The Quine-Duhem thesis states that we always have a choice about how praise or blame are distributed in cases of scientific justification. But in many scientific examples, there is simply no room to doubt that a particular hypothesis is responsible for a refutation or established by the observations. Fault Tracing gives a theory of independent justification from different sets of evidence. Using both real and artificial examples, it shows how to play independently established hypotheses against each other to (...) determine whether an arbitrary hypothesis needs to be altered in the light of (apparently) refuting evidence. This is a theory of the functioning of background knowledge in scientific justification, which allows for justification from the evidence independently of values. The book ends by briefly discussing the significance of these results in metaphysics and philosophy. (shrink)

While discussing the work of Kuhn and Hanson, John Greenwood (1990) misidentifies the nature of the relationship between the incommensurability of theories and the theory-ladenness of observation. After pointing out this error, I move on to consider Greenwood's main argument that the Quine-Duhem thesis suffers from a form of epistemological self-defeat if it is interpreted to mean that any recalcitrant observation can always be accommodated to any theory. Greenwood finds this interpretation implausible because some adjustments to auxiliary hypotheses (...) undermine too much of the prior observational evidence for the test theory. I argue that Greenwood mistakes the logico-metaphysical Quine-Duhem thesis for an epistemological one. All the argument he takes to undercut it actually illustrates how well the thesis works on a practical level. This is illustrated with an example from contemporary immunology. (shrink)

Quine claims that holism (i.e., the Quine-Duhem thesis) prevents us from defining synonymy and analyticity (section 2). In Word and Object, he dismisses a notion of synonymy which works well even if holism is true. The notion goes back to a proposal from Grice and Strawson and runs thus: R and S are synonymous iff for all sentences T we have that the logical conjunction of R and T is stimulus-synonymous to that of S and T. Whereas (...) Grice and Strawson did not attempt to defend this definition, I try to show that it indeed gives us a satisfactory account of synonymy. Contrary to Quine, the notion is tighter than stimulus-synonymy – particularly when applied to sentences with less than critical semantic mass (section 3). Now according to Quine, analyticity could be defined in terms of synonymy, if synonymy were to make sense: A sentence is analytic iff synonymous to self-conditionals. This leads us to the following notion of analyticity: S is analytic iff, for all sentences T, the logical conjunction of S and T is stimulus-synonymous to T; an analytic sentence does not change the semantic mass of any theory to which it may be conjoined (section 4). This notion is tighter than Quine's stimulus-analyticity; unlike stimulus-analyticity, it does not apply to those sentences from the very center of our theories which can be assented to come what may, even though they are not synthetic in the intuitive sense (section 5). Conclusion: We can have well-defined notions of synonymy and analyticity even if we embrace Quine's holism, naturalism, behaviorism, and radical translation. Quine's meaning skepticism is to be repudiated on Quinean grounds. (shrink)

Quine claims that holism (i.e., the Quine-Duhem thesis) prevents us from defining synonymy and analyticity (section 2). In "Word and Object," he dismisses a notion of synonymy which works well even if holism is true. The notion goes back to a proposal from Grice and Strawson and runs thus: R and S are synonymous iff for all sentences T we have that the logical conjunction of R and T is stimulus-synonymous to that of S and T. Whereas (...) Grice and Strawson did not attempt to defend this definition, I try to show that it indeed gives us a satisfactory account of synonymy. Contrary to Quine, the notion is tighter than stimulus-synonymy -- particularly when applied to sentences with less than critical semantic mass (section 3). Now according to Quine, analyticity could be defined in terms of synonymy, if synonymy were to make sense: A sentence is analytic iff synonymous to self-conditionals. This leads us to the following notion of analyticity: S is analytic iff, for all sentences T, the logical conjunction of S and T is stimulus-synonymous to T; an analytic sentence does not change the semantic mass of any theory to which it may be conjoined (section 4). This notion is tighter than Quine's stimulus-analyticity; unlike stimulus-analyticity, it does not apply to those sentences from the very center of our theories which can be assented to come what may, even though they are not synthetic in the intuitive sense (section 5). (shrink)

My aim in this paper is to explore an affinity between early critical theory and analytical philosophy. The affinity is in a fairly unexpected area: philosophy of science. I argue that early critical theory embraces a view of science which is a natural if somewhat unfamiliar extension of the pragmatist one defended by Quine. In particular, I argue that Horkheimer has a version of the Quine-Duhem thesis (“underdetermination of theory choice by the evidence”). How do the Frankfurt (...) and analytical versions of the underdetermination thesis differ? Quine and others have taken the thesis to motivate a form of pragmatism. What this means is that it is certain interests that ultimately determine the choice of theory: chief among them, an interest in simplicity of our theories. However, the Critical Theorists offer us a distinctly historical materialist version of the underdetermination thesis, in which it is the imperatives of the prevailing mode of production, for example, capitalism, which are decisive. The result is an unfamiliar Marxist version of an otherwise familiar thesis from the analytic tradition. (shrink)

It is argued that neither the "theory-informity" of observations nor the Quine-Duhem thesis pose any in principle threat to the objectivity of theory evaluation. The employment of exploratory theories does not generate incommensurability, but on the contrary is responsible for the mensurability and commensurability of explanatory theories, since exploratory theories enable scientists to make observations which are critical in the evaluation of explanatory theories. The employment of exploratory theories and other auxiliary hypotheses does not enable a theory to (...) always accommodate recalcitrant observations to preserve evidential equivalence with a rival theory. Explanatory theories become rapidly degenerating if exploratory theories or other auxiliary hypotheses which inform the original confirmation base are modified to accommodate recalcitrant observations. (shrink)

By and large, we think is a useful reply to our original critique of his article on the Quine–Duhem problem. But, we remain unsatisfied with several aspects of his reply. Ultimately, we do not think he properly addresses our most important worries. In this brief rejoinder, we explain our remaining worries, and we issue a revised challenge for Strevens's approach to QD.

The Duhem-Quine Thesis is the claim that it is impossible to test a scientific hypothesis in isolation because any empirical test requires assuming the truth of one or more auxiliary hypotheses. This is taken by many philosophers, and is assumed here, to support the further thesis that theory choice is underdetermined by empirical evidence. This inquiry is focused strictly on the axiological commitments engendered in solutions to underdetermination, specifically those of Pierre Duhem and W. V. Quine. (...) Duhem resolves underdetermination by appealing to a cluster of virtues called 'good sense', and it has recently been argued by Stump (Stud Hist Philos Biol Biomed Sei, 18(1):149-159,2007) that good sense is a form of virtue epistemology. This paper considers whether Quine, who's philosophy is heavily influenced by the very thesis that led Duhem to the virtues, is also led to a virtue epistemology in the face of underdetermination. Various sources of Quinian epistemic normativity are considered, and it is argued that, in conjunction with other normative commitments, Quine's sectarian solution to underdetermination amounts to a skills based virtue epistemology. The paper also sketches formal features of the novel form of virtue epistemology common to Duhem and Quine that challenges the adequacy of epistemic value truth-monism and blocks any imperialist naturalization of virtue epistemology, as the epistemic virtues are essential to the success of the sciences themselves. (shrink)

Duhem's and Quine's holistic theses, when properly understood, allow methodologically responsible ways of resolving a conflict between a theoretical system and experience; they only deny the possibility of doing it in an epistemically persuasive way. By developing a "string" model of scientific tests I argue that the pattern of interaction between the elements of a theoretical system arising in response to multiple adverse data can be helpful in locating a "weak spot" in it. Combining this model with anti-holistic (...) arguments of Popper, Greenwood, and Lakatos significantly reinforces their joint power. (shrink)

The "Duhem-Quine thesis" says that isolated hypotheses are not singularly verifiable by experience, only the whole body of a theory being able to be subjected to the test of experience. I first examine the rather divergent meanings this thesis takes when it is replaced in the different contexts of Duhem's and Quine'sphilosophies. Secondly, questions are asked about the acceptability of the thesis, its logical strength and its historical soundness. Finally, the consequences of some doubts raised by (...) this inquiry are examined especially with respect to Quine's philosophy. (shrink)

The "Duhem-Quine thesis" says that isolated hypotheses are not singularly verifiable by experience, only the whole body of a theory being able to be subjected to the test of experience. I first examine the rather divergent meanings this thesis takes when it is replaced in the different contexts of Duhem's and Quine'sphilosophies. Secondly, questions are asked about the acceptability of the thesis, its logical strength and its historical soundness. Finally, the consequences of some doubts raised by (...) this inquiry are examined especially with respect to Quine's philosophy. (shrink)

The "Duhem-Quine thesis" says that isolated hypotheses are not singularly verifiable by experience, only the whole body of a theory being able to be subjected to the test of experience. I first examine the rather divergent meanings this thesis takes when it is replaced in the different contexts of Duhem's and Quine'sphilosophies. Secondly, questions are asked about the acceptability of the thesis, its logical strength and its historical soundness. Finally, the consequences of some doubts raised by (...) this inquiry are examined especially with respect to Quine's philosophy. (shrink)

Abstract The Duhem?Quine thesis is generally presented as the radical underdetermi? nation of a theory by experimental evidence. But there is a much?neglected second aspect, i.e. the coherence or interrelatedness of the conceptual components of a theory. Although both Duhem and Quine recognised this aspect, they failed to see its consequences: it militates against the idea of radical underdetermination. Because scientific theories are coherent conceptual systems, empirical evidence penetrates, as it were, the periphery and allows the (...) localisation of central, not just peripheral hypotheses. There is then no reason to deny the existence of crucial experiments. Both these ideas are denied in the Quine?Duhem thesis. A discussion of the famous Stem?Gerlach experiment and the role of fundamental physical constants shows, however, that localisation is not only possible but essential for the validity of scientific theories. Quine's famous ?latitude of choice? turns out to be severely restricted. (shrink)

Contemporary sociology of scientific knowledge (SSK) is defined by its relativist trend. Its programme often calls for the support of philosophers, such as Duhem, Quine, and Wittgenstein. A critical re-reading of key texts shows that the main principles of relativism are only derivable with difficulty. The thesis of the underdetermination of theory doesn't forbid that Duhem, in many places, validates a correspondence-consistency theory of truth. He never said that social beliefs and interests fill the lack of underdetermination. (...) Quine's idea of a selective revision of hypotheses, as well as the neat incompatibility between holism and conventionalism, openly challenges the principles of relativism. Wittgenstein's work, which is not presented in book-form but rather as a tree, forces us to avoid aphoristic choices that credit any text-excising. This remark allows us to tackle the passages that sociological relativism is based on.Mathematical conventions are not anthropological objects. When Wittgenstein examines the "language-games," he only speaks of the functioning of natural language, not to be confused with scientific formal languages. We then should render the formula "language-game" by "well-defined, explicit and compulsory rules of communication", which is a much less attractive formula for relativism. Consequently, there does not exist a real continuity between the epistemologies of Duhem, Quine and Wittgenstein, and the recent works of the SSK. (shrink)

In Chapter 4 of [2] Grünbaum sets out to refute Einstein's philosophy of physical geometry. The latter's theory is seen as lying within the tradition of "anti-empiricist conventionalism" of Duhem and Quine as opposed to the "qualified empiricism" of Poincaré, Carnap and Reichenbach. Consequently Grünbaum sets the stage for his critique of Einstein by discussing certain of the views of these other thinkers. But in these preliminary discussions the various theses are confused and misrepresented in such a way (...) as to make it almost impossible to evaluate Grünbaum's final treatment of Einstein's thesis. For this reason I will deal only with those parts of this chapter in which the roots of Grünbaum's confusion are to be found. This will involve analyses of two theories which are not clearly distinguished by Grünbaum. The first is Duhem's denial of the "crucial experiment" in physics; the second is Quine's version of "pragmatism.". (shrink)

As in the case of great books in all branches of philosophy, Pierre Duhem's Le Théorie Physique , first published in 1906, can be looked to as the progenitor of many different and even conflicting currents in subsequent philosophy of science. On a superficial reading, it seems to be an expression of what later came to be called deductivist and instrumentalist analyses of scientific theory. Duhem's very definition of physical theory, put forward early in the book, is the (...) quintessence of instrumentalism: A physical theory is not an explanation. It is a system of mathematical propositions, deduced from a small number of principles, which aim to represent as simply, as completely, and as exactly as possible a set of experimental laws [p. 19]. (shrink)

The rejection of the idea that the so‐called Duhem‐Quine thesis in fact expresses a thesis upheld by either Duhem or Quine invites a more detailed comparison of their views. It is suggested that the arguments of each have a certain impact on the positions maintained by the other. In particular, Quine's development of his notion of ontological commitment is enlisted in the interpretation of Duhem's position. It is argued that this counts against the instrumentalist (...) construal usually put on what Duhem says about approximation and historical continuity. (shrink)

The high point of the falsification of physical theories in a standard view of the philosophy of science is the so-called crucial experiment. This experiment is a kind of manipulated empirical test, which provides the criterion for distinguishing between two rival hypotheses, where one is an acceptable theory due to passing the test, and the other turns out to be an unacceptable theory as it does not pass the test. The crucial experiment was supposed to play a significant role because, (...) in virtue of an empirical disconfirmation of one theory, the experiment was assumed to confirm the other as true. However, in 1906, in La théorie physique, son object et la structure (hereafter quoted in English translation as The Aim and Structure of Physical Theory (1906/1954)), Pierre Duhem famously argued against this view and stated that crucial experiments in physics are impossible as they are necessarily ambiguous and logically incomplete. His contention rested on the claim that, “[a] physical theory is not an explanation [of true reality in itself in virtue of some broad metaphysical ramification of physics]. It is a system of mathematical propositions, deduced from a small number of principles, which aim to represent as simply, as completely, and as accurately as possible a set of experimental laws” (ibid., p. 19). Furthermore, different theories could be equally suitable to represent a given group of experimental laws. And, assuming holism, no hypothesis could be tested in isolation, but merely as a part of a set of an entire scientific theory. The problem which Duhem identified in 1906 was slightly overshadowed and neglected in mainstream philosophy of science until the appearance of a challenging paper by Willard Van Orman Quine published in 1951 and entitled “Two Dogmas of Empiricism”. Quine’s paper caused a revival of interest in Duhem’s original formulation and gave a new impulse towards the problem in the form of the so-called Duhem-Quine thesis. The aim of this paper is to reconsider whether Duhem was right to argue that there are no crucial experiments in physics. In order to assess the validity of the thesis, first, this paper makes an exposition of Duhem’s arguments in their favour, and analyses the major criticisms of this position offered in the subject-literature of Adolf Grünbaum, who explicitly attacked the arguments for the thesis as inconclusive and false. Then, this paper presents possible modes of defence of the Duhem-Quine thesis and argues that the original formulation of the thesis is well qualified and plausible. Finally, this paper offers a pragmatic interpretation of the theory choice. (shrink)

As in the case of great books in all branches of philosophy, Pierre Duhem's Le Théorie Physique, first published in 1906, can be looked to as the progenitor of many different and even conflicting currents in subsequent philosophy of science. On a superficial reading, it seems to be an expression of what later came to be called deductivist and instrumentalist analyses of scientific theory. Duhem's very definition of physical theory, put forward early in the book, is the quintessence (...) of instrumentalism:A physical theory is not an explanation. It is a system of mathematical propositions, deduced from a small number of principles, which aim to represent as simply, as completely, and as exactly as possible a set of experimental laws [p. 19]. (shrink)

This paper considers the relevance of the Duhem-Quine thesis in economics. In the introductory discussion which follows, the meaning of the thesis and a brief history of its development are detailed. The purpose of the paper is to discuss the effects of the thesis in four specific and diverse theories in economics, and to illustrate the dependence of testing the theories on a set of auxiliary hypotheses. A general taxonomy of auxiliary hypotheses is provided to demonstrate the confounding (...) of auxiliary hypotheses with the testing of economic theory. (shrink)

Le holisme de la réfutation, outhèse de Duhem-Quine, affirme que nous ne pouvons pas tester isolément une hypothèse scientifique, mais seulement des ensembles d’hypothèses. Ainsi, en cas d’échec d’un test, nous pouvons seulement conclure qu’au moins une hypothèse d’un ensemble est falsifiée, mais nous ne pouvons pasdéterminer laquelle.Bien que cette thèse soit partagée par Duhem et Quine, on néglige régulièrementdes différences entre leurs analyses, alors qu’ilsne s’appuient pas sur les mêmes arguments, et parviennent à des conclusions (...) qui se contredisent sur des points essentiels. Nous proposonsdans cet articled’exposer leholisme duhemien, et de le comparer au holisme quinien.Nouscherchons surtout à montrer que le holisme duhemien n’empêche pasla falsifiabilité des hypothèses scientifiques. (shrink)

According to a view assumed by many scientists and philosophers of science and standardly found in science textbooks, it is controlled ex perience which provides the basis for distinguishing between acceptable and unacceptable theories in science: acceptable theories are those which can pass empirical tests. It has often been thought that a certain sort of test is particularly significant: 'crucial experiments' provide supporting empiri cal evidence for one theory while providing conclusive evidence against another. However, in 1906 Pierre Duhem (...) argued that the falsification of a theory is necessarily ambiguous and therefore that there are no crucial experiments; one can never be sure that it is a given theory rather than auxiliary or background hypotheses which experiment has falsified. w. V. Quine has concurred in this judgment, arguing that "our statements about the external world face the tribunal of sense experience not indi vidually but only as a corporate body". Some philosophers have thought that the Duhem-Quine thesis gra tuitously raises perplexities. Others see it as doubly significant; these philosophers think that it provides a base for criticism of the foundational view of knowledge which has dominated much of western thought since Descartes, and they think that it opens the door to a new and fruitful way to conceive of scientific progress in particular and of the nature and growth of knowledge in general. (shrink)

Although there are numerous similarities between Duhem and Quine, there are strong arguments which suggest that what can be isolated as Quine?s thesis would be unacceptable to Duhem. On the other hand, they both share Duhem?s holistic thesis: empirical statements are interconnected in such a way that they cannot be confirmed or refuted taken in isolation. Since Quine?s holism is more radical, as we shall show, his thesis claims that we can always keep a (...) statement by making necessary adjustments somewhere else in the system. We will try to show that only the first thesis can be rightfully ascribed to Duhem, that these two thesis are not identical, and that they are both different from what is usually called the theses of underdetermination. As we shall see, neither of them speaks about the possibility of empirically equivalent theories. They are, first and foremost, holistic theses which, under certain additional assumptions, have the thesis of underdetermination as their consequence. (shrink)

The principle of clinical equipoise requires that, aside from certain exceptional cases, second generation treatments ought to be tested against standard therapy. In violation of this principle, placebo-controlled trials (PCTs) continue to be used extensively in the development and licensure of second-generation treatments. This practice is typically justified by appeal to methodological arguments that purport to demonstrate that active-controlled trials (ACTs) are methodologically flawed. Foremost among these arguments is the so called assay sensitivity argument. In this paper, I take a (...) closer look at this argument. Following Duhem, I argue that all trials, placebo-controlled or not, rely on external information for their meaningful interpretation. Pending non-circular empirical evidence that we can trust the findings of PCTs to a greater degree than the findings of ACTs, I conclude that the assay sensitivity argument fails to demonstrate that placebo-controlled trials are preferable, methodologically or otherwise, to active-controlled trials. Contrary to the intentions of its authors, the fundamental lesson taught by the assay sensitivity argument is Duhemian: the validity of all clinical trials depends on external information. (shrink)

Résumé Le problème de Duhem-Quine a été considéré comme un problème majeur de la philosophie des sciences et a donné lieu au déploiement de nombreux efforts pour tenter de le circonvenir ou d’affaiblir ses implications. Plus récemment, le problème est devenu une question majeure au sein de la méthodologie de l’économie expérimentale. Dans cet article, l’auteur soutient que la plupart de ces discussions soit sacrifient trop du pouvoir explicatif de la science, soit ne réussissent pas à traiter proprement (...) du problème. Dans le prolongement de discussions récentes en philosophie des sciences, on peut voir que le meilleur moyen de traiter du problème est de critiquer la conception même de la science développée par Quine. JEL Classification : B41. (shrink)

Underdetermination is a relation between evidence and theory. More accurately, it is a relation between the propositions that express the (relevant) evidence and the propositions that constitute the theory. Evidence is said to underdetermine theory. This may mean two things. First, the evidence cannot prove the truth of the theory. Second, the evidence cannot render the theory probable. Let’s call the first deductive underdetermination, and the second inductive (or ampliative) underdetermination. Both kinds of claim are supposed to have a certain (...) epistemic implication, viz., that belief in theory is never warranted by the evidence. This is the underdetermination thesis. (shrink)

In what follows I will discuss an example of the Duhem-Quine problem in which Pr(H A), Pr(A H), and Pr(OI +H& ?A) (where H is the hypothesis, A the auxiliary assumptions, and O the observational prediction) can be construed objectively; however, only some of those quantities are relevant to the analysis that I provide. The example involves medical diagnosis. The goal is to test the hypothesis that someone has tuberculosis; the auxiliary assumptions describe the er- ror characteristics of (...) the test procedure. Although it can make sense to talk about the objective probability that someone (randomly drawn from a given population) has tuberculosis and it also can make sense to talk about the objective probability that a test procedure has a certain set of error characteristics, neither of these quantities will enter into the analysis. The analysis proceeds entirely via likelihoods, what one needs to consider is just the probability of the observations conditional on four conjunctions of the form (?H & +A).' It is a special feature of the example that all four of these conjunctions are simple statistical hypotheses in the technical sense that each unambigu-ously confers a probability on the observations.'o After describing how the likelihood concept applies to the example concerning medical diagnosis, I will show how similar patterns can arise in the context of a second inferential framework-that of H. Akaike's criterion of model selection;" this time the example will involve phylogenetic inference. (shrink)

Contemporary developments in economicmethodology have produced a vibrant agenda ofcompeting positions. These include, amongothers, constructivism, critical realism andrhetoric, with each contributing to the Realistvs. Pragmatism debate in the philosophies of thesocial sciences. A major development in theneo-pragmatist contribution to economicmethodology has been Quine's pragmatic assaulton the dogmas of empiricism, which are nowclearly acknowledged within contemporaryeconomic methodology. This assault isencapsulated in the celebrated Duhem-Quinethesis, which according to a number ofcontemporary leading philosophers of economics,poses a particularly serious methodologicalproblem for economics. (...) This problem, asreflected in Hausman's analysis, consists ofthe inability of economics to learn fromexperience, thereby subverting the capacity totest economic theories. In this paper wedispute this position. Our argument is basedon a combination of Quine's holism with VanFraassen's constructive empiricism, especiallythe latter's analysis of empirical adequacy andhis pragmatic approach to explanation. Theresulting reorientation of economic methodologyrestores the capacity of economics to learnfrom experience and reinstates the imperativeof developing alternatives to orthodoxtheorizing in economics. (shrink)

Quine is routinely perceived as having changed his mind about the scope of the Duhem-Quine thesis, shifting from what has been called an 'extreme holism' to a more moderate view. Where the Quine of 'Two Dogmas of Empiricism' argues that “the unit of empirical significance is the whole of science” (1951, 42), the later Quine seems to back away from this “needlessly strong statement of holism” (1991, 393). In this paper, I show that the received (...) view is incorrect. I distinguish three ways in which Quine's early holism can be said to be wide-scoped and show that he has never changed his mind about any one of these aspects of his early view. Instead, I argue that Quine's apparent change of mind can be explained away as a mere shift of emphasis. (shrink)

This paper argues that Duhem’s thesis does not decisively refute a corroboration-based account of scientific methodology (or ‘falsificationism’), but instead that auxiliary hypotheses are themselves subject to measurements of corroboration which can be used to inform practice. It argues that a corroboration-based account is equal to the popular Bayesian alternative, which has received much more recent attention, in this respect.

Duhem is often described as an anti-realist or instrumentalist. A contrary view has recently been expressed by Martin (1991) (Pierre Duhem: Philosophy and History in the Work of a Believing Physicist (La Salle, IL: Open Court)), who suggests that this interpretation makes it difficult to understand the vantage point from which Duhem argues in La science allemande (1915) that deduction, however impeccable, cannot establish truths unless it begins with truths. In the same spirit, the present paper seeks (...) to establish that Duhem is at any rate not the kind of anti-realist he is often presented as being, and that his views are like those Quine sees fit to call realist. An interpretation of Duhem's views on explanation and precision in science, and their bearing on the epistemological status of theory, is advanced which leads naturally into his critique of conventionalism. His attitude towards atomism, which should not be judged from a post-1925 perspective, is considered part of the unified view he strove after and appropriately called Duhem's physicalism, standing in contrast to the kind of reductionist conception usually associated with atomism. (shrink)

This essay traces some of Pierre Duhem's motives for his celebrated "Quine- Duhem thesis" to a specific worry about theory underdetermination that arises within classical mechanics, concerned with the rivalry between Duhem's own thermomechanical approach and the more narrowly "mechanical" treatment pursued by Hertz and others. In the context of the treatments of "physical infinitesimals" common at the time, these two approaches seem empirically indistinguishable. After an exposition of the basic issues, this alleged "underdetermination" is then (...) evaluated from a more modern perspective. (shrink)