interpretation and show that Beni’s structuralist theory runs into the hard problem of consciousness, in a similar way as the Integrated Information theory of consciousness. Since both of these theories are structuralist and based on the (...) notion of information, I propose to use a solution that has been employed for Integrated Information Theory, namely introducing the distinction between extrinsic and intrinsic structure and dynamics (intrinsic information and intrinsic structure). Making these metaphysical enhancements to Beni’s structuralist theory of consciousness will give the theory a better chance of overcoming the hard problem. In terms of the metaphysics of consciousness, it takes us beyond physicalism. I then suggest that the information-theoretic structuralist theory of consciousness should, instead of panpsychism and physicalism, be combined with neutral monist ontology which is a better fit. These reworkings could lead to an improved naturalistic account of consciousness – the neutral-structuralist theory of consciousness and the self. (shrink)

I give shape to a neglected debate in metaphysics, the debate over the ontological priority between individuality and collectivity. I distinguish the debate from more familiar ones in the recent literature and articulate what I call ontological collectivism, the view that collectivity is prior to individuality. I defend the in-principle intelligibility of the view from forceful general objections and argue that not only is it coherent but also of significant interest to the literature: it allows for overlooked alternatives on a (...) variety of central discussions. (shrink)

In this paper, we evaluate some proposals that can be advanced to clarify the ontological consequences of Relational Quantum Mechanics. We first focus on priority monism and ontic structural realism and argue that these views are not suitable for providing an ontological interpretation of the theory. Then, we discuss an alternative interpretation that we regard as more promising, based on so-called ‘metaphysical coherentism’, which we also connect to the idea of an event-based, or ‘flash’, ontology.

In this article I discuss various humility theses about individuals and intrinsic properties as discussed by authors such as David Lewis. I argue that we should accept a similar humility thesis about the world’s space-time structure regardless of which metaphysics of space-time we accept. I argue this undercuts some important motivations opting in for an ontic structural realist metaphysic.

A novel non-classical mereological concept built up by blending the Metaphysics of Xavier Zubiri and the Quantum Theory of Atoms in Molecules of R. F. W. Bader is proposed. It is argued that this philosophical concept is necessary to properly account for what happens in a chemical reaction. From the topology of the gradient of the laplacian of the electronic charge density, \\) within the QTAIM framework, different “atomic graphs” are found for each atom depending on the molecular context, reflecting (...) how the whole molecule affects each atom. In this way, the whole molecular system imposes certain geometry onto each atom, and every atom exhibits different ontological modality. On the Metaphysical side, for X. Zubiri real things are system of different notes. The physical essence is the subsystem of essential notes with a coherence unity. Every note is grounded on the essence. The unity of the system is present somehow in every note-of beforehand, and every essential note-of turns towards the other. The essence determines the position of each note within the system, and hence is the grounding for modality of the notes. By conflating both “theories” and taking the atoms as essential notes, we propose the concept of “Molecule in atoms-of” or “atoms-of in Molecules”. Within the course of a chemical reaction the atoms-of modified their “of” as required by the new molecular unity being formed, and eventually change their modality. The validity to the Zubiri’s statements, is attained by evaluating necessity and possibility in a set-up of finite accessible “possible worlds”. (shrink)

Ontic Structural Realism, as pivotal position in philosophy of science and metaphysics, defends the idea that the world is ultimately constituted of real physical structures. French (2014) regards physical symmetries as the foundational structure of a world without objects. On the other hand, Ladyman and Ross (2007) hold that the world is essentially made of non-redundant informational structure. I argue in this paper that these two positions are by no means incompatible, for instance by interpreting French’s physical symmetries as real (...) structures both encompassing and compressing every piece of information (Kolmogorov complexity) within the world. (shrink)

In this paper, it is argued that Aristotelian hylomorphism can supply a useful and informative account of composite entities as these are described by physical theory. In particular, a hylomorphic account of quantum entangled systems is defined in detail, and compared to other alternatives currently on offer—in particular, ontic structural realism. In closing, it is suggested that the view of entanglement outlined here meshes well with a recently proposed ‘coherentist’ conception.

I begin by giving reasons to accept the block-universe view, the strongly supported by physics view that we live in a four-dimensional world. According to it, the past and the future are as real as the present. As a result, it seems that the future is determined in the sense that what will be the case will necessarily be the case. In the dissertation, I examine whether we have to accept this consequence. I show that we do not have to (...) bite the bullet: the future might be both real and contingent. I first start to consider modal realism (possible futures are real) as a possible solution. However, I propose then another account, actualist (positing the reality of only one possible world: the space-time we live in). This solution relies on a conventionalist theory about metaphysical modality (Sidelle, 1989). It states that modal modality is purely conventional. In combination with a realist interpretation of natural modality (causal and/or nomological), this framework allows me to propose that the future is conventionally closed and naturally contingent. In this view, the necessity of the future holds in virtue of linguistic conventions and then is conventionally necessary. But this is a distinct phenomenon from the natural contingency of the future: the future is naturally contingent because there are mind-independent probabilistic relations holding between the present and the future. This solution has strong consequences: most importantly, an anti-realist view about ordinary objects and physical particles. I end up by presenting and arguing in favour of the general image of the world that comes out from these views. (shrink)

The present paper argues that the typical structuralist claims according to which invariances, symmetries and the like are fundamental – especially in physics – should not be understood in terms of physical relations being fundamental. Rather, they should be understood in terms of ‘metaphysical coherentism’ - the idea that object-like parts of reality exhibit symmetric relations of ontological dependence. The view is developed in some detail, in particular by showing that i) symmetric ontological dependence does not necessarily lead to uninformative (...) metaphysical explanations, and ii) metaphysical coherentism strikes the best balance between the requirements of naturalism and those of theoretical consistency – especially in view of the difficulties that structuralists seem to have in accounting for all state-independent properties of particles in relational terms. On this basis, the coherentist picture is applied to the interpretation of the quantum domain, and contrasted with extant varieties of structuralism, of both the eliminative and the non-eliminative sort, and holism. (shrink)

Discutindo acerca das centenas de detecções de planetas extrassolares, que supostamente aconteceram desde 1989 e que ele considera (incorretamente) como instâncias de observações, Peter Kosso disse, justamente, que segundo os parâmetros de Bas van Fraassen esses objetos celestes seriam observáveis. Ora, tais astros poderiam sem dúvida ser observados diretamente (sem a necessidade de instrumentos), nas condições apropriadas. Mas, acrescenta Kosso, “esse tipo de epistemologia externalista, que permite que a justificação se baseie em informação que não temos a disposição (nós não (...) estamos em condição de ver planetas extrassolares a olho nu [atualmente]), não ajuda a decidir quais particulares afirmações científicas garantem a crença” (Kosso 2006, 225, nota 1). Van Fraassen provavelmente incorre em uma petição de princípio não muito diferente daquelas que ele muitas vezes desmascarou em textos de autores realistas, quando apela para o fato de o objeto detectado ser observável, para atribuir o estatuto de ‘observação’ a uma certa detecção. O ponto é, mais uma vez, entender o que vale como observação, particularmente quando isso envolve o uso de algum instrumento. Endossar aquilo que Otávio Bueno chama de ‘padrão internalista’ parece garantir solidez à qualificação de determinadas ações como observações. Uma das principais consequências dessa adoção é que tal critério, não operando nenhuma distinção relevante entre detecções ‘diretas’ e detecções mediadas por instrumentos, permite que a linha que separa observáveis e inobserváveis seja traçada de maneira diferente de como van Fraassen acredita que deveria ser, abarcando, entre os observáveis, mais (tipos de) entidades do que esse parece estar disposto a admitir. (shrink)

In this brief paper, we argue about some epistemological positions about quantum non-locality.

The procedures of canonical quantization of the gravitational field apparently lead to entities for which any interpretation in terms of spatio-temporal localization or spatio-temporal extension seems difficult. This fact is the main ground for the suggestion that can often be found in the physics literature on canonical quantum gravity according to which spacetime may not be fundamental in some sense. This paper aims to investigate this radical suggestion from an ontologically serious point of view in the cases of two standard (...) forms of canonical quantum gravity, quantum geometrodynamics and loop quantum gravity. We start by discussing the physical features of the quantum wave functional of quantum geometrodynamics and of the spin networks of loop quantum gravity that motivate the view according to which spacetime is not fundamental. We then point out that, by contrast, for any known ontologically serious understanding of quantum entanglement, the commitment to spacetime seems indispensable. Against this background, we then critically discuss the idea that spacetime may emerge from more fundamental entities. As a consequence, we finally suggest that the emergence of classical spacetime in canonical quantum gravity faces a dilemma: either spacetime ontologically emerges from more fundamental non-spatio-temporal entities or it already belongs to the fundamental quantum gravitational level and the emergence of the classical picture is merely a matter of levels of description. On the first horn of the dilemma, it is unclear how to make sense of concrete physical entities that are not in spacetime and of the notion of ontological emergence that is involved. The second horn runs into the difficulties raised by the physics of canonical quantum gravity. (shrink)

The existence of non-local correlations between outcomes of measurements in quantum entangled systems strongly suggests that we are dealing with some form of causation here. An assessment of this conjecture in the context of the collapse interpretation of quantum mechanics is the primary goal of this paper. Following the counterfactual approach to causation, I argue that the details of the underlying causal mechanism which could explain the non-local correlations in entangled states strongly depend on the adopted semantics for counterfactuals. Several (...) relativistically-invariant interpretations of spatiotemporal counterfactual conditionals are discussed, and the corresponding causal stories describing interactions between parts of an entangled system are evaluated. It is observed that the most controversial feature of the postulated causal connections is not so much their non-local character as a peculiar type of circularity that affects them. (shrink)

Delayed-choice experiments in quantum mechanics are often taken to undermine a realistic interpretation of the quantum state. More specifically, Healey has recently argued that the phenomenon of delayed-choice entanglement swapping is incompatible with the view that entanglement is a physical relation between quantum systems. This paper argues against these claims. It first reviews two paradigmatic delayed-choice experiments and analyzes their metaphysical implications. It then applies the results of this analysis to the case of entanglement swapping, showing that such experiments pose (...) no threat to realism about entanglement. (shrink)

Well known quantum and time paradoxes, and the difficulty to derive the second law of thermodynamics, are proposed to be the result of our historically grown paradigm for energy: it is just there, the capacity to do work, not directly related to change. When the asymmetric nature of energy is considered, as well as the involvement of energy turnover in any change, so that energy can be understood as fundamentally "dynamic", and time-oriented, these paradoxes and problems dissolve. The most basic (...) consequence concerns the particle-wave dualism. For a reversible inter-conversion of a particle into a wave, subject to a dynamic energy, a self-image of information has to be generated: quantum theory has to be complemented by a theory of information. Then, quantum processes can be derived from classical ones and the second law of thermodynamics with the tendency of increasing entropy follows in a straightforward way. (shrink)

We set out a fundamental ontology of atomism in terms of matter points. While being most parsimonious, this ontology is able to match both classical and quantum mechanics, and it remains a viable option for any future theory of cosmology that goes beyond current quantum physics. The matter points are structurally individuated: all there is to them are the spatial relations in which they stand; neither a commitment to intrinsic properties nor to an absolute space is required. The spatial relations (...) change. All that is needed to capture change is a dynamical structure, namely dynamical relations as expressed in terms of the dynamical parameters of a physical theory. (shrink)

In recent literature, it has become clear that quantum physics does not refute Humeanism: Lewis’s thesis of Humean supervenience can be literally true even in the light of quantum entanglement. This point has so far been made with respect to Bohm’s quantum theory. Against this background, this paper seeks to achieve the following four results: to generalize the option of quantum Humeanism from Bohmian mechanics to primitive ontology theories in general; to show that this option applies also to classical mechanics; (...) to establish that it requires a commitment to matter as primitive stuff, but no commitment to natural properties ; to point out that by removing the commitment to properties, the stock metaphysical objections against Humeanism from quidditism and humility no longer apply. In that way, quantum physics strengthens Humeanism instead of refuting it. (shrink)

Traditionally one main emphasis of the quantum mechanical measurement theory is on the question how the pure state of the compound system 'measured system + measuring apparatus' is transformed into the 'mixture' of all possible results of that measurement, weighted with their probability: the so-called “disappearance of the interference terms”. It is argued in this note that in reality there is no such transformation, so that there is no need to account for such a transformation theoretically. _German_ Gewöhnlich liegt ein (...) Hauptgewicht der quantenmechanischen Messtheorie auf der Frage des Übergangs vom,reinen Fall' des Gesamtsystems,gemessenes System + Messgerät' in das,Gemenge' aus allen möglichen Messergebnissen, gewichtet mit ihren Wahrscheinlichkeiten: Das sog.,,Verschwinden der Interferenzterme“. In dieser Notiz wird die Meinung vertreten, dass es einen solchen Übergang faktisch nicht gibt, so dass es nicht notwendig ist, eine theoretische Erklärung für den Übergang zu geben. (shrink)

This paper explores some of the consequences of quantum entanglement for the mainstream metaphysician. The basic idea that entanglement has metaphysical consequences in the form of some kind of “holism” is familiar in the philosophy of physics literature, and finds its way into recent metaphysics, in discussions of failure of Humean supervenience, monism and emergence, for example. The principle aim here is to highlight some questions of detail that occur when attempting to make contact with those metaphysical debates as they (...) occur in the metaphysics literature-details that matter less when the aim is just to show that there is some novelty in entanglement, but more when articulating its precise nature. The conclusion is broadly that the differences are not as great as is sometimes supposed between entanglement and more familiar phenomena already accommodated in prominent metaphysical schemes. (shrink)

The paper has two aims: (1) it sets out to show that it is well motivated to seek for an account of quantum non-locality in the framework of ontic structural realism (OSR), which integrates the notions of holism and non-separability that have been employed since the 1980s to achieve such an account. However, recent research shows that OSR on its own cannot provide such an account. Against this background, the paper argues that by applying OSR to the primitive ontology theories (...) of quantum physics, one can accomplish that task. In particular, Bohmian mechanics offers the best prospect for doing so. (2) In general, the paper seeks to bring OSR and the primitive ontology theories of quantum physics together: on the one hand, in order to be applicable to quantum mechanics, OSR has to consider what the quantum ontology of matter distributed in space-time is. On the other hand, as regards the primitive ontology theories, OSR provides the conceptual tools for these theories to answer the question of what the ontological status of the wave-function is. (shrink)

We address an argument by Floridi (Synthese 168(1):151–178, 2009; 2011a), to the effect that digital and analogue are not features of reality, only of modes of presentation of reality. One can therefore have an informational ontology, like Floridi’s Informational Structural Realism, without commitment to a supposedly digital or analogue world. After introducing the topic in Sect. 1, in Sect. 2 we explain what the proposition expressed by the title of our paper means. In Sect. 3, we describe Floridi’s argument. In (...) the following three sections, we raise three difficulties for it, (i) an objection from intuitions: Floridi’s view is not supported by the intuitions embedded in the scientific views he exploits (Sect. 4); (ii) an objection from mereology: the view is incompatible with the world’s having parts (Sect. 5); (iii) an objection from counting: the view entails that the question of how many things there are doesn’t make sense (Sect. 6). In Sect. 7, we outline two possible ways out for Floridi’s position. Such ways out involve tampering with the logical properties of identity, and this may be bothersome enough. Thus, Floridi’s modus ponens will be our (and most ontologists’) modus tollens. (shrink)

Quantum decoherence is receiving a great deal of attention today not only in theoretical and experimental physics but also in branches of science as diverse as molecular biology, biochemistry, and even neuropsychology. It is no surprise that it is also beginning to appear in various philosophical debates concerning the fundamental structure of the world. The purpose of this article is primarily to acquaint non-specialists with quantum decoherence and clarify related concepts, and secondly to sketch its possible implications – independent of (...) particular interpretations of quantum mechanics – for broader philosophical debates. For example, decoherence shows that any method of parsing nature into levels or parts cannot be in principle but instead derives from our perception of the world as classical, a perception that is itself sustained by the process of decoherence. (shrink)

In this article, I address concerns that the ontological priority claims definitive of ontic structural realism are as they stand unclear, and I do so by placing these claims on a more rigorous formal footing than they typically have been hitherto. I first of all argue that Kit Fine’s analysis of ontological dependence furnishes us with an ontological priority relation that is particularly apt for structuralism. With that in place, and with reference to two case studies prominent within the structuralist (...) literature, I consider whether any of structuralism’s distinctive priority claims may be regarded as warranted. The discussion as a whole has largely negative implications for the radical structuralism of French and Ladyman (including their ‘eliminativist’ interpretation of it), largely positive implications for the moderate structuralism primarily advocated by Esfeld and Lam, and some broad lessons for contemporary fundamentalist metaphysics as a whole. 1 Introduction2 The Right Priority Relation for Structuralism: Supervenience or Dependence?3 Introducing Ontological Dependence4 Fine’s System5 The Priority of Structure 1: Entangled Quantum Particles6 The Priority of Structure 2: The Group-Theoretic Conception of Elementary Particles7 Concluding Remarks. (shrink)

[ENGLISH] The present article is a contribution to the development of metrological structural realism. This position of philosophy of science goes back to Matthias Neuber, who introduces it as a third variation of the main structural realisms: epistemic structural realism and ontic structural realism. Here, Neuber attempts to tackle the problems of OSR and ESR while preserving their respective strengths. Of central importance to his approach, are the concepts of invariance, structure and, especially, measurement. Starting from Eino Kaila’s „non-linguistic, realist (...) account of logical empricism“, the present article investigates the necessity of yet another position of structural realism. The established structural realisms are examined for their strengths and weaknesses. Afterwards, the requirements on MSR are formulated in a way that extends beyond Neuber’s account. These requirements are of ontological, epistemological and metrological nature. -/- [DEUTSCH] Der vorliegende Aufsatz ist ein Beitrag zur Entwicklung des Metrologischen Strukturenrealismus. Diese Wissenschaftstheoretische Position geht auf Matthias Neuber zurück, der sie als dritte Spielart zwischen den großen Strukturenrealismen – dem Epistemischen Strukturenrealismus und dem Ontischen Strukturenrealismus – ansiedelt. Neuber versucht, die wissenschaftstheoretischen Probleme von ESR und OSR anzugehen, gleichzeitig aber ihre jeweiligen Stärken beizubehalten. Dabei sind die Konzepte der Invarianz, der Struktur und besonders der Messung von zentraler Bedeutung. Ausgehend von Eino Kailas „non-linguistic, realist account of logical empiricism“ untersucht der vorliegende Aufsatz die Notwendigkeit einer weiteren strukturenrealistischen Position. Dazu werden die etablierten Strukturenrealismen auf ihre Stärken und Schwächen hin untersucht. Es folgt eine Ausformulierung der Forderungen an den MSR, die über die Darstellung bei Neuber hinaus geht. Diese Forderungen sind ontologischer, epistemischer und metrologischer Natur. (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)

The paper compares ontic structural realism in quantum physics with ontic structural realism about space–time. We contend that both quantum theory and general relativity theory support a common, contentful metaphysics of ontic structural realism. After recalling the main claim of ontic structural realism and its physical support, we point out that both in the domain of quantum theory and in the domain of general relativity theory, there are objects whose essential ways of being are certain relations so that these objects (...) do not possess an intrinsic identity. Nonetheless, the qualitative, physical nature of these relations is in the quantum case (entanglement) fundamentally different from the classical, metrical relations treated in general relativity theory. (shrink)

Delayed-choice experiments in quantum mechanics are often taken to undermine a realistic interpretation of the quantum state. More specifically, Healey has recently argued that the phenomenon of delayed-choice entanglement swapping is incompatible with the view that entanglement is a physical relation between quantum systems. This paper argues against these claims. It first reviews two paradigmatic delayed-choice experiments and analyzes their metaphysical implications. It then applies the results of this analysis to the case of entanglement swapping, showing that such experiments pose (...) no threat to realism about entanglement. (shrink)

In this paper I argue that it is finally time to move beyond the Nagelian framework and to break new ground in thinking about epistemic reduction in biology. I will do so, not by simply repeating all the old objections that have been raised against Ernest Nagel’s classical model of theory reduction. Rather, I grant that a proponent of Nagel’s approach can handle several of these problems but that, nevertheless, Nagel’s general way of thinking about epistemic reduction in terms of (...) theories and their logical relations is entirely inadequate with respect to what is going on in actual biological research practice. (shrink)

It has been widely noted that Humean supervenience , according to which everything supervenes on intrinsic properties of point-sized things and the spatiotemporal relations between them, is at odds with the nonlocal character of quantum mechanics, according to which not everything supervenes on intrinsic properties of point-sized things and the spatiotemporal relations between them. In particular, a standard view is that the parts of a composite quantum system instantiate further relations which are not accounted for in Lewis's Humean mosaic. But (...) that suggests a simple solution: Why couldn't Lewis simply add these new relations to the supervenience basis? The aim of this article is to use Humean supervenience as a foil to spell out a feature of entanglement of general metaphysical interest: The way in which the metaphysical lessons drawn for two-party systems ramify when systems of many parties are considered. The main conclusion is that the proposed simple fix in fact results in a supervenience thesis different in kind from Lewis's, by making the relations in the supervenience basis global in a certain sense. (shrink)

Recently, there has been a debate as to whether or not the principle of the identity of indiscernibles (the PII) is compatible with quantum physics. It is also sometimes argued that the answer to this question has implications for the debate over the tenability of ontic structural realism (OSR). The central aim of this paper is to establish what relationship there is (if any) between the PII and OSR. It is argued that one common interpretation of OSR is undermined if (...) the PII turns out to be false, since it is committed to a version of the bundle theory of objects, which implies the PII. However, if OSR is understood as the physical analogue of (sophisticated) mathematical structuralism then OSR does not imply the PII. It is further noted that it is (arguably) a virtue of OSR that it is compatible with a version of the PII for possible worlds. (shrink)

Using the Hilbert-Bernays account as a spring-board, we first define four ways in which two objects can be discerned from one another, using the non-logical vocabulary of the language concerned. Because of our use of the Hilbert-Bernays account, these definitions are in terms of the syntax of the language. But we also relate our definitions to the idea of permutations on the domain of quantification, and their being symmetries. These relations turn out to be subtle---some natural conjectures about them are (...) false. We will see in particular that the idea of symmetry meshes with a species of indiscernibility that we will call `absolute indiscernibility'. We then report all the logical implications between our four kinds of discernibility. We use these four kinds as a resource for stating four metaphysical theses about identity. Three of these theses articulate two traditional philosophical themes: viz. the principle of the identity of indiscernibles, and haecceitism. The fourth is recent. Its most notable feature is that it makes diversity weaker than what we will call individuality : two objects can be distinct but not individuals. For this reason, it has been advocated both for quantum particles and for spacetime points. Finally, we locate this fourth metaphysical thesis in a broader position, which we call structuralism. We conclude with a discussion of the semantics suitable for a structuralist, with particular reference to physical theories as well as elementary model theory. (shrink)

In a naïve realist approach to reading an ontology off the models of a physical theory, the invariance of a given theory under permutations of its property-bearing objects entails the existence of distinct possible worlds from amongst which the theory cannot choose. A brand of Ontic Structural Realism attempts to avoid this consequence by denying that objects possess primitive identity, and thus worlds with property values permuted amongst those objects are really one and the same world. Assuming that any successful (...) ontology of objects is able to describe a universe containing a determinate number of them, I argue that no version of OSR which both retains objects and understands ‘structure’ in terms of relations can be successful. This follows from the fact that no set of relational facts is sufficient to fix the cardinality of the collection of objects implied by those facts. More broadly, I offer reasons to believe that no version of OSR is compatible with the existence of objects, no matter how ontologically derivative they are taken to be. Any such account would have to attribute a definite cardinality to a collection of objects while denying that those objects are possessed of a primitive identity. With no compelling reason to abandon the classical conception of cardinality, such an attribution is incoherent. (shrink)

It is shown that Lewis’ ontological doctrine of Humean supervenience incorporates at its foundation the so-called separability principle of classical physics. In view of the systematic violation of the latter within quantum mechanics, the claim that contemporary physical science may posit non-supervenient relations beyond the spatiotemporal ones is reinforced on a foundational basis concerning constraints on the state representation of physical systems. Depending on the mode of assignment of states to quantum systems — unit state vectors versus statistical density operators (...) — we distinguish between strongly and weakly non-Humean, non-supervenient relations. It is demonstrated that in either case, the relations of quantum entanglement constitute prototypical examples of irreducible physical relations that do not supervene upon a spatiotemporal arrangement of Humean qualities, weakening, thereby, the thesis of Humean supervenience. In this respect, the status of Lewis’ recombination principle is examined, whereas his conception of lawhood is critically investigated. It is concluded that the assumption of ontological reductionism, as expressed in Lewis’ Humean doctrine, cannot be regarded as a reliable code of the nature of the physical world and its contents. It is proposed instead that due to the undeniable existence of non-supervenient relations, a metaphysic of relations of a moderate kind ought to be acknowledged as an indispensable part of our understanding of the natural world at a fundamental level. (shrink)

Structural realism is sometimes said to undermine the theory underdetermination (TUD) argument against realism, since, in usual TUD scenarios, the supposed underdetermination concerns the object-like theoretical content but not the structural content. The paper explores the possibility of structural TUD by considering some special cases from modern physics, but also questions the validity of the TUD argument itself. The upshot is that cases of structural TUD cannot be excluded, but that TUD is perhaps not such a terribly serious anti-realistic argument.

In this paper we argue that physical theories, including quantum mechanics, refer to some kind of ‘objects’, even if only implicitly. We raise questions about the logico-mathematical apparatuses commonly employed in such theories, bringing to light some metaphysical presuppositions underlying such apparatuses. We point out to some incongruities in the discourse holding that quantum objects would be entities of some ‘new kind’ while still adhering to the logico-mathematical framework we use to deal with classical objects. The use of such apparatus (...) would hinder us from being in complete agreement with the ontological novelties the theories of quanta seem to advance. Thus, we join those who try to investigate a ‘logic of quantum mechanics’, but from a different point of view: looking for a formal foundation for a supposed new ontology. As a consequence of this move, we can revisit Einstein’s ideas on physical reality and propose that, by considering a new kind of object traditionally termed ‘non-individuals’, it is possible to sustain that they still obey some of Einstein’s conditions for ‘physical realities’, so that it will be possible to talk of a ‘principle of separability’ in a sense which is not in complete disagreement with quantum mechanics. So, Einstein’s departure from quantum mechanics might be softened at least concerning a form of his realism, which sees separated physical objects as distinct ‘physical realities’. (shrink)

The paper first argues that if one takes current fundamental physics seriously, one gets to a metaphysics of events and relations in contrast to substances and intrinsic properties. Against that background, the paper discusses Heil’s theory of properties being both categorical and dispositional and his rejection of levels of being. I contrast these views with a Humean metaphysics. My concluding claim is that Heil’s account of properties opens up the perspective of a conservative reductionism, which avoids the common reservations against (...) reductionism. (shrink)

This article examines the relationship between science and theology within a critical realist framework. Focusing on the role of metaphysics as a unifying starting point, especially in consideration of theological issues that are concerned with corporeality and temporality (such as in the incarnation). Some metaphysical challenges that lead to the appearance of “paradox” in the incarnation are highlighted, and the implications of two forms of holistic scientific ontology on the appearance of a paradox in the incarnation are explored. It is (...) concluded that ultimately both science and theology are concerned with the nature of reality, and the search for coherent models that can describe the unseen. Whilst one should maintain a criticality to any realist conception of theological and scientific theories, a shared metaphysics ensures theological doctrine can continue to be interpreted with relevance in a world in which scientific thought is increasingly stretching into the meta-scientific. (shrink)

The paper explores a particular line of objection against wave-function realism. This view, advocated by Bell and presently defended by Albert, North and Ney, claims tha...

Distance, it is often argued, is the only coherent and empirically adequate world-making relation that can glue together the elements of the world. This paper offers entanglement as an alternative world-making relation. Entanglement is interesting since it is consistent even with quantum gravity theories that do not feature space at the fundamental level. The paper thereby defends the metaphysical salience of such non-spatial theories. An account of distance is the predominant problem of empirical adequacy facing entanglement as a world-making relation. (...) A resolution of this obstacle utilizes insights from the Ryu–Takayanagi formula and Susskind and Maldacena’s related ER = EPR conjecture. Together these indicate how distance can be recovered from entanglement and thus carves the way for entanglement fundamentalism. (shrink)