Everything you always wanted to know about structural realism but were afraid to ask Content Type Journal Article Pages 227-276 DOI 10.1007/s13194-011-0025-7 Authors Roman Frigg, Department of Philosophy, Logic and Scientific Method, London School of Economics and Political Science, Houghton Street, London, WC2A 2AE UK Ioannis Votsis, Philosophisches Institut, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, Geb. 23.21/04.86, 40225 Düsseldorf, Germany Journal European Journal for Philosophy of Science Online ISSN 1879-4920 Print ISSN 1879-4912 Journal Volume Volume 1 Journal Issue Volume 1, Number 2.

he relationship between metaphysics and science has recently become the focus of increased attention. Ladyman and Ross, in particular, have accused even naturalistically inclined metaphysicians of pursuing little more than the philosophy of A-level chemistry and have suggested that analytic metaphysics should simply be discontinued. In contrast, we shall argue, first of all, that even metaphysics that is disengaged from modern science may offer a set of resources that can be appropriated by philosophers of physics in order to set physics (...) within an interpretational framework. Secondly, however, we shall urge that insofar as metaphysics is intended to be more than just a toolbox it needs to accommodate the implications of physics if many of its core claims are to be sustained. We shall illustrate this last point with a discussion of the nature of laws and modality in the context of modern physics. (shrink)

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

The Newman problem is a fundamental problem that threatens to undermine structural assumptions and structural theories throughout philosophy and science. Here, we consider the problem in the context of consciousness science. We introduce and discuss the problem, and explain why it is detrimental not only to structuralist assumptions, but also to theories of consciousness, if left unconsidered. However, we show that if phenomenal spaces, and mathematical structures of conscious experience more generally, are understood in the right way, the Newman problem (...) does not arise. The upshot of our paper is that consciousness science needs to be careful in which definition of structure to consider, but if it is, the Newman problem disappears. (shrink)

Within the philosophy of science, the realism debate has been revitalised by the development of forms of structural realism. These urge a shift in focus from the object oriented ontologies that come and go through the history of science to the structures that remain through theory change. Such views have typically been elaborated in the context of theories of physics and are motivated by, first of all, the presence within such theories of mathematical equations that allow straightforward representation of the (...) relevant structures; and secondly, the implications of such theories for the individuality and identity of putative objects. My aim in this talk is to explore the possibility of extending such views to biological theories. An obvious concern is that within the context of the latter it is typically insisted that we cannot find the kinds of highly mathematised structures that structural realism can point to in physics. I shall indicate how the model-theoretic approach to theories might help allay such concerns. Furthermore, issues of identity and individuality also arise within biology. Thus Dupre has recently noted that there exists a ‘General Problem of Biological Individuality’ which relates to the issue of how one divides ‘massively integrated and interconnected’ systems into discrete components. In response Dupre advocates a form of ‘Promiscuous Realism’ that holds, for example, that there is no unique way of dividing the phylogenetic tree into kinds. Instead I shall urge serious consideration of those aspects of the work of Dupre and others that lean towards a structuralist interpretation. By doing so I hope to suggest possible ways in which a structuralist stance might be extended to biology. (shrink)

Recent work in the philosophy of science has generated an apparent conflict between theories attempting to explicate the nature of scientific representation. On one side, there are what one might call 'informational' views, which emphasize objective relations (such as similarity, isomorphism, and homomorphism) between representations (theories, models, simulations, diagrams, etc.) and their target systems. On the other side, there are what one might call 'functional' views, which emphasize cognitive activities performed in connection with these targets, such as interpretation and inference. (...) The main sources of the impression of conflict here are arguments by some functionalists to the effect that informational theories are flawed: it is suggested that relations typically championed by informational theories are neither necessary nor sufficient for scientific representation, and that any theory excluding functions is inadequate. In this paper I critically examine these arguments, and contend that, as it turns out, informational and functional theories are importantly complementary. (shrink)

This paper is a review of work on Newman's objection to epistemic structural realism (ESR). In Section 2, a brief statement of ESR is provided. In Section 3, Newman's objection and its recent variants are outlined. In Section 4, two responses that argue that the objection can be evaded by abandoning the Ramsey-sentence approach to ESR are considered. In Section 5, three responses that have been put forward specifically to rescue the Ramsey-sentence approach to ESR from the modern versions of (...) the objection are discussed. Finally, in Section 6, three responses are considered that are neutral with respect to one's approach to ESR and all argue (in different ways) that the objection can be evaded by introducing the notion that some relations/structures are privileged over others. It is concluded that none of these suggestions is an adequate response to Newman's objection, which therefore remains a serious problem for ESRists. Introduction Epistemic Structural Realism 2.1 Ramsey-sentences and ESR 2.2 WESR and SESR The Objection 3.1 Newman's version 3.2 Demopoulos and Friedman's and Ketland's versions Replies that Abandon the Ramsey-Sentence Approach to ESR 4.1 Redhead's reply 4.2 French and Ladyman's reply Replies Designed to Rescue the Ramsey-Sentence Approach 5.1 Zahar's reply 5.2 Cruse's reply 5.3 Melia and Saatsi's reply Replies that Argue that Some Structures/Relations are Privileged 6.1 A Carnapian reply 6.2 Votsis' reply 6.3 The Merrill/Lewis/Psillos reply Summary CiteULike Connotea Del.icio.us What's this? (shrink)

I review the philosophical literature on the question of when two physical theories are equivalent. This includes a discussion of empirical equivalence, which is often taken to be necessary, and sometimes taken to be sufficient, for theoretical equivalence; and “interpretational” equivalence, which is the idea that two theories are equivalent just in case they have the same interpretation. It also includes a discussion of several formal notions of equivalence that have been considered in the recent philosophical literature, including (generalized) definitional (...) equivalence and categorical equivalence. The article concludes with a brief discussion of the relationship between equivalence and duality. The article is in two parts; this is Part 1, which addresses empirical equivalence and definitional equivalence. (shrink)

The central concern of this article is whether the semantic approach has the resources to appropriately capture the core tenets of structural realism. Chakravartty (2001) has argued that a realist notion of correspondence cannot be accommodated without introducing a linguistic component, which undermines the approach itself. We suggest that this worry can be addressed by an appropriate understanding of the role of language in this context. The real challenge, however, is how to incorporate the core notion of `explanatory approximate truth' (...) in such a way that the emphasis on structure is retained. (shrink)

I review the philosophical literature on the question of when two physical theories are equivalent. This includes a discussion of empirical equivalence, which is often taken to be necessary, and sometimes taken to be sufficient, for theoretical equivalence; and “interpretational” equivalence, which is the idea that two theories are equivalent just in case they have the same interpretation. It also includes a discussion of several formal notions of equivalence that have been considered in the recent philosophical literature, including (generalized) definitional (...) equivalence and categorical equivalence. The article concludes with a brief discussion of the relationship between equivalence and duality. The article is in two parts; this is Part 2, which addresses categorical equivalence, interpretational equivalence, and duality. (shrink)

‘Epistemic structural realism’ (ESR) insists that all that we know of the world is its structure, and that the ‘nature’ of the underlying elements remains hidden. With structure represented via Ramsey sentences, the question arises as to how ‘hidden natures’ might also be represented. If the Ramsey sentence describes a class of realisers for the relevant theory, one way of answering this question is through the notion of multiple realisability. We explore this answer in the context of the work of (...) Carnap, Hintikka and Lewis. Both Carnap and Hintikka offer clear structuralist perspectives which, crucially, accommodate the openness inherent in theory change. Unfortunately there is little purchase for a viable form of realism in either case. Lewis’s approach, on the other hand, offers more scope for realism but, as we shall see, concerns arise as to whether a relevant form of structuralism can be maintained. In particular his thesis of Ramseyan humility undermines certain conceptions of scientific laws that the structural realist might naturally cleave to. Our overall conclusion is that the representational device of Ramsey sentence plus multiple realisability can accommodate either the structuralist or realist aspects of ESR but has difficulties capturing both. (shrink)

Structural realists of nearly all stripes endorse the structural continuity claim. Roughly speaking, this is the claim that the structure of successful scientific theories survives theory change because it has latched on to the structure of the world. In this paper I elaborate, elucidate and modify the structural continuity claim and its associated argument. I do so without presupposing a particular conception of structure that favours this or that kind of structural realism. Instead I focus on how structural realists can (...) best account for the neutrally formulated historical facts. The result, I hope, crystallises some of the shared commitments, desiderata and limits of structural realists. (shrink)

This article develops an analogy proposed by Stachel between general relativity (GR) and quantum mechanics (QM) as regards permutation invariance. Our main idea is to overcome Pooley's criticism of the analogy by appeal to paraparticles. In GR, the equations are (the solution space is) invariant under diffeomorphisms permuting spacetime points. Similarly, in QM the equations are invariant under particle permutations. Stachel argued that this feature—a theory's ‘not caring which point, or particle, is which’—supported a structuralist ontology. Pooley criticizes this analogy: (...) in QM the (anti-)symmetrization of fermions and bosons implies that each individual state (solution) is fixed by each permutation, while in GR a diffeomorphism yields in general a distinct, albeit isomorphic, solution. We define various versions of structuralism, and go on to formulate Stachel's and Pooley's positions, admittedly in our own terms. We then reply to Pooley. Though he is right about fermions and bosons, QM equally allows more general types of particle symmetry, in which states (vectors, rays, or density operators) are not fixed by all permutations (called ‘paraparticle states’). Thus Stachel's analogy is revived. (shrink)

David Lewis (1941–2001) was one of the most important philosophers of the 20th Century. He made significant contributions to philosophy of language, philosophy of mathematics, philosophy of science, decision theory, epistemology, meta-ethics and aesthetics. In most of these fields he is essential reading; in many of them he is among the most important figures of recent decades. And this list leaves out his two most significant contributions. -/- In philosophy of mind, Lewis developed and defended at length a new version (...) of materialism (see the entry on physicalism). He started by showing how the motivations driving the identity theory of mind and functionalism could be reconciled in his theory of mind. He called this an identity theory, though his theory motivated the position now known as analytic functionalism. And he developed detailed accounts of mental content (building on Davidson’s interpretationism) and phenomenal knowledge (building on Nemirow’s ability hypothesis) that are consistent with his materialism. The synthesis Lewis ended up with is one of the central positions in contemporary debates in philosophy of mind. -/- But his largest contributions were in metaphysics. One branch of his metaphysics was his Hume-inspired reductionism about the nomological. He developed a position he called “Humean supervenience”, the theory that said that there was nothing to reality except the spatio-temporal distribution of local natural properties. And he did this by showing in detail how laws, chances, counterfactual dependence, causation, dispositions and colours could be located within this Humean mosaic. The other branch of his metaphysics was his modal realism. Lewis held that the best theory of modality posited concrete possible worlds. A proposition is possible if and only if it is true at one of these worlds. Lewis defended this view in his most significant book, On the Plurality of Worlds. Alongside this, Lewis developed a new account of how to think about modal properties of individuals, namely counterpart theory, and showed how this theory resolved several long-standing puzzles about modal properties. (shrink)

I review the philosophical literature on the question of when two physical theories are equivalent. This includes a discussion of empirical equivalence, which is often taken to be necessary, and sometimes taken to be sufficient, for theoretical equivalence; and "interpretational" equivalence, which is the idea that two theories are equivalent just in case they have the same interpretation. It also includes a discussion of several formal notions of equivalence that have been considered in the recent philosophical literature, including definitional equivalence (...) and categorical equivalence. The article concludes with a brief discussion of the relationship between equivalence and duality. (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)

In the literature over the Ramsey-sentence approach to structural realism, there is often debate over whether structural realists can legitimately restrict the range of the second-order quantifiers, in order to avoid the Newman problem. In this paper, I argue that even if they are allowed to, it won’t help: even if the Ramsey sentence is interpreted using such restricted quantifiers, it is still an implausible candidate to capture a theory’s structural content. To do so, I use the following observation: if (...) a Ramsey sentence did encode a theory’s structural content, then two theories would be structurally equivalent just in case they have logically equivalent Ramsey sentences. I then argue that this criterion for structural equivalence is implausible, even where frame or Henkin semantics are used. (shrink)

In this paper we argue that quantum mechanics provides a genuine kind of structural explanations of quantum phenomena. Since structural explanations only rely on the formal properties of the theory, they have the advantage of being independent of interpretative questions. As such, they can be used to claim that, even in the current absence of one agreed-upon interpretation, quantum mechanics is capable of providing satisfactory explanations of physical phenomena. While our proposal clearly cannot be taken to solve all interpretive issues (...) raised by quantum theory, we will argue that it can be successfully applied to some of its most puzzling phenomena, such Heisenberg's uncertainty relations and quantum non-locality. The discussion of these two case studies will also serve to illustrate the main properties of structural explanations and compare them to the DN and the unificationist models. Finally, we briefly discuss how structural explanations might relate to structural realism. (shrink)

Structural realism was born in the attempt to reach a compromise between a realist argument and an antirealist one, namely the ‘no miracle’ ­argument and the ‘pessimistic meta-induction’, respectively. According to the ‘no miracle’ argument, scientific realism is the only philosophy that does not make the success of science a miracle. The only way of explaining why science is so ­successful in making predictions that most of the time turn out to be verified, is to believe that theoretical terms refer, (...) that theories in mature science are true or at least approximately true, and that the same term refers to the same thing even if it occurs in different theories. It is the referential nature of scientific theories that explains the success of science. (shrink)

Starting from the sixties of the past century theory change has become a main concern of philosophy of science. Two of the best known formal accounts of theory change are the post-Popperian theories of verisimilitude (PPV for short) and the AGM theory of belief change (AGM for short). In this paper, we will investigate the conceptual relations between PPV and AGM and, in particular, we will ask whether the AGM rules for theory change are effective means for approaching the truth, (...) i.e., for achieving the cognitive aim of science pointed out by PPV. First, the key ideas of PPV and AGM and their application to a particular kind of propositional theories - the so called "conjunctive propositions" - will be illustrated. Afterwards, we will prove that, as far as conjunctive propositions are concerned, AGM belief change is an effective tool for approaching the truth. (shrink)

An argument, different from the Newman objection, against the view that the cognitive content of a theory is exhausted by its Ramsey sentence is reviewed. The crux of the argument is that Ramsification may ruin inductive systematization between theory and observation. The argument also has some implications concerning the issue of underdetermination.

Among scientific realists and anti-realists, there is a well-known, perennial dispute about the reality and knowability of unobservable objects. This dispute is also present among structural realists, who all agree that science gives us genuine knowledge of structure at the unobservable level (however that structure may be understood). Ontic structural realists reduce or eliminate the ontological role of objects, while epistemic structural realists argue that objects do or might exist but are unknowable. In part because ontic structural realism has some (...) evidence from quantum mechanics and the consequent underdetermination of the metaphysics of objects in its favor, the majority of contemporary structural realists adopt that view. In contrast, I argue that epistemic structural realism is a highly compelling view, particularly in the form that remains agnostic about unobservable objects. This view can remain consistent with the empirical data from quantum mechanics, can give a satisfactory account of the metaphysics of structure, and can distinguish itself from other extant versions of realism. I provide two arguments in favor of agnosticism about objects, the first of which argues that suspending belief is consistent with the impetus of naturalized metaphysics, and the second of which argues that agnosticism about objects is a rational response to reflection on the limits and aims of science. Thus, I show that agnostic epistemic structural realism is a defensible and compelling view in the philosophy of science that demands more attention in the literature. (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)

In what follows, I will give examples of the sorts of step that can be taken towards spelling out the intuition that, after all, good models might be true. Along the way, I provide an outline of my account of models as ontologically and pragmatically constrained representations. And I emphasize the importance of examining models as functionally composed systems in which different components play different roles and only some components serve as relevant truth bearers. This disputes the standard approach that (...) proceeds by simply counting true and false elements in models in their entirety and concludes that models are false since they contain so many false elements. I call my alternative the functional decomposition approach. (shrink)

This paper investigates whether there is an acceptable version of Functionalism that avoids commitment to second-order properties. I argue that the answer is "no". I consider two reductionist versions of Functionalism, and argue that both are compatible with multiple realization as such. There is a more specific type of multiple realization that poses difficulties for these views, however. The only apparent Functionalist solution is to accept second-order properties.

In this article I discuss a recent argument due to Dan McArthur, who suggests that the charge that Michael Friedman’s relativised a priori leads to irrationality in theory change can be avoided by adopting structural realism. I provide several arguments to show that the conjunction of Friedman’s relativised a priori with structural realism cannot make the former avoid the charge of irrationality. I also explore the extent to which Friedman’s view and structural realism are compatible, a presupposition of McArthur’s argument. (...) This compatibility is usually questioned, due to the Kantian aspect of Friedman’s view, which clashes with the metaphysical premise of scientific realism. I argue that structural realism does not necessarily depend on this premise and as a consequence can be compatible with Friedman’s view, but more importantly I question whether Friedman’s view really implies mind dependence. (shrink)

Funding policies for science are usually directed at supporting technological innovations. The im-pact and success of such policies depend crucially on how science and technology are connected to each other. I propose an “interactive view” of the relationship between basic science and technol-ogy development which comprises the following four claims: First, technological change derives from science but only in part. The local models used in accounting for technologically relevant phenomena contain theoretical and non-theoretical elements alike. Second, existing technologies and rules (...) of experience constitute another major repository of technological inventions. Third, technology dynamics is only weakly coupled to progress in basic science but it is closely related to science. There is a dependence of technological change on a more fundamental understanding, to be sure, but it is of an indirect and long-term character. Fourth, progress in basic research is some-times the effect of technological change. Technological change sometimes brings about increased theoretical understanding. (shrink)

Epistemic structural realists have argued that we are in a better epistemic position with respect to the structural claims made by our theories than the non-structural claims. Critics have objected that we cannot make the structure/non-structure distinction precise. I respond that a focus on mathematical structure leads to a clearer understanding of this debate. Unfortunately for the structural realist, however, the contribution that mathematics makes to scientific representation undermines any general confidence we might have in the structural claims made by (...) our theories. Thinking about the role of mathematics in science may also complicate other versions of realism. (shrink)

'Structural realism' is a buzzword in the scientific realism debate. Various positions with diverse motivations fall under this label. A much advertised distinction is between epistemic and ontological forms of structuralism. This paper scrutinizes the alleged dichotomy between these two 'alternatives', and criticises the considerations that have been taken to motivate the ontic variety over the epistemic. I will argue that ontological structural realism is not called for within the traditional realism debate.

Interpretation in science has gained little attention in the past because philosophers of science believed that interpretation belongs to the context of discovery or must be associated with meaning. But scientists often speak about interpretation when they report their findings. Elsewhere I have argue in favour of a pragmatic-rhetorical theory of explanation, and it is in light of this theory that I suggest we can understand interpretation in the natural sciences.

Structural realists claim that structure is preserved across instances of radical theory change, and that this preservation provides an argument in favor of realism about structure. In this paper, I use the shift from Newtonian gravity to Einstein’s general relativity as a case study for structural preservation, and I demonstrate that two prominent views of structural preservation fail to provide a solid basis for realism about structure. The case study demonstrates that (i) structural realists must be epistemically precise about the (...) concrete structure that is being preserved, and (ii) they must provide a metaphysical account of how structure is preserved through re-interpretation in light of a new theory. Regarding (i), I describe a means of epistemic access to the unobservable that I call “thick detection” of structure, which isolates the structure that will be preserved. Regarding (ii), I argue that thickly detectable structure is preserved across theory change through a process of extracting the old structure from the new structure, much like what has been done with geometrized versions of Newtonian gravity. With these two responses in hand, the structural realist can adequately account for the preservation of structure and can provide a strong argument in favor of structural realism. (shrink)

In this paper it is argued that the multiple realizability argument and Kripke's argument are based on schemas of identifications rather than identification. In fact, "heat = molecular motion" includes a term "molecular motion" that does not capture a natural kind, nor has a unique referent. If properly framed, this schema suits also for the type identity theory of mind. Some consequences of this point are evaluated.

Statistical inference is often justified by long-run properties of the sampling distributions, such as the repeated sampling rationale. These are frequentist justifications of statistical inference. I argue, in line with existing philosophical literature, but against a widespread image in empirical science, that these justifications are flawed. Then I propose a novel interpretation of probability in statistics, the artefactual interpretation. I believe that this interpretation is able to bridge the gap between statistical probability calculations and rational decisions on the basis of (...) observed data. The artefactual interpretation is able to justify statistical inference without making any assumptions about probability in the material world. (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)