Structural Realism

Although scientific realism is the default position in the life sciences, philosophical accounts of realism are geared towards physics and run into trouble when applied to fields such as biology or neuroscience. In this paper, I formulate a new robustness-based version of entity realism, and show that it provides a plausible account of realism for the life sciences that is also continuous with scientific practice. It is based on the idea that if there are several independent ways of measuring, detecting (...) or deriving something, then we are justified in believing that it is real. I also consider several possible objections to robustness-based entity realism, discuss its relationship to ontic structural realism, and show how it has the potential to provide a novel response to the pessimistic induction argument. (shrink)

This paper aims to set forth Carnapian structuralism, i.e., a syntactic view of the structuralist approach which is deeply inspired by Carnap’s dual level conception of scientific theories. At its core is the axiomatisation of a metatheoretical concept AE(T) which characterises those extensions of an intended application that are admissible in the sense of being models of the theory-element T and that satisfy all links, constraints and specialisations. The union of axiom systems of AE(T) (where T is an element of (...) the theory-net N) will allow us to present scientific theories in an axiomatic fashion so that deductive reasoning in science can be formalised. Thereupon defeasible and paraconsistent means of reasoning will be introduced. The logical study of scientific reasoning is the key motivation of Carnapian structuralism. A further motivation is to help overcome the syntactic-semantic split in the philosophy of science. (shrink)

In this paper, I address the issue of scientific modelling in contemporary linguistics, focusing on the generative tradition. In so doing, I identify two common varieties of linguistic idealisation, which I call determination and isolation respectively. I argue that these distinct types of idealisation can both be described within the remit of Weisberg’s :639–659, 2007) minimalist idealisation strategy in the sciences. Following a line set by Blutner :27–35, 2011), I propose this minimalist idealisation analysis for a broad construal of the (...) generative linguistic programme and thus cite examples from a wide range of linguistic frameworks including early generative syntax, Minimalism, the parallel architecture and optimality theory. Lastly, I claim that from a modelling perspective, the dynamic turn in syntax can be explained as a continuation, as opposed to a marked shift, of the generative modelling paradigm. Seen in this light, my proposal is an even broader construal of the generative tradition, along scientific modelling lines. Thus, I offer a lens through which to appreciate the scientific contribution of generative grammar, amid an increased resistance to some of its core theoretical posits, in terms of a brand of structural realism in the philosophy of science and specifically scientific modelling. (shrink)

Structural realism has been suggested as the best compromise in the debate on scientific realism. It proposes that we should be realist about the relational structure of the world, not its nature. However, it faces an important objection, first raised by Newman against Russell: if relations are not qualified, then the position is either trivial or collapses into empiricism, but if relations are too strongly qualified, then it is no longer SR. A way to overcome this difficulty is to talk (...) about modal, or nomological relations instead of purely extensional relations. I argue that this is insufficient, for then, SR collapses into modal empiricism. I suggest, however, that ME could be the best position in the debate on scientific realism. 1Introduction2Objections to Structural Realism3How to Escape Newman’s Objection4Which Modal Relations Are Retained in Theory Change?5Are Modal Relations Real?6Relativity and Fundamentality7Is Modal Empiricism Really Empiricism?8Could Modal Empiricism Be the Best of Both Worlds? (shrink)

Structural realism is a flavour of scientific realism that argues we can know about the unobservable world because we can know about its structure. This paper presents the hitherto dormant ‘ontological problem’ for structural realism. It does so by recalling the now (in)famous ‘Newman Problem’ which is said to undercut the entire structural realist project by showing the favoured definition of structure to be trivial and weak. In the paper, I suggest the Newman Problem is actually symptomatic of a more (...) pressing ontological problem—that structural realism has yet to provide an adequate account of what kind of a ‘thing’ structure is. With the issue laid out, I present two interpretations of structural realism that I think do attempt to provide an ontological basis for structure. I argue that while they may have difficulties that need working out, both are largely promising. (shrink)

Privileged-perspective realism (PPR) is a version of metaphysical realism that takes certain irreducibly perspectival facts to be partly constitutive of reality. PPR asserts that there is a single metaphysically privileged standpoint from which these perspectival facts obtain. This chapter discusses several views that fall under the category of privileged-perspective realism. These include presentism, which is PPR about tensed facts, and non-multiverse interpretations of quantum mechanics, which the chapter argues, constitute PPR about world-indexed facts. Using the framework of the bird perspective (...) and the frog perspective, it argues that PPR views methodologically treat the frog perspective as metaphysically primary. This chapter considers case studies of metaphysical interpretations of special relativity and quantum mechanics in order to demonstrate that such motivations for PPR are non-naturalistic. Further, it considers psychological factors that motivate the appeal of PPR views and offers naturalistic explanations of why we should not expect them to produce an adequate metaphysics of science. (shrink)

John Worrall (1989) famously claimed that structural realism is the best of both worlds; it enables one to endorse the best arguments for scientific realism and antirealism. In this paper, I argue that structural realism also enables one to combine two other seemingly inconsistent positions: realism and pluralism. Indeed, the very features which form the basis of the structural realist’s reply to the problem of theory change may be applied synchronically to allow for a pluralist structural realism. The resulting position (...) incorporates a robust variety of scientific pluralism unavailable to the traditional realist and thereby allows the structural realist to take seriously the pluralism apparent in scientific practice. (shrink)

I argue that the central conflict between epistemic and ontic versions of structural realism concerns whether it is possible to read off ontology from current fundamental science. Even if we assume that structures are metaphysically superior to objects, the possibility of reading off ontology from current fundamental science remains unjustified. I show that the conclusion as regards to the reading off ontology in the ontic version is already assumed in one of the premises; hence the argument begs the question. As (...) a result, the problem of ontological discontinuity implied in the pessimistic meta-induction argument remains intact in ontic structural realism. (shrink)

In metaphysics, fundamentality is a central theme involving debates on the nature of existents, as wholes. These debates are largely object-oriented in their standpoint and engage with composites or wholes through the mereological notion of compositionality. The ontological significance of the parts overrides that of wholes since the existence and identity of the latter are dependent on that of the former. Broadly, the candidates for fundamental entities are considered to be elementary particles of modern physics (since they appear to play (...) the role of ultimate parts to all phenomena). The paper intends to show the inadequacy of the object-oriented notion of conditionality by pointing out that the parts and wholes possess varying conditions of existence. By alleging that only the parts are ontologically significant is to conflate such conditions and neglect the spectrum of conditions which exist in our world. A proposal for a revised notion of compositionality in terms of structural relatedness is also put forward. (shrink)

Twenty years ago John Worrall offered an alleged non-standard viable form of scientific realism under the name structural realism. Structural realism was supposed to be both an alternative to standard scientific realism and a viable form of realism. The central questions addressed in this paper are what I call the two dogmas of structural realism: the idea that there is structure retention across theory change, and the idea that theoretical structures describe the world. Arthur Fine proclaimed that scientific realism was (...) dead. I claim that Worrall's attempt to bring scientific realism back to life has failed. John Worrall ofreció hace veinte años una forma no típica, supuestamente viable, de realismo científico a la que llamó realismo estructural. Se suponía que éste era una alternativa al realismo típico y una forma viable de realismo. Las cuestiones principales que discuto en este artículo son lo que denomino los dos dogmas del realismo estructural: la idea de que hay retención de estructura en el cambio teórico, y la idea de que las estructuras teóricas describen el mundo. Arthur Fine proclamó que el realismo científico había muerto. Yo afirmo que el intento de Worrall de resucitar el realismo científico ha fracasado. (shrink)

What is it reasonable to believe about our most successful scientific theories such as the general theory of relativity or quantum mechanics? That they are true, or at any rate approximately true? Or only that they successfully ‘save the phenomena’, by being ‘empirically adequate’? In earlier work I explored the attractions of a view called Structural Scientific Realism. This holds that it is reasonable to believe that our successful theories are structurally correct. In the first part of this paper I (...) shall explain in some detail what this thesis means and outline the reasons why it seems attractive. The second section outlines a number of criticisms that have none the less been brought against SSR in the recent literature; and the third and final section argues that, despite the fact that these criticisms might seem initially deeply troubling, the position remains viable. (shrink)

Several recent authors identify structural realism about scientific theories with the claim that the content of a scientific theory is expressible using its Ramsey sentence. Many of these authors have also argued that so understood, the view collapses into empiricist anti-realism, since an argument originally proposed by Max Newman in a review of Bertrand Russell’s The analysis of matter demonstrates that Ramsey sentences are trivially satisfied, and cannot make any significant claims about unobservables. In this paper I argue against both (...) of these claims. Structural realism and Ramsey sentence realism are, in their most defensible versions, importantly different doctrines, and neither is committed to the premises required to demonstrate that they collapse into anti-realism.Keywords: Ramsey sentence; Structural realism; Structuralism; Scientific realism. (shrink)

This impressive volume presents the results of a symposium on the structure of scientific theories held at the University of Illinois, Urbana, on March 26-29, 1969; lest this create the wrong impression, let it be noted at the outset that the volume is much more than a collection of papers. Indeed, when one takes into account Frederick Suppe’s book-length introduction, the editing of the critical comments, the extensive bibliography, and the fine index, the work must be seen as the best (...) account of scientific theory now available, one that surely commends itself to every philosopher of science with the slightest interest in metaphysics. The thrust of the symposium was to examine the view of scientific theories that has enjoyed great vogue among logical positivists, who have seen such theories as "axiomatic calculi in which theoretical terms and statements are given a partial observational interpretation by means of correspondence rules." Suppe refers to this as the "Received View," although it has been increasingly questioned in recent years, particularly by philosophers who have some proficiency in the history of science and by scientists who question its fidelity to actual scientific practice. One of the major aims of the symposium was to subject the Received View to analysis and debate by its proponents and by its critics, to assess its present status, and to see if any consensus has begun to develop on this topic—which plays such a key role in the philosophy of science. Suppe performs the analytic function in his critical introduction, and Stephen Toulmin adds a postscript that attempts to chart a course for future research. The message seems to be that the Received View has run its course and has proved to be more a hindrance than a help to philosophizing about science; what will take its place, however, does not emerge with any clarity. Participants in the symposium include all the luminaries in the philosophy of science movement: Carl Hempel, Patrick Suppes, David Bohm, Hilary Putnam, Thomas Kuhn, and Dudley Shapere, among others. Especially noteworthy are Suppe’s account of the development of the Received View and the criticisms that have been lodged against it, viz., its reliance on the analytic-synthetic distinction; the tenability of the observational-theoretical distinction; the notion of partial interpretation; its failure to include models as integral components; its analysis of correspondence rules; and its reliance on axiomatization. Suppe also details some of the proposed alternatives to the Received View, giving in the process lucid expositions of the thought of Toulmin, Kuhn, Hanson, Popper, and Feyerabend—all of which he treats under the rubric of "Weltanshauungen [[sic]] Analyses." Those interested in the relationships between history of science and philosophy of science will find the interchange between I. Bernard Cohen and Peter Achinstein stimulating as well as illuminating. Kuhn takes this occasion to offer his "Second Thoughts on Paradigms," and Shapere continues his criticism of both Kuhn and logical positivism—now more constructively than heretofore—with a penetrating essay entitled "Scientific Theories and their Domains." About the only thing that is lacking is a treatment of recent developments in England, particularly the work of Rom Harré at Oxford and related thinkers, who likewise reject the Received View and offer interesting alternatives to it that have yet to be appreciated and critiqued in the U.S.—W.A.W. (shrink)

What is spacetime? General relativity and quantum field theory answer this question in very different ways. This collection of essays by physicists and philosophers looks at the problem of uniting these two most fundamental theories of our world, focusing on the nature of space and time within this new quantum framework, and the kind of metaphysical picture suggested by recent developments in physics and mathematics. This is a book that will inspire further philosophical reflection on recent advances in modern physics.

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)

Structural realism à-la-Worrall is the view that inasmuch as our scientific theories provide us with (partially) adequate descriptions of an objective and independent reality, they do so by shedding light on the way this reality is in itself structured, and not on the so-called nature of existing objects. This position seems to imply that there is something about reality that lies beyond our grasp. I will reconstruct and shed new light onto Worrall’s position and show that, contrary to how it (...) might appear at first sight, its allegedly negative, or pessimist stance has a positive side: by placing a constraint on our (theoretically mediated) knowledge, structural realism might tell us something relevant about the nature and functioning of our scientific understanding of the world. The paper is divided in three parts. The first part is devoted to a brief reconstruction of Worrall’s position. In the second part, I propose a new reading of the position in question by uncovering, highlighting and developing its epistemological consequences. In the last part, I investigate and scrutinize the connection between understanding and structures. The overall aim is to show how Worrall’s structural realism, especially in the reading I am proposing here, may provide us with a plausible explanation of the epistemic value of past and actual scientific theories. (shrink)

In the last decade, structural realism has been presented as the most promising strategy for developing a defensible realist view of science. Nevertheless, controversy still continues in relation to the exact meaning of the proposed structuralism. The stronger version of structural realism, the so-called ontic structural realism, has been argued for on the basis of some ideas related to quantum mechanics. In this paper, I will first outline these arguments, mainly developed by Steven French and James Ladyman, then challenge them, (...) putting a particular emphasis on a metaphysical principle which, even though it is crucial for the whole argument, hasn't been, in my opinion, clearly stated and examined yet. My overall view will be that a weaker version of the form of realism we are considering is more plausible – namely, epistemic structural realism. (shrink)

In this paper we adopt a category-theoretic viewpoint in order to analyze the semantics of complementarity for quantum systems. Based on the existence of a pair of adjoint functors between the topos of presheaves of the Boolean kind of structure and the category of the quantum kind of structure, we establish a twofold complementarity scheme which constitutes an instance of the concept of adjunction. It is further argued that the established scheme is inextricably connected with a realistic philosophical attitude, although (...) substantially different from the classical one. (shrink)

This paper argues that scientific realism commits us to a metaphysical determination relation between the mathematical entities that are indispensible to scientific explanation and the modal structure of the empirical phenomena those entities explain. The argument presupposes that scientific realism commits us to the indispensability argument. The viewpresented here is that the indispensability of mathematics commits us not only to the existence of mathematical structures and entities but to a metaphysical determination relation between those entities and the modal structure of (...) the physical world. The no-miracles argument is the primary motivation for scientific realism. It is a presupposition of this argument that unobservable entities are explanatory only when they determine the empirical phenomena they explain. I argue that mathematical entities should also be seen as explanatory only when they determine the empirical facts they explain, namely, the modal structure of the physical world. Thus, scientific realism commits us to a metaphysical determination relation between mathematics and physical modality that has not been previously recognized. The requirement to account for the metaphysical dependence of modal physical structure on mathematics limits the class of acceptable solutions to the applicability problem that are available to the scientific realist. (shrink)

In the pure powers ontology (PPO), basic physical properties have wholly dispositional essences. PPO has clear advantages over categoricalist ontologies, which suffer from familiar epistemological and metaphysical problems. However, opponents argue that because it contains no qualitative properties, PPO lacks the resources to individuate powers, and generates a regress. The challenge for those who take such arguments seriously is to introduce qualitative properties without reintroducing the problems that PPO was meant to solve. In this paper, I distinguish the core claim (...) of PPO: (i) basic physical properties have dispositional essences, from a hitherto unnoticed assumption: (ii) the dispositional essences of basic physical properties exclusively involve type-causal relations to other basic physical properties. I reject (ii), making room for a structuralist ontology in which all basic physical properties are pure powers, individuated by their places in a causal structure that includes not only other powers, but also physically realized qualitative properties such as shapes, patterns and structures. Such qualities individuate pure powers in the way that non-mental input and output properties individuate realized mental properties in functionalist theories of mind, except that here it is basic physical powers that are individuated by relations to realized non-powers. I distinguish one Platonic and two Aristotelian version of this theory, and argue that the Aristotelian versions require that grounding is not always a relative fundamentality relation, because the powers ground the qualities that individuate them. By considering ontic structural realism, I argue that symmetric grounding is the best way to make sense of relational individuation in structuralist ontologies, and is therefore no additional commitment of the one proposed here. (shrink)

The argument is directed at the view that scientific knowledge is just knowledge of the structure of the natural world and not knowledge of its intrinsic nature. The origin of the view is the post-Galilean conception of modern science, which views science as yielding a picture of nature stripped of all color, explaining all physical processes purely in terms of space-time, particles, fields, forces and the like, the intrinsic natures of which are never themselves analyzed. It is safe to say (...) that this conception of the limits of scientific knowledge, i.e. of its purely mathematical and structural character, is still a dominant one for both philosophers and scientists. (shrink)

James Ladyman and Don Ross, with David Spurrett and John Collier, Every Thing Must Go: Metaphysics Naturalized. Oxford University Press 2007 x+346 Philosophical Papers Vol. 37 2008: pp. 333-336.

In my review of Steven French's The structure of the world. Metaphysics & Representation. OUP, Oxford, 2014 I argue that the author is forced to navigate between the Scilla of Tegmark’s Pitagoreanism (2008) and the Carybdis of “blobobjectivism” (Horgan and Potrč 2008), namely the claim that the whole physical universe is a single concrete structurally complex but partless cosmos (a “blob”).

Within the standard structuralist approach, the theoretical description of a system by means of an empirical theory T is regarded as an extension process in which partial models are extended into models of T by supplementing suitable T-theoretical functions. Thereby, it is taken for granted that the base sets, on which these functions or relations are defined, can be assumed as given independently of the theory in question. My aim in this paper is to show that, in many cases, this (...) assumption is not justified. I will argue that this fact—which may be seen as a mere technical complication on first sight—turns out to have profound consequences for core concepts of the structuralist framework: First, the concept of intended applications has to be reconsidered. Second, the extension process has to be described in a more differentiated and complex way. Third, the theory-dependent determination of base sets has major implications concerning the defense mechanisms of empirical theories against conflicting observational data. (shrink)

We argue that the economy of nature constitutes an invocation of structure in the biological sciences, one largely missed by philosophers of biology despite the turn in recent years toward structural explanations throughout the philosophy of science. We trace a portion of the history of this concept, beginning with the theologically and economically grounded work of Linnaeus, moving through Darwin’s adaptation of the economy of nature and its reconstitution in genetic terms during the first decades of the Modern Synthesis. What (...) this historical case study reveals, we argue, is a window into the shifting landscape of the explanatory and ontic uses of structural concepts. In Linnaeus, the economy of nature has both ontic and explanatory import; in Darwin the ontic and explanatory aspects start to come apart ; and finally, in the Modern Synthesis, the economy of nature is replaced by the conceptual toolkit of population genetics, the structural elements of which are nearly entirely explanatory. Having traced a historical trajectory of structural concepts that moves from an ontic formulation to an increasingly explanatory one, we conclude by outlining some insights for structural realism. (shrink)

Le réalisme structural est une tentative d’établir un compromis entre le réalisme scientifique et l’empirisme, en restreignant le réalisme à la structure relationnelle des théories scientifiques. Il se décline en deux versions, épistémique et ontique. Le réalisme structural ontique propose de concevoir les relations nomologiques décrites par les théories comme des éléments primitifs de la réalité. Il est motivé, notamment, par le fait que sous sa forme épistémique, le réalisme structural ne se distingue pas réellement d’une position empiriste. Cependant, il (...) fait face à des difficultés, en particulier pour différencier relations physiques et mathématiques et rendre compte de l’ancrage expérimental des théories. Il est possible d’établir un parallèle entre ces difficultés et le problème de la mesure en mécanique quantique, qui concerne lui aussi les rapports entre modèle théorique et expérience : on constate alors qu’un réalisme structural épistémique est plus à même d’y répondre. Une solution de compromis entre le réalisme structural ontique et le réalisme structural épistémique pourrait permettre de conserver les avantages des deux positions. -/- Structural realism attempts to make a compromise between scientific realism and empiricism, by restricting our realist commitment to the relational structure of scientific theories. There are two main versions of the position: ontic, or epistemic. According to ontic structural realism, the nomological relations expressed by theories are the primitive entities of reality. This ontic version is motivated in particular by arguments to the effect that epistemic versions are not really distinct from mere empiricism. However according to some authors, it’s not clear that ontic structural realism can differentiate between physical and mathematical relations, and account for the relations between scientific theories and their experimental basis. These difficulties can be related to the measurement problem in quantum mechanics, which also concerns the link between theoretical models and experiments. It appears that epistemic structural realism is in a better position to respond to these difficulties. A compromise between both versions of structural realism could allow us to keep the advantages of both. (shrink)

Entrée encyclopédique / Encyclopedia Entry.

In this paper I discuss the Newman problem in the context of contemporary epistemic structural realism (ESR). I formulate Newman’s objection in terms that apply to today’s ESR and then evaluate a defence of ESR based on Carnap’s use of Ramsey sentences and Hilbert’s ε-operator. I show that this defence improves the situation by allowing a formal stipulation of non-structural constraints. However, it fails short of achieving object individuation in the context of satisfying the Ramsified form of a theory. Thus, (...) while limiting the scope of Newman’s argument, Carnap sentences do not fully solve the problem. (shrink)

We examine recent work in cognitive neuroscience that investigates brain networks. Brain networks are characterized by the ways in which brain regions are functionally and anatomically connected to one another. Cognitive neuroscientists use various noninvasive techniques (e.g., fMRI) to investigate these networks. They represent them formally as graphs. And they use various graph theoretic techniques to analyze them further. We distinguish between knowledge of the graph theoretic structure of such networks (structural knowledge) and knowledge of what instantiates that structure (nonstructural (...) knowledge). And we argue that this work provides structural knowledge of brain networks. We explore the significance of this conclusion for the scientific realism debate. We argue that our conclusion should not be understood as an instance of a global structural realist claim regarding the structure of the unobservable part of the world, but instead, as a local structural realist attitude towards brain networks in particular. And we argue that various local approaches to the realism debate, i.e., approaches that restrict realist commitments to particular theories and/or entities, are problematic insofar as they don't allow for the possibility of such a local structural realist attitude. (shrink)

When scientists put forward hypotheses, they sometimes involve new kinds of entities, which we can call 'hypothetical entities.' Hypothetical entities are pervasive in the sciences, and some examples include caloric and, up until very recently, the Higgs boson. Some hypothetical entities are discovered, as was the case with the Higgs boson, while scientists conclude that others, like caloric, do not exist. Hypothetical entities pose a number of important challenges for the philosophy of science, and my goal is to develop and (...) defend what I will call the suppositionalist view of hypothetical entities. In chapter 1, I examine the extant views of hypothetical entities, which I draw from the scientific realism debate. I argue that these views are all committed to the claim that terms for hypothetical entities putatively refer to empirical entities. In chapter 2, I develop the suppositionalist view of hypothetical entities. On this view, terms for hypothetical entities refer to what are called 'objects of supposition.' Examples of such objects from other domains include fictional characters like Superman and mathematical objects like the natural numbers. I draw from analogies with fiction and mathematics in order to develop the suppositionalist view in the scientific domain. In chapter 3, I give a history of a hypothetical entity that I will later use as a test case for views of hypothetical entities. In the late-eighteenth century, Antoine Lavoisier hypothesized that muriatic acid is composed of oxygen and a hypothetical entity called the 'muriatic radical.' In the early-nineteenth century, Humphry Davy's work on muriatic acid showed that it is actually composed of hydrogen and chlorine, and so muriatic acid is hydrochloric acid. Finally, in chapter 4, I use the history of the muriatic radical in order to argue against the extant views, and for the suppositionalist view. I argue that the former are committed to giving a history of the muriatic radical that is either whiggish or incomplete. The latter, however, can give us a non-whiggish history that is more complete, and hence it is preferable to the extant views. (shrink)

In the debate of scientific realism, the argument from underdetermination of theories by evidence is put forward by the anti-realist side. According to this argument, for any scientific theory rival theories can be found which are equally well supported by the evidence but incompatible with the original theory. Structural realism is a form of realism that limits the realistic belief in the existence of the entities and structures talked about in scientific theories: Only the structures of reality are relevant in (...) an epistemic sense and responsible for the truth and falsehood of theories. In the light of the antirealistic arguments, structural realism is supposed to have clear advantages over other varieties of scientific realism. In particular, Worrall ([21]) argues that structural realism is immune against the argument from underdetermination. I will sketch Worrall’s line of argument in a more systematic manner and conclude that it is based on some problematic preconditions. (shrink)

Fundamental physics contains an important link between properties of elementary particles and continuous symmetries of particle systems. For example, properties such as mass and spin are said to be 'associated' with specific continuous symmetries. -/- These 'associations' have played a key role in the discovery of various new particle kinds, but more importantly: they are thought to provide a deep insight into the nature of physical reality. The link between properties and symmetries has been said to call for a radical (...) revision of perceived metaphysical orthodoxy. However, if we are to use claims about an 'association' between properties and symmetries in the articulation of metaphysical views, we first need to develop a sufficiently precise understanding of the content of these claims. The goal of this paper is to do just that. (shrink)

Any successful account of the metaphysics of mechanistic causation must satisfy at least five key desiderata. In this paper, I lay out these five desiderata and explain why existing accounts of the metaphysics of mechanistic causation fail to satisfy them. I then present an alternative account which does satisfy the five desiderata. According to this alternative account, we must resort to a type of ontological entity that is new to metaphysics, but not to science: constraints. In this paper, I explain (...) how a constraints-based metaphysics fits best with the emerging consensus on the nature of mechanistic explanation. (shrink)

The main purpose of this paper is to test structural realism against (one example from) the historical record. I begin by laying out an existing challenge to structural realism -- that of providing an example of a theory exhibiting successful structures that were abandoned -- and show that this challenge can be met by the miasma theory of disease. However, rather than concluding that this is an outright counterexample to structural realism, I use this case to show why it is (...) that structural realism, in its current form, has trouble dealing with theories outside physics. I end by making some concrete suggestions for structural realists to pursue if, indeed, they are serious about extending structural realism to other domains. (shrink)

Howard argues that the existence of unitarily inequivalent representations in Quantum Field Theory presents a problem for structural realism in this context. I consider two potential ways round this problem: 1), follow Wallace in adopting the 'naive' Lagrangian form of QFT with cut-offs; 2), adapt Ruetsche's 'Swiss Army Knife' approach. The first takes us into the current debate between Wallace and Fraser on conventional vs. algebraic QFT. The second involves consideration of the role of inequivalent representations in understanding spontaneous symmetry (...) breaking and quantum statistics. In both cases, I suggest, the structural realist has sufficient room to manoeuvre. (shrink)

The intuition of the naı¨ve realist, miracle arguments notwithstanding, is countered forcefully by a host of considerations, including the possibility of underdetermination, and criticisms of abductive inferences to explanatory hypotheses. Some have suggested that an induction may be performed, from the perspective of present theories, on their predecessors. Past theories are thought to be false, strictly speaking; it is thus likely that present-day theories are also false, and will be taken as such at an appropriate future time.

In the 20th century the infiltration of scientific elements into philosophical currents not only reached its maximum, but also science itself became a "philosophical factor". We look at these processes in physics starting from the fall of mechanistic philosophy. The advent of relativity theory and quantum mechanics has changed physics as science and raised a host of philosophical questions. Traditionally philosophical questions concerning space, time and causality cannot be any longer considered with no help of these theories. Relativistic cosmology and (...) its observational successes in the last decades of the century, for the first time in the history of human thought, provided a global framework for both science and philosophy. And the current search for the final unifying theory of physics leads directly to the most foundational questions of an ontological character. We argue that the success of the 20th century physics strongly suggests a kind of structuralist ontology. /// No século XX, a infiltração de elementos científicos nas correntes filosóficas não só alcançou o seu máximo, mas também é verdade que a própria ciência se tornou um "factor filosófico". O presente artigo considera estes processos na física, a começar com a decadência da filosofia mecanicista. O advento da teoria da relatividade e da mecânica quântica transformou a física enquanto ciência e levantou uma plêiade de questões filosóficas. Questões tradicionais acerca do espaço, do tempo e da causalidade não podem mais ser consideradas sem o contributo destas teorias. A cosmologia relati-vista e os seus sucessos observacionais nas últimas décadas do século passado, e isso pela primeira vez na história do pensamento humano, fornecem um esquema global tanto para a ciência como para a filosofia. Além disso, a busca corrente de uma última teoria unificadora da física conduz directamente às questões mais fundacionais de carácter ontológico. O autor do artigo defende que os sucessos da física do século XX sugerem fortemente uma espécie de ontologia estruturalista. (shrink)

Ontic structural realism (OSR) claims that all there is to the world is structure. But how can this slogan be turned into a worked-out metaphysics? Here I consider one potential answer: a metaphysical framework known as generalism (Dasgupta, 2009, 2016). According to the generalist, the most fundamental description of the world is not given in terms of individuals bearing properties, but rather, general facts about which states of affairs obtain. However, I contend that despite several apparent similarities between the positions, (...) generalism is unable to capture the two main motivations for OSR. I suggest instead that OSR should be construed as a meta-metaphysical position. (shrink)

In this paper I elicit a prediction from structural realism and compare it, not to a historical case, but to a contemporary scientific theory. If structural realism is correct, then we should expect physics to develop theories that fail to provide an ontology of the sort sought by traditional realists. If structure alone is responsible for instrumental success, we should expect surplus ontology to be eliminated. Quantum field theory (QFT) provides the framework for some of the best confirmed theories in (...) science, but debates over its ontology are vexed. Rather than taking a stand on these matters, the structural realist can embrace QFT as an example of just the kind of theory SR should lead us to expect. Yet, it is not clear that QFT meets the structuralist's positive expectation by providing a structure for the world. In particular, the problem of unitarily inequivalent representations threatens to undermine the possibility of QFT providing a unique structure for the world. In response to this problem, I suggest that the structuralist should endorse pluralism about structure. (shrink)

The ways in which space-time points and elementary particles are modeled share a curious feature: neither seems to specify which basic object has which properties. This chapter sketches the motivation for this claim and searches for an explanation for it. After reviewing several proposals, it argues for a view according to which objects occupy their place in a given relational structure essentially. This view, which is termed minimal structural essentialism, provides a metaphysical grounding for the physical equivalence of models related (...) by permutation. An interesting consequence of this position is that space-time points and elemental particles turn out to be individuals, albeit of a rather different sort than has traditionally been considered. (shrink)

Structural realists claim that we should endorse only what our scientific theories say about the structure of the unobservable world. But according to Newman’s Objection, the structural realist’s claims about unobservables are trivially true. In recent years, several theorists have offered responses to Newman’s Objection. But a common complaint is that these responses “give up the spirit” of the structural realist position. In this paper, I will argue that the simplest way to respond to Newman’s Objection is to return to (...) one of the standard motivations for adopting structural realism in the first place: the No Miracles Argument. Far from betraying the spirit of structural realism, the solution I present is available to any theorist who endorses this argument. (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 the present paper the attempt is made for the first time to formalize the modern theory of elementary particles based on the structuralist approach. To this end, the description within the scope of the so-called standard model is considered. In the physics of elementary particles the term ‘standard model’ denotes the summary of theories which describe the various elementary building blocks of matter as well as their interactions between each other. This model represents one of the most successful theories (...) in physics, particularly because of the impressive experimental confirmation. Hence a structuralist reconstruction of it is a challenging task. (shrink)