The paper deals with the problem of ontological status of unobservable entities of modern physics. Author considers the question whether they are real objects or social constructs? The first point is being supported by constructive realists; the second one is backed by those who stand by a very influential strategy of the so-called social constructionism. Realists assume that intermediate vector bosons (as well as Higgs boson recently discovered by the experiments at the Large Hadron Collider) do exist in (...) reality before being predicted by the theory of electroweak interaction. They are discovered, not created. In the discourse of social constructionism, the mentioned micro-objects, on the contrary, are being created in the process of a specially set up experiments. The author confirms truthfulness of the realistic approach by analyzing the well-known in modern history of physics experiment on discovering the intermediate vector bosons. (shrink)

Can phenomenologists allow for the existence of unobservable entities such as atoms, electrons, and quarks? Can we justifiably believe in the existence of entities that are in principle unobservable? This paper addresses the relationship between Husserlian transcendental phenomenology and scientific realism. More precisely, the focus is on the question of whether there are basic epistemological principles phenomenologists are committed to that have anti-realist consequences with respect to unobservable entities. This question is relevant since Husserl’s (...) basic epistemological principles, such as the “principle of all principles,” seem to suggest that epistemic justification is limited to what can be originally given in the sense that if an object cannot be given in an originary presentive intuition, then one cannot be justified in believing that this object exists. It is the main aim of this paper to show (i) that interpretative reasons exist for not reading Husserl in such a way and (ii) that systematic reasons exist as to why phenomenologists should not subscribe to this criterion. I shall put forward a different criterion of justification that satisfies the spirit of Husserlian transcendental phenomenology and allows for justifiably believing in the existence of unobservable scientific entities. (shrink)

Una estrategia recientemente utilizada por los defensores deI realismo científico ha sido derivar implicaciones ontológicas deI contexto manipulativo-experimental. EI artículo pretende comparar y valorar dos enfoques diferentes deI argumento de la manipulabilidad -I. Hacking y R. Harré-, cuya idea basíca es que, de cara a establecer la existencia de una entidad, manipularla puede ser tan importante corno observarla. Por último, a fin de evitar los aspectos más cuestionables de ambos enfoques, propongo entender la eficacia manipulativa corno obtención de informacion fiable. (...) The ‘manipulability argument’ has been reeently employed in favour of scientific realism. The underlying idea is that, in order to establish the existence of an entity, manipulating it is so important as observing it. Two different approaches to the ’manipulability argument’ are compared: Ian Hacking’s ‘experimental realism’ and Rom Harré’s ‘depth realism’. In order to avoid the most controversial aspects of both approaches, I suggest that manipulative efficacy be understood as the attainment of reliable information. (shrink)

Una estrategia recientemente utilizada por los defensores deI realismo científico ha sido derivar implicaciones ontológicas deI contexto manipulativo-experimental. EI artículo pretende comparar y valorar dos enfoques diferentes deI argumento de la manipulabilidad -I. Hacking y R. Harré-, cuya idea basíca es que, de cara a establecer la existencia de una entidad, manipularla puede ser tan importante corno observarla. Por último, a fin de evitar los aspectos más cuestionables de ambos enfoques, propongo entender la eficacia manipulativa corno obtención de informacion fiable. (...) The ‘manipulability argument’ has been reeently employed in favour of scientific realism. The underlying idea is that, in order to establish the existence of an entity, manipulating it is so important as observing it. Two different approaches to the ’manipulability argument’ are compared: Ian Hacking’s ‘experimental realism’ and Rom Harré’s ‘depth realism’. In order to avoid the most controversial aspects of both approaches, I suggest that manipulative efficacy be understood as the attainment of reliable information. (shrink)

A careful analysis of Salmon’s Theoretical Realism and van Fraassen’s Constructive Empiricism shows that both share a common origin: the requirement of literal construal of theories inherited by the Standard View. However, despite this common starting point, Salmon and van Fraassen strongly disagree on the existence of unobservable entities. I argue that their different ontological commitment towards the existence of unobservables traces back to their different views on the interpretation of probability via different conceptions of induction. In fact, (...) inferences to statements claiming the existence of unobservable entities are inferences to probabilistic statements, whence the crucial importance of the interpretation of probability. (shrink)

I explore the process of changes in the observability of entities and objects in science and how such changes impact two key issues in the scientific realism debate: the claim that predictively successful elements of past science are retained in current scientific theories, and the inductive defense of a specific version of inference to the best explanation with respect to unobservables. I provide a case-study of the discovery of radium by Marie Curie in order to show that the observability (...) of some entities can change and that such changes are relevant for arguments seeking to establish the reliability of success-to-truth inferences with respect to unobservables. (shrink)

Relying on the notion of “overlapping perspectives,” this paper argues that entity realism and perspectivism are complementary. According to entity realism, it is justified to maintain a positive attitude toward the existence of unobservable entities with which multiple experimental interactions are possible. Perspectivism also explains that our beliefs about these entities are bounded by historically contingent theoretical and instrumental perspectives. The argument of the paper is developed through a discussion of Ronald Giere’s versions of realism: entity realism, (...) constructive realism, and perspectival realism. (shrink)

The debate on realism in physics is usually focused on the reality of unobservable entities admitted in physical theories. This reality has been often denied (e.g., by Bas van Fraassen). The present book shows that observability is a very complex notion that does not really have direct implications on ontological issues related to the existence of the non-observable entities. This is shown through historical, philosophical and scientific considerations presented in the different parts of the book. Emphasis is (...) also given to the role of experiments, measurement procedures and computer-analyzed data as interface between the theoretical and experimental cultures. (shrink)

The paper discusses the version of entity realism presented by Ian Hacking in his book, Representing and Intervening. Hacking holds that an ontological form of scientific realism, entity realism, may be defended on the basis of experimental practices which involve the manipulation of unobservable entities. There is much to be said in favour of the entity realist position that Hacking defends, especially the pragmatist orientation of his approach to realism. But there are problems with the position. The paper (...) explores two issues that reflect negatively on Hacking’s version of the entity realist position. The first issue relates to the role of description in fixing the reference of theoretical terms. The second issue relates to Hacking’s claim that the argument for entity realism based on experiment is a different kind of argument from the standard argument for scientific realism based on the success of science. (shrink)

Van Fraassen maintains that the information that we canglean from experience is limited to those entities and processes that are detectable bymeans of our unaided senses. His challenge to the realist, I suggest, is that the attemptto inferentially transcend those limits amounts to a reversion to rationalism. Under pressurefrom such examples as microscopic observation, he has recently widened the scope of thephenomena to include object-like experiences without empirical objects of experience.With this change in mind, I argue that van Fraassen (...) needs an account of perception whoseconsequence is that we can only see what we see with the unaided eye. I then argue thatreflection on the epistemically significant aspects of the perceptual process rendersvan Fraassen's characterization of the limits of experience implausible; technologicallyenhanced perception brings ``unobservables'' within those limits. An empiricismthat is compatible with realism results. (shrink)

According to Ian Hacking’s Entity Realism, unobservable entities that scientists carefully manipulate to study other phenomena are real. Although Hacking presents his case in an intuitive, attractive, and persuasive way, his argument remains elusive. I present five possible readings of Hacking’s argument: a no-miracle argument, an indispensability argument, a transcendental argument, a Vichian argument, and a non-argument. I elucidate Hacking’s argument according to each reading, and review their strengths, their weaknesses, and their compatibility with each other.

Scientific realism does not view theoretical terms as mere instruments of experimental predictions; it grants referential status to natural kind terms with 'epistemic access' and view scientific theories and terms as corresponding to physical phenomena and entities which exist independently of observation, and as thereby being the source of objective -approximate and not absolute- knowledge of the physical realm. As a result, scientific realism is accused of ontologising the unobservables. Against this charge, scientific realism posits the idea of the (...) dialectical relation between theoretical terms referring to the unobservables and scientific methods. The second argument made by realism is the ‘no miracle’ thesis. These arguments stand challenged by the Copenhagen interpretation of quantum mechanics. The aim of the paper is to examine the relevance of the two arguments of scientific realism in countering the idea that the existence of quantum states in the microphysical world renders realism obsolete. (shrink)

Carnap’s ‘Empiricism, Semantics, and Ontology’ (Carnap (1950a), ESO hereafter) is certainly a classic of twentieth century analytic philosophy. For decades now, most undergraduates are expected to read it at some point in their studies. Lately, it is being seen as the inspiration for a host of positions in the field of metaontology. Despite the widespread agreement on the importance of the paper, there is a lack of agreement on what Carnap attempts to do in the paper. My main aim in (...) this chapter is to defend an interpretation of ESO by displaying its relation to Carnap’s earlier works. My secondary goal will be to draw a lesson from this discussion for Carnap’s later work on unobservable entities in science. (shrink)

In this paper I develop five worries concerning Cartwright’s realism about entities and capacities. The first is that while she was right to insist on the ontic commitment that flows from causal explanation, she was wrong to tie these commitments solely to the entities that do the causal explaining. This move obscured the nature of causal explanation and its connection to laws. The second worry is that when she turned her attention to causal inference, by insisting on the (...) motto of ‘the most likely cause’, she underplayed her powerful argument for realism. For she focused her attention on an extrinsic feature of causal inference (or, indeed, of any ampliative inference), that is the demand of high probability, leaving behind the intrinsic qualities that causal explanation should have in order to provide the required understanding. The third worry is that her objections to Inference to the Best Explanation were unnecessarily tied to her objections about the falsity of fundamental laws. The fourth worry is that though her argument for positing capacities and being realist about them was supposed to take strength from its parallel with Sellars’s powerful argument for the indispensable explanatory role of positing unobservable entities, there are important disanalogies between the two arguments which cast doubt on the indispensability of capacities. The final (fifth) worry is that laws—perhaps brute regularities—might well have to come back from the front door, since they are still the most plausible candidates for explaining why objects have the capacities to do what they can do. (shrink)

The paper examines the role played by the notion of truth in the version of scientific realism known as scientific entity realism. Scientific entity realism is the thesis that the unobservable entities postulated by scientific theories are real. As such, it is an ontological thesis about the existence of certain entities. By contrast, scientific realism is often characterised as a thesis primarily involving the truth of theories. Sometimes scientific realism is expressed as the thesis that theoretical statements (...) are intended as true descriptions of reality. Another favoured theme is that theoretical statements are objectively true or false in virtue of the way the world is independently of us. To such formulations it is usually added that the sense of 'true' required by scientific realism is the correspondence sense. To mark the contrast with scientific entity realism, I shall say that a formulation of scientific realism in terms of truth is a semantic version of scientific realism. [For footnotes, see The Semantic Stance of Scientific Entity Realism Corrigenda in Philosophia 25 3-4 1997 481-482]. (shrink)

In this chapter I shall address the question as to whether there exists a universal and atemporal justification for the claims made by a community that adopts a particular style of reasoning. I shall present a case study in which a claim made in the laboratory style of reasoning has no universal and atemporal justification. As I shall explain, Hacking justifies his belief that unobservable entities exist on the ground that they can be regularly manipulated by experimenters in (...) order to find out and produce various phenomena (experimental realism); he also maintains that no belief that our theories are true is required in order to be realist about unobservable entities. I shall argue that his justification is relative to the laboratory style of reasoning. Ultimately, from this case study I shall draw the important conclusion that the styles of reasoning project implies epistemic relativism. In the first part of this chapter, I shall analyse Hacking’s experimental realism in the light of the styles of reasoning project. I shall start by making these points: Hacking’s theory anti-realism denies the possibility of ranking styles of reasoning in terms of their capacity to explain phenomena; furthermore, Hacking is not successful in showing that his entity realism is justified for a community that does not adopt the laboratory style of reasoning. It will follow that the styles of reasoning project is in conflict with the claim that we know about unobservable entities. (shrink)

In two studies, children's concepts of various types of ordinarily unobservable entities were examined. Study 1 confirmed earlier findings in showing that children aged 4–9 years are confident of the existence of scientific entities such as germs as well as religious beings such as God. At the same time, both age groups are skeptical of the existence of various mythical beings such as mermaids. In Study 2, older children aged 10–12 years were probed for their concepts of (...) religious as compared to scientific phenomena. Despite considerable confidence in each type, older children differentiated between them, both with respect to their level of confidence and their pattern of justification. (shrink)

This paper continues the defense of a version of scientific realism, Tautological Scientific Realism, that rests on the claim that, excluding some areas of fundamental physics about which doubts are entirely justified, many areas of contemporary science cannot be coherently imagined to be false other than via postulation of radically skeptical scenarios, which are not relevant to the realism debate in philosophy of science. In this paper we discuss, specifically, the threats of meaning change and reference failure associated with the (...) Kuhnian tradition, which depend on a descriptivist approach to meaning, and we argue that descriptivism is not the right account of the meaning and reference of theoretical terms. We suggest that an account along the lines of the causal-historical theory of reference provides a more faithful picture of how terms for unobservable theoretical entities and properties come to refer; we argue that this picture works particularly well for TSR. In the last section we discuss how our account raises concerns specifically for perspectival forms of scientific realism. (shrink)

This book addresses central issues in the philosophy and metaphysics of science, namely the nature of scientific theories, their partial truth, and the necessity of scientific laws within a moderate realist and empiricist perspective. Accordingly, good arguments in favour of the existence of unobservable entities postulated by our best theories, such as electrons, must be inductively grounded on perceptual experience and not their explanatory power as most defenders of scientific realism claim. Similarly, belief in the reality of dispositions (...) such as causal powers which ground the natural necessity of scientific laws must be based on experience. Hence, this book offers a synthetic presentation of an original metaphysics of science, namely a metaphysics of properties, both categorical and dispositional, while at the same time opposing strong versions of necessitarism according to which laws are true in all possible worlds. The main theses and arguments are clearly presented in a non-technical way. Thus, on top of being of interest to the specialists of the topics discussed, it is also useful as a textbook in courses for third year and more advanced university students. (shrink)

One might expect that empiricists would be hostile to religion. Religions are customarily based on belief in an occult realm, a realm of gods, spirits, demons, and mysterious forces. This realm is inaccessible to sense perception, which empiricists regard as our only source of knowledge. One can, however, distinguish between empiricism as a doctrine and empiricism as a stance. A liberal kind of doctrinal empiricism will allow for inferences to unobservable entities, which may also fall within the scope (...) of empiricism as a stance. Inferences to the existence of God would be of this kind, although they are unlikely to attain the standards expected in the sciences. Those who reject inferences to unobservable entities, on the other hand, will reject some (but not necessarily all) forms of “natural theology.” Empiricist assessments of religious claims will need to take into account two further facts: firstly, that they form “webs of belief” and, secondly, that they are often thought to be based on a distinct source of knowledge, namely the act of faith. (shrink)

Scientists often make surprising claims about things that no one can observe. In physics, chemistry, and molecular biology, scientists can at least experiment on those unobservable entities, but what about researchers in fields such as paleobiology and geology who study prehistory, where no such experimentation is possible? Do scientists discover facts about the distant past or do they, in some sense, make prehistory? In this book Derek Turner argues that this problem has surprising and important consequences for the (...) scientific realism debate. His discussion covers some of the main positions in philosophy of science - realism, social constructivism, empiricism, and the natural ontological attitude - and shows how they relate to issues in paleobiology and geology. His original and thought-provoking book will be of wide interest to philosophers and scientists alike. (shrink)

This chapter explores the relevance of empirical evidence to real causes. I argue for the claim that instrumentally mediated empirical results are causally dependent on unobservable entities. I develop this idea in the context of discussions on entity realism. As a consequence of my argument, an antirealist version of empiricism, which underlines the significance of empirical evidence but which abstains from real causation, is incoherent.

"The doctrine of materialism is one of the perennial and most controversial ideas in the arts and sciences. Throughout history it has aroused strong passions, and in the Sixteenth and Twentieth centuries was a doctrine over which people were persecuted and killed. Yet it has been equally aligned with empirical, enlightened and tolerant thinking. This book explores the fascinating and important philosophy of materialism in an engaging and thought-provoking way. Opening with an overview of the ideas of some of the (...) most important materialists, including Lucretius, Epicurus, Hobbes and Hume up to Darwin and Marx, Brown and Ladyman show how materialism's origins were twofold: it was an early form of scientific explanation but also an intellectual outlook, or belief-system, about the world in general. They then explain how materialism's beginnings as imaginative vision of the true nature of things faced a major challenge from modern physics, in the form of quantum theory and the general theory of relativity. This posed major questions for materialism: how could it be reconciled with unobservable entities and new discoveries about the nature of space and time? As the authors show, out of this challenge materialism did not die but re-emerged - as the new doctrine of physicalism. Drawing on colourful examples throughout - from modern physics, the nature of the mind, and atheism - the authors argue that whilst materialism may not have all the answers, its humanism and staunch belief in observation, evidence and experiment remains our best hope in a fragmented and hyper-specialised world"--. (shrink)

This volume brings together eleven essays by the distinguished philosopher of science, Peter Achinstein. The unifying theme is the nature of the philosophical problems surrounding the postulation of unobservable entities such as light waves, molecules, and electrons. How, if at all, is it possible to confirm scientific hypotheses about "unobservables"? Achinstein examines this question as it arose in actual scientific practice in three nineteenth-century episodes: the debate between particle and wave theorists of light, Maxwell's kinetic theory of gases, (...) and J.J. Thomson's discovery of the electron. The book contains three parts, each devoted to one of these topics, beginning with an essay presenting the historical background of the episode and an introduction to the philosophical issues. There is an illuminating evaluation of various scientific methodologies, including hypothetico-deductivism, inductivism, and the method of independent warrant which combines features of the first two. Achinstein assesses the philosophical validity of both nineteenth-century and modern answers to questions about unobservables, and presents and defends his own solutions. (shrink)

What does it mean to be a realist about science if one takes seriously the view that scientific knowledge is always perspectival, namely historically and culturally situated? In this book, Michela Massimi articulates an original answer to this question. The book begins with an exploration of how scientific communities often resort to several models and a plurality of practices in some areas of inquiry, drawing on examples from nuclear physics, climate science, and developmental psychology. Taking this plurality in science as (...) a starting point, Massimi explains the perspectival nature of scientific representation, the role of scientific models as inferential blueprints, and the variety of scientific realism that naturally accompanies such a view. Perspectival realism is realism about phenomena (rather than about theories or unobservable entities). The book defends this novel realist view, which places epistemic communities and their situated knowledge center stage. The result is a portrait of scientific knowledge as a collaborative inquiry, where the reliability of science is made possible by a plurality of historically and culturally situated scientific perspectives. Along the way, Massimi offers insights into the nature of scientific modelling, scientific knowledge qua modal knowledge, data-to-phenomena inferences, and natural kinds as sortal concepts. Perspectival realism is ultimately realism that takes the multicultural nature of science seriously and couples it with cosmopolitan duties about how one ought to think about scientific knowledge and the distribution of the benefits resulting from scientific advancements. (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)

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. (shrink)

I reconstruct the discovery of the Higgs boson by the ATLAS collaboration at CERN as the application of a series of inferences from effects to causes. I show to what extent such diagnostic causal inferences can be based on well established knowledge gained in previous experiments. To this extent, causal reasoning can be used to infer the existence of entities, rather than just causal relationships between them. The resulting account relies on the principle of causality, attributes only a heuristic (...) role to the theory’s predictions, and shows how, and to what extent, data selection can be used to exclude alternative causes, even “unconceived” ones. (shrink)

In this paper I address some of the problems that the historical development of science poses for a realist and discuss whether a realist construal of scientific activity is conducive to historiographical practice. First, I discuss, by means of historical examples, Ian Hacking's defense of entity realism. Second, I try to show, drawing on Kuhn's recent work on incommensurability, that the realism problem is relevant to historiography and that a realist position entails a particular historiographical strategy, which faces problems. Finally, (...) I suggest that for historiographical purposes an agnostic attitude with respect to scientific theories and unobservable entities is the most appropriate. (shrink)

In this paper I address some of the problems that the historical development of science poses for a realist and discuss whether a realist construal of scientific activity is conducive to historiographical practice. First, I discuss, by means of historical examples, Ian Hacking's defense of entity realism. Second, I try to show, drawing on Kuhn's recent work on incommensurability, that the realism problem is relevant to historiography and that a realist position entails a particular historiographical strategy, which faces problems. Finally, (...) I suggest that for historiographical purposes an agnostic attitude with respect to scientifictheories and unobservable entities is the most appropriate. (shrink)

Perspectivism is often understood as a conception according to which subjective conditions inevitably affect our knowledge and, therefore, we are never confronted with reality and facts but only with interpretations. Hence, subjectivism and anti-realism are usually associated with perspectivism. The thesis of this paper is that, especially in the case of the sciences, perspectivism can be better understood as an appreciation of the cognitive attitude that consists in considering reality only from a certain ‘point of view’, in a way that (...) can avoid subjectivism. Whereas the way of conceiving a notion is strictly subjective, the way of using it is open to intersubjective agreement, based on the practice of operations whose nature is neither mental nor linguistic. Therefore, intersubjectivity is possible within perspectivism. Perspectivism can also help understand the notion of ‘scientific objects’ in a referential sense: they are those ‘things’ that become ‘objects’ of a certain science by being investigated from the ‘point of view’ of that science. They are ‘clipped out’ of things by means of standardized operations which turn out to be the same as those granting intersubjectivity. Therefore this ‘strong’ sense of objectivity, which is clearly realist, coincides with the ‘weak’ one. The notion of truth appears fully legitimate in the case of the sciences, being clearly defined for the regional ontology of each one of them and, since this truth can be extended in an analogical sense to the theories elaborated in each science, it follows that are real also the unobservable entities postulated by those theories. (shrink)

This history of physics focuses on the question, "How do bodies act on one another across space?" The variety of answers illustrates the function of fundamental analogies or models in physics as well as the role of so-called unobservable entities. Forces and Fields presents an in-depth look at the science of ancient Greece, and it examines the influence of antique philosophy on seventeenth-century thought. Additional topics embrace many elements of modern physics--the empirical basis of quantum mechanics, wave-particle duality (...) and the uncertainty principle, and the action-at-a-distance theory of Wheeler and Feynman. 1961 ed. (shrink)

This essay aims to disentangle various types of anti-realism, and to disarm the considerations that are deployed to support them. I distinguish empiricist versions of anti-realism from constructivist versions, and, within each of these, semantic arguments from epistemological arguments. The centerpiece of my defense of a modest version of realism - real realism - is the thought that there are resources within our ordinary ways of talking about and knowing about everyday objects that enable us to extend our claims to (...) unobservable entities. This strategy, the Galilean strategy, is explained using the historical example of the telescope. (shrink)

The aim of this essay is to argue for a new version of ‘inference-to-the-best-explanation’ scientific realism, which I characterize as Best Theory Realism or ‘BTR’. On BTR, the realist needs only to embrace a commitment to the truth or approximate truth of the best theories in a field, those which are unique in satisfying the highest standards of empirical success in a mature field with many successful but falsified predecessors. I argue that taking our best theories to be true is (...) justified because it provides the best explanation of the predictive success of their predecessors and their own special success. Against standard and especially structural realism, I argue against the claim that the best explanations of the success of theories is provided by identifying their true components, such as structural relations between unobservable, which are preserved across theory change. In particular, I criticize Ladyman's and Carrier’s structural account of the success of phlogiston theory, and Worrall's well-known structural account of the success of Fresnel’s theory of light. I argue that these accounts tacitly assume the truth of our best theories, which in any case provides a better explanation of these theories’ success than the structural account. Structural realism is now defended as the only version of realism that is able to surmount the pessimistic meta-induction and the general problem that successful theories involve ontological claims concerning unobservable entities that are abandoned and falsified in theory-change. I argue that Best Theory Realism can overcome the pessimistic meta-induction and this general problem posed by theory-change. Our best theories possess a characteristic which sharply distinguishes them from their successful but false predecessors. Furthermore ‘inference-to-the-best-explanation’ confirmation can establish the truth of our best theories and thus trumps the pessimistic inductive reasoning which is supposed to show that even our best theories are most likely false in their claims concerning unobservable entities and processes. (shrink)

This essay aims to disentangle various types of anti-realism, and to disarm the considerations that are deployed to support them. I distinguish empiricist versions of anti-realism from constructivist versions, and, within each of these, semantic arguments from epistemological arguments. The centerpiece of my defense of a modest version of realism - real realism - is the thought that there are resources within our ordinary ways of talking about and knowing about everyday objects that enable us to extend our claims to (...) unobservable entities. This strategy, the Galilean strategy, is explained using the historical example of the telescope. (shrink)

When we think of scientific realism, there seem to be to ways to conceive of what it is about. The first is to see it as a view about scientific theories; the second is to see it as a view about the world. Some philosophers, most typically from Australia, think that the second way is the correct way. Scientific realism, they argue, is a metaphysical thesis: it asserts the reality of some types of entity, most typically, unobservable entities. (...) I agree that scientific realism has a metaphysical dimension, but I have insisted that it has other dimensions too. In my (1999), I took scientific realism to consist of three theses (or stances). (shrink)

In this paper, I argue that, contrary to the constructive empiricist’s position, observability is not an adequate criterion as a guide to ontological commitment in science. My argument has two parts. First, I argue that the constructive empiricist’s choice of observability as a criterion for ontological commitment is based on the assumption that belief in the existence of unobservable entities is unreasonable because belief in the existence of an entity can only be vindicated by its observation. Second, I (...) argue that the kind of ontological commitment that is under consideration when accepting a scientific theory is commitment to what I call theoretical kinds and that observation can vindicate commitment to kinds only in exceptional cases. (shrink)

The anti-realist argument from underconsideration focuses on the fact that, when scientists evaluate theories, they only ever consider a subset of the theories that can account for the available data. As a result, when scientists judge one theory to be superior to competitor theories, they are not warranted in drawing the conclusion that the superior theory is likely true with respect to what it says about unobservable entities and processes. I defend the argument from underconsideration from the objections (...) of Peter Lipton. I argue that the inconsistency that Lipton claims to find in the argument vanishes once we understand what the anti-realist means when she claims that scientists are reliable. I also argue that collapsing the distinction between relative and absolute evaluations, as Lipton recommends, has its costs. Finally, I briefly examine Richard Boyd's influential defence of realism. (shrink)

The book is a defence of scientific realism. Its primary aim is to argue that it is possible to establish scientific realism without Inference to the Best Explanation. The idea that plays the central role in the book is an "Eddington-inference". Arthur Eddington once considered a hypothetical ichthyologist who concluded from the fact that his net contained no fish smaller than the holes in his net that there were in the sea no fish smaller than the holes in his net. (...) Although Eddington himself defended the inference, the author of the present volume argues on probabilistic grounds that it is likely such an inference is flawed. He generalises the argument to develop a probabilistic justification for scientific realist claims about the existence of unobservable entities. (shrink)

The empirical underdetermination of theories is a philosophical problem which until the last century has not seriously troubled actual science. The reason is that confirmation does not depend only on empirical consequences, and theoretical virtues allow to choose among empirically equivalent theories. Moreover, I argue that the theories selected in this way are not just pragmatically or aesthetically better, but more probably true. At present in quantum mechanics not even theoretical virtues allow to choose among many competing theories and interpretations, (...) but this is because none of them possess those virtues to a sufficient degree. However, first, we can hope for some future advancement. Second, even if no further progress came forth, all the most credited competitors agree on a substantial core of theoretical assumptions. Therefore underdetermination does not show that we cannot be realist on unobservable entities in general, but at most that in particular fields our inquiry may encounter some de facto limits. (shrink)

Having assigned experience this exclusive role in justification, empiricists then have a range of views concerning the character of experience, the semantics of our claims about unobservable entities, the nature of empirical confirmation, and the possibility of non-empirical warrant for some further class of claims, such as those accepted on the basis of linguistic or logical rules. Given the definitive principle of their position, empiricists can allow that we have knowledge independent of experience only where what is known (...) is not some objective fact about the world, but something about our way of conceptualizing or describing things. Some empiricists say we have knowledge of verbal equivalences or trivialities; some argue that any non-empirical tenets are not even properly called knowledge, but should be seen as notions accepted on pragmatic rather than properly epistemic grounds. What no empiricist will allow is substantive a priori knowledge: according to empiricism we have no pure rational insight into real necessities or the inner structure of nature, but must rely on the deliverances of our senses for all of our information about external reality. Some versions of empiricism argue against the very notion of real necessities or metaphysical structure behind the phenomena; other versions take a more agnostic approach, arguing that if there is a metaphysical structure behind the phenomena it is either out of our epistemic reach, or known only to the extent that it can be grasped through experience, rather than through rational reflection. (shrink)

The discovery that the universe is fine-tuned for life ? a discovery to which the phrase ?the anthropic principle? is often applied ? has prompted much extra-cosmic speculation by philosophers, theologians, and theoretical physicists. Such speculation is referred to as extra-cosmic because an inference is made to the existence either of one unobservable entity that is distinct from the cosmos and any of its parts (God) or of many such entities (multiple universes). In this article a case is (...) mounted for the sceptical position that cosmic fine-tuning does not support an inference to anything extra-cosmic. To that end three definitions of ?fine-tuned for life? are proposed: the ?slight difference? definition, the (unconditional) probability definition, and John Leslie?s conditional probability definition. These three definitions are the only ones suggested by the relevant literature on fine-tuning and the anthropic principle. Since on none of them do claims of fine-tuning warrant an inference to something extracosmic, it is concluded that there is no definition of ?fine-tuned for life? serving this function. (shrink)

This paper develops a phenomenological defense of Ian Hacking's experimental realism about unobservable entities in physical science, employing historically undervalued resources from the phenomenological tradition in order to clarify the warrant for our ontological commitments in science. Building upon the work of Husserl, Merleau-Ponty and Heelan, the paper provides a phenomenological correction of the positivistic conception of perceptual evidence maintained by antirealists such as van Fraassen, the experimental relevance of which is illustrated through a phenomenological interpretation of the (...) 1974 discovery of the J/ ψ particle generally regarded as evidence for the charmed quark. The argument then turns to address known problems in Hacking's account, demonstrating that his own instrumentalist criterion of the real is inadequately rooted in the phenomenology of perception, and as a result, passes over the true ontological significance of experimental phenomena. The paper maintains that the proper criterion, only indirectly related to instrumentality, is the distinctive style of the real encountered in perception: empirical pregnancy. With this notion and Merleau-Ponty's associated reversibility thesis, I show that the phenomenological tradition provides insights into the warrant for our realist commitments that have yet to be adequately acknowledged by philosophers of science. (shrink)

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. (shrink)

In the Principles of Philosophy, Descartes explains several observable phenomena showing that they are caused by special arrangements of unobservable microparticles. Despite these microparticles being unobservable, many passages suggest that he was very confident that these explanations were correct. In other passages, however, Descartes points out that these explanations merely hold the status of “suppositions” or “conjectures” that could be wrong. My main goal in this chapter is to clarify this apparent conflict. I argue first that for Descartes (...) it was indeed possible to have knowledge of unobservable particles and structures, and that the possibility of natural explanations being wrong should be understood as these explanations not being absolutely certain, but only morally certain. I use the debate in contemporary philosophy of science between scientific realism and antirealism as a framework to understand how Cartesian explanations work. Especifically, I argue that Cartesian explanations rely on what Ernan McMullin calls retroduction, which is a mode of inference that justifies beliefs in concrete unobservable entities and processes, based on considerations such as simplicity, coherence, etc. This kind of justification is of common use among scientific realists. Thus, another goal of this chapter is to highlight the relevance of Descartes’ ideas about explanation in the contemporary debate on scientific realism. (shrink)

The aim of this paper is to articulate, discuss in detail and criticise Reichenbach’s sophisticated and complex argument for scientific realism. Reichenbach’s argument has two parts. The first part aims to show how there can be reasonable belief in unobservable entities, though the truth of claims about them is not given directly in experience. The second part aims to extent the argument of the first part to the case of realism about the external world, conceived of as a (...) world of independently existing entities distinct from sensations. It is argued that the success of the first part depends on a change of perspective, where unobservable entities are viewed as projective complexes vis-à-vis their observable symptoms, or effects. It is also argued that there is an essential difference between the two parts of the argument, which Reichenbach comes to accept. (shrink)