I argue that Quinean naturalists’ holism-based arguments against analyticity and apriority are more difficult to resist than is generally supposed, for two reasons. First, although opponents of naturalism sometimes dismiss these arguments on the grounds that the holistic premises on which they depend are unacceptably radical, it turns out that the sort of holism required by these arguments is actually quite minimal. And second, although it’s true, as Grice and Strawson pointed out long ago, that these arguments can succeed only (...) if there isn’t any principled criterion for meaning change, such a criterion turns out to be hard to come by. David Chalmers has recently argued that such a criterion must exist, since the norms governing belief revision are subject to obvious exceptions that can be explained only by appeal to meaning change. But this, I argue, is incorrect: if choices about how to use language are themselves rationally assessable, then there are no such exceptions to be explained. To show that this is so, I formulate a new kind of coherence norm that may be useful for reasoning formally about the relationship between meaning and evidence. (shrink)

Kant -- drawing on his eighteenth-century predecessors -- provided a discerning and powerful characterization of what biologists had to explain in organic form. His difference from the rest is that he opined that was impossible to explain it. Its ’inscrutability’ was intrinsic. The third ’Critique’ essentially proposed the reduction of biology to a kind of prescientific descriptivism, doomed never to attain authentic scientificity. By contrast, for Locke, and ’a fortiori’ for Buffon and his followers, ’intrinsic purposiveness’ was a fact of (...) the matter about concrete biological phenomena; the features of internal self-regulation were hypotheses arising out of actual research practice. The difference comes most vividly to light once we recognize Kant’s distinction of the concept of organism from the concept of life. (edited). (shrink)

The paper proposes a synthesis between human scientists and artificial representation learning models as a way of augmenting epistemic warrants of realist theories against various anti-realist attempts. Towards this end, the paper fleshes out unconceived alternatives not as a critique of scientific realism but rather a reinforcement, as it rejects the retrospective interpretations of scientific progress, which brought about the problem of alternatives in the first place. By utilising adversarial machine learning, the synthesis explores possibility spaces of available evidence for (...) unconceived alternatives providing modal knowledge of what is possible therein. As a result, the epistemic warrant of synthesised realist theories should emerge bolstered as the underdetermination by available evidence gets reduced. While shifting the realist commitment away from theoretical artefacts towards modalities of the possibility spaces, the synthesis comes out as a kind of perspectival modelling. (shrink)

An overview of Quine's understanding of the analytic/synthetic distinction, especially as it is conveyed in his paper, "The Two Dogmas of Empiricism.".

During the past few decades, a radical shift has occurred in how philosophers conceive of the relation between science and philosophy. A great number of analytic philosophers have adopted what is commonly called a ‘naturalistic’ approach, arguing that their inquiries ought to be in some sense continuous with science. Where early analytic philosophers often relied on a sharp distinction between science and philosophy—the former an empirical discipline concerned with fact, the latter an a priori discipline concerned with meaning—philosophers today largely (...) follow Willard Van Orman Quine (1908-2000) in his seminal rejection of this distinction. -/- This book offers a comprehensive study of Quine’s naturalism. Building on Quine’s published corpus as well as thousands of unpublished letters, notes, lectures, papers, proposals, and annotations from the Quine archives, this book aims to reconstruct both the nature (chapters 2-4) and the development (chapter 5-7) of his naturalism. As such, this book aims to contribute to the rapidly developing historiography of analytic philosophy, and to provide a better, historically informed, understanding of what is philosophically at stake in the contemporary naturalistic turn. (shrink)

One worrying aspect of contemporary Western Society is the increasing prevalence of instances of ‘Science Denial’ in popular culture. Examples include both cases where well-attested scientific hypotheses are rejected and conversely, where scientifically discredited ideas are stubbornly retained. The paper raises the question whether the kind of argument for an anti-realist conception of empirical scientific theory considered in my contribution to the inaugural issue of this journal could in principle provide intellectual succour for these trends. The discussion proceeds through an (...) examination of the role of ‘takings for granted’ in all reflective enquiry to the conclusion that a trusting acceptance of the general credibility of informants is a precondition for the exercise of individual epistemic responsibility, and that in that context an acceptance of at least the empirical adequacy, if not the truth, realistically understood, of the teachings of scientists in general is rationally non-optional. (shrink)

I revisit my 1993 paper on Putnam and mathematical realism focusing on the indispensability argument and how it has fared over the years. This argument starts from the claim that mathematics is an indispensable part of science and draws the conclusion, from holistic considerations about confirmation, that the ontology of science includes abstract objects as well as the physical entities science deals with.

SummaryTake the following version of scientific realism: we have good reason to believe that (some of the) current scientific theories tell us something specific about the underlying, i.e. unobservable, structures of the world, for instance that there are electrons with a certain electric charge, or that there are viruses that cause certain diseases. Popper, the rationalist, would not have adhered to the proposed formulation of scientific realism in terms of the rationality of existential beliefs concerning unobservables. Popper did not believe (...) in belief. According to Van Fraassen, the empiricist, one may yet have a rational existential belief concerning unobservables, given a liberal notion of rationality of belief. In this paper I will investigate to what extent a reassessment of both Popper’s rejection of the rationality of belief and Van Fraassen’s reformulation of the rationality of belief, points towards a new and pragmatist dissolution of the ‘problem of scientific realism’. (shrink)

Theoretical equivalence and duality are two closely related notions: but their interconnection has so far not been well understood. In this paper I explicate the contribution of a recent schema for duality to discussions of theoretical equivalence. I argue that duality suggests a construal of theoretical equivalence in the physical sciences. The construal is in terms of the isomorphism of models, as defined by the schema. This construal gives interpretative constraints that should be useful for discussions of theoretical equivalence more (...) generally. I illustrate the construal in various formulations of Maxwell’s electromagnetic theory. (shrink)

This paper explores the options available to the anti-realist to defend a Quinean empirical under-determination thesis using examples of dualities. I first explicate a version of the empirical under-determination thesis that can be brought to bear on theories of contemporary physics. Then I identify a class of examples of dualities that lead to empirical under-determination. But I argue that the resulting under-determination is benign, and is not a threat to a cautious scientific realism. Thus dualities are not new ammunition for (...) the anti-realist. The paper also shows how the number of possible interpretative options about dualities that have been considered in the literature can be reduced, and suggests a general approach to scientific realism that one may take dualities to favour. (shrink)

Im ersten Teil unseres Aufsatzes charakterisieren wir den Beitrag der ‘modernen’ Wissenschaftstheorie zur Methodologie des Textverstehens; im zweiten Teil diskutieren wir exemplarisch zwei Konzeptionen der ‘neueren’ Hermeneutik. Ziel dieser kritischen Untersuchungen ist eine Förderung des Dialogs zwischen Wissenschaftstheorie, Hermeneutik und Literaturwissenschaft.

Debate about the epistemic prowess of historical science has focused on local underdetermination problems generated by a lack of historical data; the prevalence of information loss over geological time, and the capacities of scientists to mitigate it. Drawing on Leonelli’s recent distinction between ‘phenomena-time’ and ‘data-time’ I argue that factors like data generation, curation and management significantly complexifies and undermines this: underdetermination is a bad way of framing the challenges historical scientists face. In doing so, I identify circumstances of epistemic (...) scarcity where underdetermination problems are particularly salient, and discuss cases where legacy data—data generated using differing technologies and systems of practice—are drawn upon to overcome underdetermination. This suggests that one source of overcoming underdetermination is our knowledge of science’s past. Further, data-time makes agnostic positions about the epistemic fortunes of scientists working under epistemic scarcity more plausible. But agnosticism seems to leave philosophers without much normative grip. So, I sketch an alternative approach: focusing on the strategies scientists adopt to maximize their epistemic power in light of the resources available to them. (shrink)

The problem of theoretical equivalence is traditionally understood as the problem of specifying when superficially dissimilar accounts of the world are reformulations of a single underlying theory. One important strategy for answering this question has been to appeal to formal relations between theoretical structures. This article presents two reasons to think that such an approach will be unsuccessful and suggests an alternative account of theoretical equivalence, based on the notion of interpretive equivalence, in which the problem is merely an instance (...) of a broader problem in the philosophy of physics. I thus conclude that there is no distinctive problem of theoretical equivalence at all. Two difficulties my approach raises for realist replies to the threat of underdetermination are then discussed, with particular emphasis on a recent reply by Norton. 1 Introduction2 Methodological Confusion3 Asymmetrical Equivalence3.1 Maxwell’s field equations3.2 Classical Lagrangian dynamics4 Formal Approaches: Quine and Glymour5 Theoretical Equivalence as Interpretive Equivalence6 Theoretical Equivalence without Interpretive Judgement?7 Lessons for Underdetermination. (shrink)

We present an elementary system of axioms for the geometry of Minkowski spacetime. It strikes a balance between a simple and streamlined set of axioms and the attempt to give a direct formalization in first-order logic of the standard account of Minkowski spacetime in [Maudlin 2012] and [Malament, unpublished]. It is intended for future use in the formalization of physical theories in Minkowski spacetime. The choice of primitives is in the spirit of [Tarski 1959]: a predicate of betwenness and a (...) four place predicate to compare the square of the relativistic intervals. Minkowski spacetime is described as a four dimensional ‘vector space’ that can be decomposed everywhere into a spacelike hyperplane - which obeys the Euclidean axioms in [Tarski and Givant, 1999] - and an orthogonal timelike line. The length of other ‘vectors’ are calculated according to Pythagora’s theorem. We conclude with a Representation Theorem relating models of our system that satisfy second order continuity to the mathematical structure called ‘Minkowski spacetime’ in physics textbooks. (shrink)

In this article, I analyze Quine’s conception of science, which is a radical defence of extensionalism on the grounds that first‐order logic is the most adequate logic for science. I examine some criticisms addressed to it, which show the role of modalities and probabilities in science and argue that Quine’s treatment of probability minimizes the intensional character of scientific language and methods by considering that probability is extensionalizable. But this extensionalizing leads to untenable results in some cases and is not (...) consistent with the fact that Quine himself admits confirmation which includes probability. Quine’s extensionalism does not account for this fact and then seems unrealistic, even if science ought to be extensional in so far as it is descriptive and mathematically expressible. (shrink)

in this paper i assess Pierre Duhem’s criticism of crucial experiments, and argue that we have reasons to vindicate their existence. i then analize the experiments carried out by Fizeau and Foucault in 1850, and criticize Duhem’s interpretation of their results. i contend that the results of crucial experiences can be described in terms that are neutral with respect to the competing theories. For that reason an experimental result is relatively stable and open to different interpretations in the light of (...) new theories. i conclude by distinguishing successful crucial experiments from decisive experiments. The former are meant to provide evidence that confirms one theory and disconfirms its rivals, but not necessarily to provide sufficient reasons for accepting or rejecting one of those theories. (shrink)

En este trabajo me ocupo de la manera en que Klimovsky concibió a las teorías y a los modelos en la ciencia. Comienzo describiendo la concepción hipotético-deductiva de las teorías empíricas de Klimovsky. Luego presento los distintos significados del término "modelo" que Klimovsky distinguió y discuto la manera en que entendió la relación entre teorías y modelos. Después analizo la concepción semántica de las teorías y señalo la ambigüedad de la posición de Klimovsky respecto de ella, a la que no (...) consideró una auténtica alternativa al método hipotético-deductivo. Expongo, entonces, una concepción proposicional de las teorías que permitiría superar aquellas críticas semanticistas que afectan a la concepción enunciativa de Klimovsky. En la conclusión intento mostrar la unidad de la concepción de Klimovsky acerca de la estructura de las teorías formales y empíricas. In this work I address the way Klimovsky conceived of theories and models in science. I start by describing Klimovsky's hypothetico-deductive conception of empirical theories. I then present the different senses of "model" identified by Klimovsky, and I discuss his understanding of the relation between theories and models. Next I analyze the semantic conception of theories, and argue that Klimovsky held an ambiguous stance towards them, insofar as he did not considered them to be a genuine alternative to the hypothetico-deductive method. I further present a propositional conception of theories that enables us to overcome various criticisms from semanticists to Klimovsky's statement conception of theories. I conclude by showing that Klimovsky embraced a unified perspective on the structure of empirical and formal theories. (shrink)

Operationalism and theoretical entities. The thesis of the“theory ladenness” of observation leads to an antinomy. In order to solve this antinomy a technical operationalism is sketched, according to which theories should in principle not contain anything that cannot be reduced to technical procedures. This implies the rejection of Quine's underdeterminacy thesis and of many views about the theoretical-observational distinction, e.g. neopositivistic views, van Fraassen's view, Sneed-Stegmüller's view. Then I argue for the following theses: 1. All scientific concepts are theory laden (...) in the sense that they allow us to anticipate possible experiences, but they have to be in principle fully observable, i.e. integrally convertible into operational-technical applications. 2. The observation/theory distinction can be maintained as a historical one: what is observable depends on the instruments that are available at any stage of the development of science. 3.In principle theoretical entities are empirically real in Hacking's sense. However, some aspects of Hacking's realism are to be criticized. Theoretical entities are to be resolved into the totality of the interrelated properties accessible to us by means of theoretical points of view embodied in scientific instruments. (shrink)

It is a commonplace in the philosophy of physics that any local physical theory can be represented using arbitrary coordinates, simply by using tensor calculus. On the other hand, the physics literature often claims that spinors \emph{as such} cannot be represented in coordinates in a curved space-time. These commonplaces are inconsistent. What general covariance means for theories with fermions, such as electrons, is thus unclear. In fact both commonplaces are wrong. Though it is not widely known, Ogievetsky and Polubarinov constructed (...) spinors in coordinates in 1965, enhancing the unity of physics and helping to spawn particle physicists' concept of nonlinear group representations. Roughly and locally, these spinors resemble the orthonormal basis or "tetrad" formalism in the symmetric gauge, but they are conceptually self-sufficient and more economical. The typical tetrad formalism is de-Ockhamized, with six extra field components and six compensating gauge symmetries to cancel them out. The Ogievetsky-Polubarinov formalism, by contrast, is Ockhamized, with most of the fluff removed. As developed nonperturbatively by Bilyalov, it admits any coordinates at a point, but "time" must be listed first. Here "time" is defined in terms of an eigenvalue problem involving the metric components and the matrix $diag$, the product of which must have no negative eigenvalues in order to yield a real symmetric square root that is a function of the metric. Thus even formal general covariance requires reconsideration; the atlas of admissible coordinate charts should be sensitive to the types and \emph{values} of the fields involved. Apart from coordinate order and the usual spinorial two-valuedness, Ogievetsky-Polubarinov spinors form, with the metric, a nonlinear geometric object, for which important results on Lie and covariant differentiation are recalled. Such spinors avoid a spurious absolute object in the Anderson-Friedman analysis of substantive general covariance. They also permit the gauge-invariant localization of the infinite-component gravitational energy in General Relativity. Density-weighted spinors exploit the conformal invariance of the massless Dirac equation to show that the volume element is absent. Thus instead of an arbitrary nonsingular matrix with 16 components, 6 of which are gauged away by a new local $O$ gauge group and one of which is irrelevant due to conformal covariance, one can, and presumably should, use density-weighted Ogievetsky-Polubarinov spinors coupled to the 9-component symmetric square root of the part of the metric that fixes null cones. Thus $\frac{7}{16}$ of the orthonormal basis is eliminated as surplus structure. Greater unity between spinors and tensors and the like is achieved, such as regarding conservation laws. Regarding the conventionality of simultaneity, an unusually wide range of $\epsilon$ values is admissible, but some extreme values are inadmissible. Standard simultaneity uniquely makes the spinor transformation law linear and independent of the metric, because transformations among the standard Cartesian coordinate systems fall within the conformal group, for which the spinor transformation law is linear. The surprising mildness of the restrictions on coordinate order as applied to the Schwarzschild solution is exhibited. (shrink)

It is a commonplace in the philosophy of physics that any local physical theory can be represented using arbitrary coordinates, simply by using tensor calculus. On the other hand, the physics literature often claims that spinors \emph{as such} cannot be represented in coordinates in a curved space-time. These commonplaces are inconsistent. What general covariance means for theories with fermions, such as electrons, is thus unclear. In fact both commonplaces are wrong. Though it is not widely known, Ogievetsky and Polubarinov constructed (...) spinors in coordinates in 1965, enhancing the unity of physics and helping to spawn particle physicists' concept of nonlinear group representations. Roughly and locally, these spinors resemble the orthonormal basis or "tetrad" formalism in the symmetric gauge, but they are conceptually self-sufficient and more economical. The typical tetrad formalism is de-Ockhamized, with six extra field components and six compensating gauge symmetries to cancel them out. The Ogievetsky-Polubarinov formalism, by contrast, is Ockhamized, with most of the fluff removed. As developed nonperturbatively by Bilyalov, it admits any coordinates at a point, but "time" must be listed first. Here "time" is defined in terms of an eigenvalue problem involving the metric components and the matrix $diag$, the product of which must have no negative eigenvalues in order to yield a real symmetric square root that is a function of the metric. Thus even formal general covariance requires reconsideration; the atlas of admissible coordinate charts should be sensitive to the types and \emph{values} of the fields involved. Apart from coordinate order and the usual spinorial two-valuedness, Ogievetsky-Polubarinov spinors form, with the metric, a nonlinear geometric object, for which important results on Lie and covariant differentiation are recalled. Such spinors avoid a spurious absolute object in the Anderson-Friedman analysis of substantive general covariance. They also permit the gauge-invariant localization of the infinite-component gravitational energy in General Relativity. Density-weighted spinors exploit the conformal invariance of the massless Dirac equation to show that the volume element is absent. Thus instead of an arbitrary nonsingular matrix with 16 components, 6 of which are gauged away by a new local $O$ gauge group and one of which is irrelevant due to conformal covariance, one can, and presumably should, use density-weighted Ogievetsky-Polubarinov spinors coupled to the 9-component symmetric square root of the part of the metric that fixes null cones. Thus $\frac{7}{16}$ of the orthonormal basis is eliminated as surplus structure. Greater unity between spinors and tensors and the like is achieved, such as regarding conservation laws. Regarding the conventionality of simultaneity, an unusually wide range of $\epsilon$ values is admissible, but some extreme values are inadmissible. Standard simultaneity uniquely makes the spinor transformation law linear and independent of the metric, because transformations among the standard Cartesian coordinate systems fall within the conformal group, for which the spinor transformation law is linear. The surprising mildness of the restrictions on coordinate order as applied to the Schwarzschild solution is exhibited. (shrink)

Decision-making typically requires judgments about causal relations: we need to know the causal effects of our actions and the causal relevance of various environmental factors. We investigate how several individuals' causal judgments can be aggregated into collective causal judgments. First, we consider the aggregation of causal judgments via the aggregation of probabilistic judgments, and identify the limitations of this approach. We then explore the possibility of aggregating causal judgments independently of probabilistic ones. Formally, we introduce the problem of causal-network aggregation. (...) Finally, we revisit the aggregation of probabilistic judgments when this is constrained by prior aggregation of qualitative causal judgments. (shrink)

The ideal of value free science states that the justification of scientific findings should not be based on non-epistemic (e.g. moral or political) values. It has been criticized on the grounds that scientists have to employ moral judgements in managing inductive risks. The paper seeks to defuse this methodological critique. Allegedly value-laden decisions can be systematically avoided, it argues, by making uncertainties explicit and articulating findings carefully. Such careful uncertainty articulation, understood as a methodological strategy, is exemplified by the current (...) practice of the Intergovernmental Panel on Climate Change (IPCC). (shrink)

Keywords: W.V.Quine claimed that relativism is paradoxical and unacceptable; nevertheless, his own views concerning truth and the underdetermination of theories by data amount to an interesting and plausible form of relativism.

This paper construes various positions in the philosophy of science and the philosophy of law as responses to the problem of underdetermination in science and in law. We begin by drawing a close analogy between the successive approaches to this problem in the two fields. In particular, we stress the analogy between conventionalism as a philosophy of science and legal realism as a philosophy of law, and between Putnam's and Dworkin's critiques of these positions. We then challenge the Putnam-Dworkin strategy, (...) arguing that their attempts to combat underdetermination are unsuccessful. We are thus led to scepticism regarding the outlook underlying the celebrated maxim, “ruled by law, not by men”. (shrink)

This paper examines Quine’s web of belief metaphor and its role in his various responses to conventionalism. Distinguishing between two versions of conventionalism, one based on the under-determination of theory, the other associated with a linguistic account of necessary truth, I show how Quine plays the two versions of conventionalism against each other. Some of Quine’s reservations about conventionalism are traced back to his 1934 lectures on Carnap. Although these lectures appear to endorse Carnap’s conventionalism, in exposing Carnap’s failure to (...) provide an explanatory account of analytic truth, they in fact anticipate Quine’s later critique of conventionalism. I further argue that Quine eventually deconstructs both his own metaphor and the thesis of under-determination it serves to illustrate. This enables him to hold onto under-determination, but at the cost of depleting it of any real epistemic significance. Lastly, I explore the implications of this deconstruction for Quine’s indeterminacy of translation thesis. (shrink)

This paper examines the epistemological significance of the present situation of underdetermination in quantum mechanics. After analyzing this underdetermination at three levels---formal, ontological, and methodological---the paper considers implications for a number of variants of the thesis of scientific realism in fundamental physics and reassesses Lakatos‘ characterization of progress in physical theory in light of the present situation. Next, this paper considers the implications of underdetermination for Weinberg’s ‘‘dream of a final theory.’’ Finally, the paper concludes by suggesting how one might (...) still think of realism and progress in fundamental physics despite the possibility of persistent underdetermination in quantum mechanics. (shrink)

In this paper I examine a series of criticisms that have been levelled against Quine's naturalized epistemology, regarding its response to the problem of scepticism. Barry Stroud and Michael Williams, assuming that Quine wishes to refute scepticism, argue that Quine not only fails to undertake this refutation, but is also committed to theses (such as the inscrutability of reference and the underdetermination of theory by evidence) which imply versions of scepticism of their own. In Quine's defence, Roger Gibson argues that (...) Quine can succeed in showing sceptical doubts to be incoherent. But I contend that both parties of this dispute wrongly assume that Quine wishes to defeat the sceptic in a traditional way. Instead, Quine is happy to 'acquiesce' in scepticism about a certain kind of justification. No logical justification of our scientific beliefs is possible on his view. But Quine thinks that pragmatic justification is possible, and acknowledging that this is his view leads to the resolution of a number of interpretive quandaries. (shrink)

This paper offers an interpretation of Quine's naturalized epistemology through the lens of Jaegwon Kim's influential critique of the same. Kim argues that Quine forces a false choice between traditional deductivist foundationalism and naturalized epistemology and contends that there are viable alternative epistemological projects. However it is suggested that Quine would reject these alternatives by reference to the same fundamental principles (underdetermination, indeterminacy of translation, extensionalism) that led him to reject traditional epistemology and propose naturalism as an alternative. Given this (...) interpretation of Quine, it is essential that a successful critic of naturalism also examine Quine's aforementioned principles. The divide between naturalist and nonnaturalist epistemology turns out to be defined by the divide between more fundamental naturalist and nonnaturalist approaches to semantics. (shrink)

Theodore Sider has argued that while there are some philosophical debates about which there is no fact of the matter, debates in normative ethics are likely not among them. This essay investigates a possible counterexample: the debate about so-called dirty hands. The essay first surveys several cases where No-Fact-of-the-Matter (NFM) claims have been made. Taking its cue from these cases, it then outlines two strategies that factualists about some domain can take, as well as two non-factualist counter strategies. Next, it (...) shows how an NFM claim can be defended for the debate about dirty hands. Finally, it argues that this NFM claim is at least as, if not more, plausible for normative ethics as it is for the other instances where NFM claims have been made. (shrink)

In this paper, I introduce a new challenge to moral realism: the skeptical argument from moral underdetermination. The challenge arises as a consequence of two recent projects in normative ethics. Both Parfit and a group called consequentializers have independently claimed that the main traditions of normative theories can agree on the set of correct particular deontic verdicts. Nonetheless, as Dietrich and List :421–479, 2017) and myself :191–221, 2018; Australas J Philos 97:511–527, 2019; Ethical Theory Moral Pract 24:999–1018, 2021a) have argued, (...) the traditions still disagree about why these are the correct verdicts. This means that we can understand the situation in terms of an idea from the philosophy of science, the underdetermination of theory by the evidence. Yet underdetermination figures in one of the most important skeptical challenges to scientific realism. I show how an analogous skeptical argument can be construed for the moral realm. I propose a standard form for that argument. I then defend it against three possible objections, arguing that it is at least as plausible as, if not more plausible than, its counterpart in the philosophy of science. (shrink)

abstractThe paper explores a new interpretation of the consequentializing project. Three prominent interpretations are criticized for neglecting the explanatory dimension of moral theories. Instead...

Mathematicians, physicists, and philosophers of physics often look to the symmetries of an object for insight into the structure and constitution of the object. My aim in this paper is to explain why this practice is successful. In order to do so, I present a collection of results that are closely related to (and in a sense, generalizations of) Beth’s and Svenonius’ theorems.

Quine often argued for a simple, untyped system of logic rather than the typed systems that were championed by Russell and Carnap, among others. He claimed that nothing important would be lost by eliminating sorts, and the result would be additional simplicity and elegance. In support of this claim, Quine conjectured that every many-sorted theory is equivalent to a single-sorted theory. We make this conjecture precise, and prove that it is true, at least according to one reasonable notion of theoretical (...) equivalence. Our clarification of Quine’s conjecture, however, exposes the shortcomings of his argument against many-sorted logic. (shrink)

Logicians and philosophers of science have proposed various formal criteria for theoretical equivalence. In this paper, we examine two such proposals: definitional equivalence and categorical equivalence. In order to show precisely how these two well-known criteria are related to one another, we investigate an intermediate criterion called Morita equivalence.

There is sometimes a sense in which one theory posits ‘less structure’ than another. Philosophers of science have recently appealed to this idea both in the debate about equivalence of theories and in discussions about structural parsimony. But there are a number of different proposals currently on the table for how to compare the ‘amount of structure’ that different theories posit. The aim of this paper is to compare these proposals against one another and evaluate them on their own merits.

Glymour and Quine propose two different formal criteria for theoretical equivalence. In this paper we examine the relationships between these criteria.

The purported fact that geometric theories formulated in terms of points and geometric theories formulated in terms of lines are “equally correct” is often invoked in arguments for conceptual relativity, in particular by Putnam and Goodman. We discuss a few notions of equivalence between first-order theories, and we then demonstrate a precise sense in which this purported fact is true. We argue, however, that this fact does not undermine metaphysical realism.

In this article, I examine whether or not the Hamiltonian and Lagrangian formulations of classical mechanics are equivalent theories. I do so by applying a standard for equivalence that was recently introduced into philosophy of science by Halvorson and Weatherall. This case study yields three general philosophical payoffs. The first concerns what a theory is, while the second and third concern how we should interpret what our physical theories say about the world. 1Introduction 2When Are Two Theories Equivalent? 3Preliminaries on (...) Classical Mechanics 3.1Hamiltonian mechanics 3.2Lagrangian mechanics 4Are Hamiltonian and Lagrangian Mechanics Equivalent Theories? 4.1Tangent bundle versus cotangent bundle 4.2Tangent bundle versus symplectic manifold 4.3Lagrangian vector field versus Hamiltonian vector field 5Conclusion Appendix. (shrink)

The underdetermination thesis poses a threat to rational choice of scientific theories. We discuss two arguments for the thesis. One draws its strength from deductivism together with the existence thesis, and the other is defended on the basis of the failure of a reliable inductive method. We adopt a partially subjective/objective pragmatic Bayesian epistemology of science framework, and reject both arguments for the thesis. Thus, in science we are able to reinstate rational choice called into question by the underdetermination thesis.

According to W. V. Quine, science advocates a physicalist ontology and an empiricist epistemology. However, Quine’s ontological physicalism includes the abstract objects of mathematics, such as numbers or sets. So, Quine’s commitments to empiricism are firm but not permanent. Quine has incorporated various elements of pragmatic thought into his philosophical outlook, that is why I advocate that Quine’s philosophy decidedly gives to the pragmatic view of empiricism.