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)

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)

Structural realism is the view that scientific theories give us knowledge only of the structure of the unobservable world. The view faces an influential objection that was first posed by Max Newman: if our knowledge of the unobservable world were strictly limited to its structure, our knowledge turns out to be trivial, for it amounts to nothing more than knowledge of the cardinality of the world. In this paper, I shall propose a response to Newman’s objection. It shall be argued (...) that in having epistemic access to the intrinsic nature of our conscious experiences—knowledge that structural realists allow for—we have knowledge of what it is to exist as concrete phenomena. With the plausible assumption that the relations of the unobservable world are also similarly concrete, one can address Newman’s objection. I shall further contrast this response to other similar responses that have been proposed, and also address the objection that this response is not available to structural realists. (shrink)

The epistemic conception of scientific progress equates progress with accumulation of scientific knowledge. I argue that the epistemic conception fails to fully capture scientific progress: theoretical progress, in particular, can transcend scientific knowledge in important ways. Sometimes theoretical progress can be a matter of new theories ‘latching better onto unobservable reality’ in a way that need not be a matter of new knowledge. Recognising this further dimension of theoretical progress is particularly significant for understanding scientific realism, since realism is naturally (...) construed as the claim that science makes theoretical progress. Some prominent realist positions are best understood in terms of commitment to theoretical progress that cannot be equated with accumulation of scientific knowledge. (shrink)

The epistemic conception of scientific progress equates progress with accumulation of scientific knowledge. I argue that the epistemic conception fails to fully capture scientific progress: theoretical progress, in particular, can transcend scientific knowledge in important ways. Sometimes theoretical progress can be a matter of new theories ‘latching better onto unobservable reality’ in a way that need not be a matter of new knowledge. Recognising this further dimension of theoretical progress is particularly significant for understanding scientific realism, since realism is naturally (...) construed as the claim that science makes theoretical progress. Some prominent realist positions are best understood in terms of commitment to theoretical progress that cannot be equated with accumulation of scientific knowledge. (shrink)

I review prominent historical arguments against scientific realism to indicate how they display a systematic overshooting in the conclusions drawn from the historical evidence. The root of the overshooting can be located in some critical, undue presuppositions regarding realism. I will highlight these presuppositions in connection with both Laudan’s ‘Old induction’ and Stanford’s New induction, and then delineate a minimal realist view that does without the problematic presuppositions.

Selective scientific realists disagree on which theoretical posits should be regarded as essential to the empirical success of a scientific theory. A satisfactory account of essentialness will show that the (approximate) truth of the selected posits adequately explains the success of the theory. Therefore, (a) the essential elements must be discernible prospectively; (b) there cannot be a priori criteria regarding which type of posit is essential; and (c) the overall success of a theory, or ‘cluster’ of propositions, not only individual (...) derivations, should be explicable. Given these desiderata, I propose a “unification criterion” for identifying essential elements. (shrink)

Much debate has ensued regarding the challenge to scientific realism provided by consideration of certain problematic episodes of theory change in the history of science. This paper contends that there is an interesting case which has been overlooked in this debate, namely the prediction of the positron by Dirac from his ‘hole’ theory, and its subsequent replacement by a theory which failed to contain a central, and essential, theoretical posit: the ‘Dirac sea’ of negative energy electrons. Accounting for this case (...) with the ‘divide and conquer’ strategy of contemporary scientific realism proves particularly troublesome, even for the structural realist. (shrink)

In this paper I challenge and adjudicate between the two positions that have come to prominence in the scientific realism debate: deployment realism and structural realism. I discuss a set of cases from the history of celestial mechanics, including some of the most important successes in the history of science. To the surprise of the deployment realist, these are novel predictive successes toward which theoretical constituents that are now seen to be patently false were genuinely deployed. Exploring the implications for (...) structural realism, I show that the need to accommodate these cases forces our notion of “structure” toward a dramatic depletion of logical content, threatening to render it explanatorily vacuous: the better structuralism fares against these historical examples, in terms of retention, the worse it fares in content and explanatory strength. I conclude by considering recent restrictions that serve to make “structure” more specific. I show however that these refinements will not suffice: the better structuralism fares in specificity and explanatory strength, the worse it fares against history. In light of these case studies, both deployment realism and structural realism are significantly threatened by the very historical challenge they were introduced to answer. (shrink)

The central motivation behind the scientific realism debate is explaining the impressive success of scientific theories. The debate has been dominated by two rival types of explanations: the first relies on some sort of static, referentially transparent relationship between the theory and the unobservable world, such as truthlikeness, representation, or structural similarity; the second relies on no robust relationship between the theory and unobservable reality at all, and instead draws on predictive similarity and the stringent methodology of science to explain (...) success. I argue that this is a false dichotomy, at least insofar as dynamical theories are concerned. The best explanation of the success of dynamical theories, I argue, must appeal to a robust but referentially opaque theory–world relation. The dynamical notion of ‘tracking’ fulfills this promise. I formulate a modified no miracles argument that is liberated from the false dichotomy and show how tracking responds to the modified argument. (shrink)

Poincaré is well known for his conventionalism and structuralism. However, the relationship between these two theses and their place in Poincaré׳s epistemology of science remain puzzling. In this paper I show the scope of Poincaré׳s conventionalism and its position in Poincaré׳s hierarchical approach to scientific theories. I argue that for Poincaré scientific knowledge is relational and made possible by synthetic a priori, empirical and conventional elements, which, however, are not chosen arbitrarily. By examining his geometric conventionalism, his hierarchical account of (...) science and defence of continuity in theory change, I argue that Poincaré defends a complex structuralist position based on synthetic a priori and conventional elements, the mind-dependence of which precludes epistemic access to mind-independent structures. (shrink)

I present an exegesis of Henri Poincaré’s metaphysical position in three key essays within his book The Value of Science. In doing so, I argue for three theses: (a) that Poincaré’s metaphysical position in these sources is incompatible with his metaphysical position in his earlier book Science and Hypothesis; (b) that the phenomenological relationism defended by Poincaré in these sources is not a form of structural realism but rather a structuralist form of empiricism and (by design) has no greater metaphysical (...) commitments than constructive empiricism; and (c) that Poincaré holds in these sources that the existence of the external world is merely a convention. These theses serve to correct misconceptions about the consistency of Poincaré’s philosophical corpus, his positions on the realism-antirealism landscape, and the scope of his conventionalism. (shrink)

According to an argument by Colin Howson, the no-miracles argument is contingent on committing the base-rate fallacy and is therefore bound to fail. We demonstrate that Howson’s argument only applies to one of two versions of the NMA. The other version, which resembles the form in which the argument was initially presented by Putnam and Boyd, remains unaffected by his line of reasoning. We provide a formal reconstruction of that version of the NMA and show that it is valid. Finally, (...) we demonstrate that the use of subjective priors is consistent with the realist implication of the NMA and show that a core worry with respect to the suggested form of the NMA can be dispelled. (shrink)

Traditionally, accounts of natural kinds have run the gamut from strongly conventionalist to strongly realist views. Recently, however, there has been a significant shift toward more conventionalist-sounding positions, even (perhaps especially) among philosophers interested in scientific classification. The impetus for this is a trend toward making anthropocentric features of categories, namely, capacities to facilitate human epistemic (and other) interests via inductive inference, central to an account of kinds. I argue that taking these features seriously is both defensible and compatible with (...) conventionalism, but not compatible with a traditional realism about kinds specifically. Moreover, hopes of achieving compatibility by revising and extending kind realism—into what I call “hyperrealism”—face an insuperable dilemma. The news for realists is not all bad, however: though kind realism proves untenable, closely associated realisms underlying the objectivity of kind discourse may be viable nonetheless. (shrink)

Ważnym elementem współczesnej dyskusji pomiędzy realizmem i antyrealizmem naukowym jest próba nadania realistycznej interpretacji historycznemu faktowi zmiany teorii w nauce. Fakt ten według L. Laudana podważa nie tylko najważniejszy argument na rzecz realizmu naukowego, ale i najważniejsze tezy tego stanowiska. Argumentem kwestionowanym przez Laudana jest twierdzenie H. Putnama, że ogromny sukces nauki w przewidywaniu zjawisk i rozwijaniu nowych technologii świadczy przynajmniej o aproksymacyjnej prawdziwości teorii naukowych. Laudan wykazuje jednak fakty z historii nauki, gdy odnoszące sukces teorie okazywały się z biegiem (...) czasu fałszywe. Powiązany z tym argument przeciwko realizmowi, zwany pesymistyczną indukcją (PI), głosi, iż skoro przeszłe teorie, które odniosły sukces, okazywały się fałszywe z perspektywy nowszych, to także obecne odnoszące sukces teorie mogą okazać się w przyszłości fałszywe. Podważa to tezę odnośnie związku sukcesu teorii z jej aproksymacyjną prawdziwością. Ważnym wyzwaniem dla realizmu naukowego staje się zatem uzgodnienie jego tez z faktem zmiany teorii w nauce. Najbardziej znaczących rozwiązań tego problemu dostarcza realizm strukturalny zaproponowany przez J. Worralla i semirealizm A. Chakrawarttiego. Oba stanowiska przyjmują tę samą strategię obrony realizmu, zwaną divide et impera, uznającą, że nie całe teorie, lecz tylko ich fragmenty bezpośrednio związane z sukcesem spełniają tezy realizmu. Realizm naukowy w tych sformułowaniach zostaje w znacznym stopniu ograniczony i osłabiony. Celem artykułu jest przedstawienie tych rozwiązań i pokazanie z jednej strony realistycznych odpowiedzi na argument PI, jakich dostarczają te stanowiska, z drugiej ograniczeń, jakie z nich wynikają dla realizmu naukowego. Osłabiona wersja realizmu, jaką one proponują, również nie jest wolna od istotnych trudności, na jakie musi odpowiedzieć zarówno realizm strukturalny, jak i semirealizm. Identyfikacja tych trudności może stanowić wskazówkę dla dalszego rozwoju stanowiska realistycznego. (shrink)

Przedmiotem artykułu jest ukazanie realizmu strukturalnego jako stanowiska realistycznego w dyskusji, prowadzonej wokół realizmu naukowego – jego wybranych zalet i słabości. Realizm strukturalny jest odpowiedzią na wyzwanie, jakie realizmowi naukowemu stawiają historyczne fakty zmiany teorii w nauce. Nawiązuje on do semantycznego ujęcia teorii naukowych i wypracowanego w tym podejściu aparatu pojęciowego. Zgodnie z realizmem strukturalnym to, co zostaje zachowane z dojrzałych teorii naukowych po zmianie teorii, to ich sformułowania matematyczne, będące abstrakcyjnymi modelami teorii. Są one aproksymacyjnie prawdziwe, gdyż reprezentują realne (...) struktury rzeczywistości w sposób wolny od ontologicznej interpretacji, narzuconej przez język teorii. Realizm strukturalny i nawiązujący do niego semirealizm, który rozszerza niezmienniczość dojrzałych teorii na własności detekcyjne obiektów fizycznych, bronią tezy realizmu naukowego w kwestii aproksymacyjnej prawdziwości teorii naukowych, interpretując realistycznie zmiany teorii naukowych. Pozostawiają jednak na boku istotny dla realizmu problem reprezentowania rzeczywistości w teoriach naukowych. Oba wspomniane stanowiska, nawiązując do modelowego ujęcia teorii naukowych, przyjmują, że reprezentacja jest izomorfizmem struktur matematycznego modelu teorii i rzeczywistości. Takie rozumienie reprezentacji jest zbyt wąskie, nie uwzględnia, że struktura zjawisk nie jest jednoznacznie określona. Strukturę tę dla teorii zastępuje matematyczny model danych, który odzwierciedla zjawiska przedstawione jako związki własności określonych przez teorię. Realistyczna interpretacja modelu danych stanowi dla realizmu strukturalnego konieczne uzupełnienie, aby spełniał on naczelną tezę realizmu, głoszącą, że nauka poznaje świat taki, jaki jest niezależnie od teorii. Stanowi to podstawę, aby broniona w realizmie strukturalnym aproksymacyjna prawdziwość teorii naukowych miała ugruntowane uzasadnienie. Wskazanie potrzeby rozszerzenia realizmu strukturalnego i semirealizmu o odpowiednią dla nich koncepcję reprezentacji jest tezą tej pracy. W artykule zostały przedstawione podstawowe elementy współczesnej dyskusji wokół realizmu naukowego oraz stanowiska realizmu strukturalnego i semirealizmu jako uzgodnienie realizmu naukowego z faktem radykalnej zmiany teorii. Następnie zostały ukazane konsekwencje, jakie dla realizmu strukturalnego wynikają z semantycznego (modelowego) ujęcia teorii naukowych i związanego z tym pojęcia reprezentacji jako izomorfizmu struktur. Ostatni fragment został poświęcony wskazaniu, że aby spełnić postulaty realizmu naukowego zarówno realizm strukturalny, jak i semirealizm powinny być uzupełnione o interpretację reprezentacji rzeczywistości w modelu danych w duchu realizmu naukowego. -------------- Zgłoszono: 17/09/2020. Zrecenzowano: 12/10/2020. Zaakceptowano do publikacji: 09/11/2020. (shrink)

The decision whether to have a realist or an anti-realist attitude towards scientific hypotheses is interpreted in this paper as a choice that scientists themselves have to face in their work as scientists, rather than as a ‘philosophical’ problem. Scientists’ choices between realism and instrumentalism are interpreted in this paper with the help of two different conceptual tools: a deflationary semantics grounded in the inferentialist approach to linguistic practices developed by some authors, and an epistemic utility function that tries to (...) represent the cognitive preferences of scientists. The first tool is applied to two different questions traditionally related to the problem of scientific realism: the non-miracle argument, and the continuity of reference. The second one is applied to the problem of unconceived alternatives, and to the distinction between realist and instrumentalist attitudes towards scientific hypotheses. (shrink)

Ontic structural realism constitutes a promising take on scientific realism, one that avoids the well‐known issues that realist stances have with underdetermination and theory change. In its most radical versions, ontic structural realism proposes a type of eliminativism about theoretical entities, ascribing ontological commitment only to the structures, and not to the objects appearing in our theories. More moderate versions of ontic structural realism have also been proposed, allowing for ‘thin’ objects in the ontology. This work connects these takes on (...) structural realism with the independent notion that there are two categorically different kinds of scientific theories, namely those that deal with interactions and those that deal with structural constraints – what are known as interaction and framework theories, respectively. By taking this classification seriously, one can arrive at a selective version of ontic structural realism which is better adapted to our scientific knowledge, in which eliminativist ontic structural realism constitutes a natural fit to framework theories, whereas the moderate version is connected to interaction theories. (shrink)

The question “what is an interpretation?” is often intertwined with the perhaps even harder question “what is a scientific theory?”. Given this proximity, we try to clarify the first question to acquire some ground for the latter. The quarrel between the syntactic and semantic conceptions of scientific theories occupied a large part of the scenario of the philosophy of science in the 20th century. For many authors, one of the two currents needed to be victorious. We endorse that such debate, (...) at least in the terms commonly expressed, can be misleading. We argue that the traditional notion of “interpretation” within the syntax/semantic debate is not the same as that of the debate concerning the interpretation of quantum mechanics. As much as the term is the same, the term “interpretation” as employed in quantum mechanics has its meaning beyond (pure) logic. Our main focus here lies on the formal aspects of the solutions to the measurement problem. There are many versions of quantum theory, many of them incompatible with each other. In order to encompass a wider variety of approaches to quantum theory, we propose a different one with an emphasis on pure formalism. This perspective has the intent of elucidating the role of each so-called “interpretation” of quantum mechanics, as well as the precise origin of the need to interpret it. (shrink)