Anjan Chakravartty

This paper explores the consequences of the two most prominent forms of contemporary structural realism for the notion of objecthood. Epistemic structuralists hold that we can know structural aspects of reality, but nothing about the natures of unobservable relata whose relations define structures. Ontic structuralists hold that we can know structural aspects of reality, and that there is nothing else to know—objects are useful heuristic posits, but are ultimately ontologically dispensable. I argue that structuralism does not succeed in ridding a structuralist ontology of objects.

Debates about scientific realism are closely connected to almost everything else in the philosophy of science, for they concern the very nature of scientific knowledge. Scientific realism is a positive epistemic attitude toward the content of our best theories and models, recommending belief in both observable and unobservable aspects of the world described by the sciences. This epistemic attitude has important metaphysical and semantic dimensions, and these various commitments are contested by a number of rival epistemologies of science, known collectively as forms of scientific antirealism. This article explains what scientific realism is, outlines its main variants, considers the most common arguments for and against the position, and contrasts it with its most important antirealist counterparts.

The semantic view of theoriesis one according to which theoriesare construed as models of their linguisticformulations. The implications of thisview for scientific realism have been little discussed. Contraryto the suggestion of various champions of the semantic view,it is argued that this approach does not makesupport for a plausible scientific realism anyless problematic than it might otherwise be.Though a degree of independence of theory fromlanguage may ensure safety frompitfalls associated with logical empiricism, realism cannot be entertained unless models or (abstractedand/or idealized) aspects thereof are spelled out in terms of linguistic formulations (such as mathematical equations),which can be interpreted in terms of correspondencewith the world. The putative advantage of thesemantic approach – its linguistic independence – isthus of no help to the realist. I consider recent treatmentsof the model-theoretic view (Suppe, Giere, Smith), and find that although some of these accounts harbour the promiseof realism, this promise is deceptive.

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

Debates about scientific realism are closely connected to almost everything else in the philosophy of science, for they concern the very nature of scientific knowledge. Scientific realism is a positive epistemic attitude toward the content of our best theories and models, recommending belief in both observable and unobservable aspects of the world described by the sciences. This epistemic attitude has important metaphysical and semantic dimensions, and these various commitments are contested by a number of rival epistemologies of science, known collectively as forms of scientific antirealism. This article explains what scientific realism is, outlines its main variants, considers the most common arguments for and against the position, and contrasts it with its most important antirealist counterparts.

Structural realism has recently re-entered mainstream discussions in the philosophy of science. The central notion of structure, however, is contested by both advocates and critics. This paper briefly reviews currently prominent structuralist accounts en route to proposing a metaphysics of structure that is capable of supporting the epistemic aspirations of realists, and that is immune to the charge most commonly levelled against structuralism. This account provides an alternative to the existing epistemic and ontic forms of the position, incorporating elements of both. Structures are here identified with relations between first order, causal properties: properties that confer specific dispositions for relations. This form of structuralism constitutes an explicit proposal for what seem implicit structuralist tendencies in sophisticated but more traditional characterizations of realism. An outline of the proposal's response to the anti-realist's pessimistic induction on the history of scientific theories is considered.

Minimally, causal realism (as understood here) is the view that accounts of causation in terms of mere, regular or probabilistic conjunction are unsatisfactory, and that causal phenomena are correctly associated with some form of de re necessity. Classic arguments, however, some of which date back to Sextus Empiricus and have appeared many times since, including famously in Russell, suggest that the very notion of causal realism is incoherent. In this paper I argue that if such objections seem compelling, it is only because everyday expressions concerning causal phenomena are misleading with respect to certain metaphysical details. These expressions generally make reference to the relations of events or states of affairs, but ignore or obscure the role played by causal properties. I argue that on a proposed alternative, an analysis in terms of causal processes, more refined descriptions of causal phenomena escape the charge of incoherence. Causal necessity is here located in the relations of causal properties. I distinguish this view from the recent process theories of Salmon and Dowe, which are disinterested in causal realism.

Two of the most potent challenges faced by scientific realism are the underdetermination of theories by data, and the pessimistic induction based on theories previously held to be true, but subsequently acknowledged as false. Recently, Stanford (2006, Exceeding our grasp: Science, history, and the problem of unconceived alternatives. Oxford: Oxford University Press) has formulated what he calls the problem of unconceived alternatives: a version of the underdetermination thesis combined with a historical argument of the same form as the pessimistic induction. In this paper, I contend that while Stanford does present a novel antirealist argument, a successful response to the pessimistic induction would likewise defuse the problem of unconceived alternatives, and that a more selective and sophisticated realism than that which he allows is arguably immune to both concerns.

One view of the nature of properties has been crystallized in recent debate by an identity thesis proposed by Shoemaker. The general idea is that there is for behaviour. Well-known criticisms of this approach, however, remain unanswered, and the details of its connections to laws nothing more to being a particular causal property than conferring certain dispositions of nature and the precise ontology of causal properties stand in need of development. This paper examines and defends a dispositional essentialist account of causal properties, combining a Shoemaker-type identity thesis with a Dretske, Tooley, and Armstrong-type view that laws are relations between properties, and a realism about dispositions. The property identity thesis is defended against standard epistemological and metaphysical objections. The metaphysics of causal properties is then clarified by a consideration of the laws relating them, vacuous laws, and ceteris paribus law statements.

Decades of debate about scientific realism notwithstanding, we find ourselves bemused by what different philosophers appear to think it is, exactly. Does it require any sort of belief in relation to scientific theories and, if so, what sort? Is it rather typified by a certain understanding of the rationality of such beliefs? In the following dialogue we explore these questions in hopes of clarifying some convictions about what scientific realism is, and what it could or should be. En route, we encounter some profoundly divergent conceptions of the nature of science and of philosophy.

In The empirical stance, Bas van Fraassen argues for a reconceptualization of empiricism, and a rejection of its traditional rival, speculative metaphysics, as part of a larger and provocative study in epistemology. Central to his account is the notion of voluntarism in epistemology, and a concomitant understanding of the nature of rationality. In this paper I give a critical assessment of these ideas, with the ultimate goal of clarifying the nature of debate between metaphysicians and empiricists, and more specifically, between scientific realists and empiricist antirealists. Despite van Fraassen’s assertion to the contrary, voluntarism leads to a form of epistemic relativism. Rather than stifling debate, however, this ‘stance’ relativism places precise constraints on possibilities for constructive engagement between metaphysicians and empiricists, and thus distinguishes, in broad terms, paths along which this debate may usefully proceed from routes which offer no hope of progress. Author Keywords: Empiricism; Metaphysics; Scientific realism; Voluntarism; Rationality; Relativism.

Scientific realism is the view that our best scientific theories give approximately true descriptions of both observable and unobservable aspects of a mind-independent world. Debates between realists and their critics are at the very heart of the philosophy of science. Anjan Chakravartty traces the contemporary evolution of realism by examining the most promising strategies adopted by its proponents in response to the forceful challenges of antirealist sceptics, resulting in a positive proposal for scientific realism today. He examines the core principles of the realist position, and sheds light on topics including the varieties of metaphysical commitment required, and the nature of the conflict between realism and its empiricist rivals. By illuminating the connections between realist interpretations of scientific knowledge and the metaphysical foundations supporting them, his book offers a compelling vision of how realism can provide an internally consistent and coherent account of scientific knowledge.

Realists regarding scientific knowledge – those who think that our best scientific representations truly describe both observable and unobservable aspects of the natural world – have special need of a notion of approximate truth. Since theories and models are rarely considered true simpliciter, the realist requires some means of making sense of the claim that they may be false and yet close to the truth, and increasingly so over time. In this paper, I suggest that traditional approaches to approximate truth are insensitive to two crucial features of scientific knowledge, and that for each of these, analogies between representational practices in the sciences and in art prove useful to understanding how this situation can be remedied. First, I outline two distinct ways in which representations deviate from the truth, commonly referred to as ‘abstraction’ and ‘idealization’. Second, I argue that these practices exemplify different conventions of representation, and that for each, the conditions of approximation relevant to explicating the concept of approximate truth must be understood differently. The concept is thus heterogeneous; approximate truth is a virtue that is multiply realized, relative to different contexts of representation. This understanding is facilitated, I suggest, by considering the distinction between realistic and non-realistic representation in art.

Scientific realism has three dimensions: a metaphysical commitment to the existence of a mind-independent world; a semantic commitment to a literal interpretation of scientific claims; and an epistemological commitment to scientific knowledge of both observable and unobservable entities. The semantic dimension is uncontroversial, and the epistemological dimension, though contested, is well articulated in a number of ways. The metaphysical dimension, however, is not even well articulated. In this paper, I elaborate a plausible understanding of mind independence for the realist – plausible in conceding the force of sceptical arguments to the effect that there is no one correct way to carve nature at its joints, but realist in proposing an objective basis for carving nonetheless. Walking this line between implausible realism and full-blown constructivism leads down the path of three forms of relativism or pluralism: one concerning the ways in which scientists “package” properties into entities; another concerning the precise metaphysical natures of these entities; and another concerning the context relativity of their behaviour

There is perhaps no more succinct a way of describing the controversy between scientific realists and antirealists than to say that it turns on the reality of the unobservable. Less concisely, it turns on whether we have reason to think that scientific theories tell us the truth (or something close to it) about some of the underlying, unobservable bits of a mind-independent, external reality, among other things. Claims to knowledge of such a reality have traditionally been a bone of contention between realists and empiricists. Two decades ago, this ongoing debate was inflamed by the introduction of Bas van Fraassen’s particular brand of empiricism. Wholesale idealists and phenomenalists have been increasingly marginalized. The reality of the observable is now generally taken for granted by most parties to the debate. The epistemic status of the unobservable, however, remains controversial.

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.

It is widely recognized that scientific theories are often associated with strictly inconsistent models, but there is little agreement concerning the epistemic consequences. Some argue that model inconsistency supports a strong perspectivism, according to which claims serving as interpretations of models are inevitably and irreducibly perspectival. Others argue that in at least some cases, inconsistent models can be unified as approximations to a theory with which they are associated, thus undermining this kind of perspectivism. I examine the arguments for perspectivism, and contend that its strong form is defeasible in principle, not merely in special cases. The argument rests on the plausibility of scientific knowledge concerning non-perspectival, dispositional facts about modelled systems. This forms the basis of a novel suggestion regarding how to understand the knowledge these models afford, in terms of a contrastive theory of what-questions.

The philosophy of science has produced numerous accounts of how scientific facts are generated, from very specific facilitators of belief, such as neo-Kantian constitutive principles, to global frameworks, such as Kuhnian paradigms. I consider a recent addition to this canon: van Fraassen’s notion of an epistemic stance—a collection of attitudes and policies governing the generation of factual beliefs—and his commitment to voluntarism in this context: the idea that contrary stances and sets of beliefs are rationally permissible. I argue that while scientific inquiry inevitably favours a high degree of consensus in our choices of stance, there is no parallel constraint in the case of philosophical inquiry, such as that concerned with how scientific knowledge should be interpreted. This leads, in the latter case, to a fundamental and apparently irresolvable mystery at the heart of stance voluntarism, regarding the grounds for choosing basic epistemic stances.

Decades of debate about scientific realism notwithstanding, we find ourselves bemused by what different philosophers appear to think it is, exactly. Does it require any sort of belief in relation to scientific theories and, if so, what sort? Is it rather typified by a certain understanding of the rationality of such beliefs? In the following dialogue we explore these questions in hopes of clarifying some convictions about what scientific realism is, and what it could or should be. En route, we encounter some profoundly divergent conceptions of the nature of science and of philosophy.

A Metaphysics for Scientific Realism: Knowing the Unobservable has two primary aims. The first is to extract the most promising refinements of the idea of scientific realism to emerge in recent decades and assemble them into a maximally defensible realist position, semirealism. The second is to demonstrate that, contra antirealist scepticism to the contrary, key concepts typically invoked by realists in expounding their views can be given a coherent and unified explication. These concepts include notions of causation, laws of nature, scientific kinds, and approximate truth, and consequently, the demonstration undertaken includes a metaphysical study of ideas more commonly employed unreflectively in epistemological assessments of the sciences. In this paper, I answer searching critiques of this project by Steven French, Michel Ghins, and Stathis Psillos

In the wake of proclamations of the death of scientific realism, the past few years have witnessed several book-length resurrections. Like the undead, realism is proving hard to finish off once and for all. In the preface to his book, Ilkka Niiniluoto suggests that the realism debate will never generate a consensus; it is an eternal problem of philosophy. Certainly, since the flourishing of work on the subject two decades ago, it has become clear that some disputes between realists and antirealists are destined to remain unresolved due to a lack of shared assumptions. Nevertheless, there remain problems for realists to tackle if they are to demonstrate that the position is coherent.

Recent philosophy of science has been seized by what may appear a schizophrenic attitude towards analytic metaphysics. Some philosophers of science have embraced metaphysical theorizing as an important tool for interpreting and extending scientific theories, while others reject analytic metaphysics as misguided, futile, or epistemically impotent. The idea of naturalized metaphysics—metaphysics appropriately ‘grounded’ in the details of empirical science—offers one possibility of a rapprochement between these seemingly conflicting attitudes. In this chapter, however, it is argued that the crucial notion of ‘grounding’, and hence the idea of naturalized metaphysics itself, have not yet been articulated in a compelling manner. The beginnings of an articulation are sketched.

The number of positions identified with structural realism in philosophical debates about scientific knowledge has grown significantly in the past decade, particularly with respect to the metaphysical or ‘ontic’ approach (OSR). In recent years, several advocates of OSR have proposed a novel understanding of it in order to side-step a serious challenge faced by its original formulation, eliminative OSR. I examine the conceptual basis of the new, noneliminative view, and conclude that it too faces a serious challenge, resulting in a dilemma for ontic structuralists regarding the ontological status of objects and properties, and the relative “ontological priority” of these entities with respect to the relations in which they stand.

Subsequent to the transition from the era of natural philosophy to what we now regard as the era of the modern sciences, the latter have often been described as independent of the major philosophical preoccupations that previously informed theorizing about the natural world. The extent to which this is a naïve description is a matter of debate, and in particular, views of the place of metaphysics in the interpretation of modern scientific knowledge have varied enormously. Logical positivism spawned a distaste for metaphysics in the philosophy of science which lasts to this day, but in recent years, a renaissance in analytic metaphysics has been embraced by a growing number of philosophers of science. Those moved by distaste commonly subscribe either to a minimalist Humean metaphysic, or to a quietism about metaphysical questions generally. Those moved by attraction contend that metaphysical investigations into the natures of things like properties, causation, laws, and modality, are required in order to interpret descriptions of the world furnished by our best scientific theories. I consider the presuppositions separating these contemporary approaches to the philosophy of science, and the prospect of their resolution.

I consider the idea of a structure of fundamental physical particles being causal. Causation is traditionally thought of as involving relations between entities—objects or events—that cause and are affected. On structuralist interpretations, however, it is unclear whether or how precisely fundamental particles can be causally efficacious. On some interpretations, only relations exist; on others, particles are ontologically dependent on their relations in ways that problematize the traditional picture. I argue that thinking about causal efficacy in this context generates an inevitable pattern of reasoning. To assess the cogency of a given structuralist proposal one must take a stand with respect to a significant metaphysical challenge. Two options then emerge: skepticism about the form of structuralism at issue; or a dissolution of the challenge by means of a contentious ontological primitive. I contend that the choice between these options cannot be forced on scientific or philosophical grounds alone

Epistemological disputes in the philosophy of science often focus on the question of how restrained or expansive one should be in interpreting our best scientific theories and models. For example, some empiricist philosophers countenance only belief in their observable content, while realists of different sorts extend belief (in incompatible ways, reflecting their different versions of realism) to strictly unobservable entities, structures, events, and processes. I analyze these disputes in terms of differences regarding where to draw a line between domains in which one has warrant for belief and those in which one should suspend belief and thus remain sceptical. I consider and defend the idea that the precise location of this line is subject to a form of epistemic voluntarism, and argue that a Pyrrhonian reading of the basis of such voluntaristic choice is both natural and transformative of our understanding of these debates.

Recent philosophy has paid increasing attention to the nature of the relationship between the philosophy of science and metaphysics. In The Structure of the World: Metaphysics and Representation, Steven French offers many insights into this relationship (primarily) in the context of fundamental physics, and claims that a specific, structuralist conception of the ontology of the world exemplifies an optimal understanding of it. In this paper I contend that his messages regarding how best to think about the relationship are mixed, and in tension with one another. The tension is resolvable but at a cost: a weakening of the argument for French's structuralist ontology. I elaborate this claim in a specific case: his assertion of the superiority of a structuralist account of de re modality in terms of realism about laws and symmetries (conceived ontologically) over an account in terms of realism about dispositional properties. I suggest that these two accounts stem from different stances regarding how to theorize about scientific ontology, each of which is motivated by important aspects of physics.

In this introduction, I motivate the project of examining certain resonances between ancient skeptical positions, especially Pyrrhonism, and positions in contemporary epistemology, with special attention to recent work in the epistemology of science. One such resonance concerns the idea of suspension of judgment or belief in certain contexts or domains of inquiry, and the reasons for (or processes eventuating in) suspension. Another concerns the question of whether suspension of belief in such circumstances is voluntary, in any of the senses discussed in current work on voluntarism in epistemology, which informs recent discussions of how voluntarism regarding epistemic stances may shed light on positions like scientific realism and antirealism. The aim of this special issue is thus to explore certain analogies and disanalogies between ancient and contemporary debates about skepticism, and to consider whether and to what extent the former can provide insight into the latter.