This paper investigates the historical origins of the notion of incommensurability in contemporary philosophy of science. The aim is not to establish claims of priority, but to enhance our understanding of the notion by illuminating the various issues that contributed to its development. Kuhn developed his notion of incommensurability primarily under the influence of Fleck, Polanyi, and Köhler. Feyerabend, who had developed his notion more than a decade earlier, drew directly from Duhem, who had developed a notion of incommensurability in (...) 1906. The idea is that in the course of scientific advance, when fundamental theories change, meanings change, which can result in a new conception of the nature of reality. Feyerabend repeatedly used this notion of incommensurability to attack various forms of conceptual conservativism. These include the logical positivists’ foundational use of protocol statements, Heisenberg’s methodological principle that established results must be presupposed by all further research, attempts to separate philosophical accounts of ontology from physics, Bohr’s principle of complementarity, and logical empiricist accounts of reduction and explanation. Focusing on the function of the notion of incommensurability common to Feyerabend’s various critiques explicates Feyerabend’s early philosophy as a series of challenges to forms of conceptual conservativism.Keywords: Incommensurability; Paul Feyerabend; Thomas Kuhn; Pierre Duhem; Wolfgang Köhler; Ludwik Fleck. (shrink)

The theory of concepts advanced in the dissertation aims at accounting for a) how a concept makes successful practice possible, and b) how a scientific concept can be subject to rational change in the course of history. Traditional accounts in the philosophy of science have usually studied concepts in terms only of their reference; their concern is to establish a stability of reference in order to address the incommensurability problem. My discussion, in contrast, suggests that each scientific concept consists of (...) three components of content: 1) reference, 2) inferential role, and 3) the epistemic goal pursued with the concept's use. I argue that in the course of history a concept can change in any of these three components, and that change in one component—including change of reference—can be accounted for as being rational relative to other components, in particular a concept's epistemic goal.This semantic framework is applied to two cases from the history of biology: the homology concept as used in 19th and 20th century biology, and the gene concept as used in different parts of the 20th century. The homology case study argues that the advent of Darwinian evolutionary theory, despite introducing a new definition of homology, did not bring about a new homology concept (distinct from the pre-Darwinian concept) in the 19th century. Nowadays, however, distinct homology concepts are used in systematics/evolutionary biology, in evolutionary developmental biology, and in molecular biology. The emergence of these different homology concepts is explained as occurring in a rational fashion. The gene case study argues that conceptual progress occurred with the transition from the classical to the molecular gene concept, despite a change in reference. In the last two decades, change occurred internal to the molecular gene concept, so that nowadays this concept's usage and reference varies from context to context. I argue that this situation emerged rationally and that the current variation in usage and reference is conducive to biological practice.The dissertation uses ideas and methodological tools from the philosophy of mind and language, the philosophy of science, the history of science, and the psychology of concepts. (shrink)

Wesley Salmon and John Earman have presented influential Bayesian reconstructions of Thomas Kuhn’s account of theory-change. In this paper I argue that all attempts to give a Bayesian reading of Kuhn’s philosophy of science are fundamentally misguided due to the fact that Bayesian confirmation theory is in fact inconsistent with Kuhn’s account. The reasons for this inconsistency are traced to the role the concept of incommensurability plays with reference to the ‘observational vocabulary’ within Kuhn’s picture of scientific theories. The upshot (...) of the discussion is that it is impossible to integrate both Kuhn’s claims and Bayesianism within a coherent account of theory-change. (shrink)

Wesley Salmon and John Earman have presented influential Bayesian reconstructions of Thomas Kuhn's account of theory-change. In this paper I argue that all attempts to give a Bayesian reading of Kuhn's philosophy of science are fundamentally misguided due to the fact that Bayesian confirmation theory is in fact inconsistent with Kuhn's account. The reasons for this inconsistency are traced to the role the concept of incommensurability plays with reference to the 'observational vocabulary' within Kuhn's picture of scientific theories. The upshot (...) of the discussion is that it is impossible to integrate both Kuhn's Claims and Bayesianism within a coherent account of theory-change. (shrink)

Many discussions between realists and non-realists have centered on the issue of reference, especially whether there is referential stability during theory change. In this paper, I shall summarize the debate, sketching the problems that remain within the two opposing positions, and show that both have ended on their own slippery slope, sliding away from their original position toward that of their opponents. In the search for a viable intermediate position, I shall then suggest an account of reference which, to a (...) degree, follows the causal theory in explaining reference as carving the world at its joints. Contrary to the causal theory, however, I submit that this world is a phenomenal world whose variable joints exist only in a historical process in which they are transmitted gradually from one generation to the next. According to this account, the joints of the phenomenal world are constituted by family resemblance, where bundles of features that span bounded areas in perceptual space underlie the joints. Furthermore, the integrity of the cognitive process by which these joints are recognized depends on a transmission process by which new generations are presented with given joints and bundles by the preceding generation. Contrary to a traditional realist account, this heritage from the preceding generation may be transformed into new joints and bundles before transmission to new generations. This permits a continuous process of referential change in which the joints and bundles at different stages in the development of a theory can be connected by chains-of-reasoning. (shrink)

This paper reviews the situation with respect to the referential approach to the problem of semantic incommensurability. It argues that the thesis of semantic incommensurability does not pose a significant threat to scientific realism. However, there exists a "non-realist" defence of incommensurability, according to which the referential approach begs the question against advocates of the incommensurability thesis. This defence is criticized, and the basis for a realist response to incommensurability is presented.

The causal theory of reference is often taken to provide a solution to the problems, such as incomparability and referential discontinuity, that the meaning-change thesis raised. I show that Kuhn successfully questioned the causal theory and Putnam's idea that reference is determined via the sameness relation of essences that holds between a sample and other members of a kind in all possible worlds. Putnam's single ‘essential' properties may be necessary but not sufficient to determine membership in a kind category. Kuhn (...) argued that extension is fixed by similarity-dissimilarity relations that are liable to change in taxonomic reorganizations of science. *Received October 2009; revised January 2010. †To contact the author, please write to: Institute of Philosophy, University of Leiden, Martin de Vrieshof 4, 2300 RS Leiden, The Netherlands; e-mail: [email protected]. (shrink)

The paper gives an overview of key themes of twentieth century philosophical treatment of the language of science, with special emphasis on the meaning variance of scientific terms and the comparison of alternative theories. These themes are dealt with via discussion of the topics of: (a) the logical positivist principle of verifiability and the problem of the meaning of theoretical terms, (b) the postpositivist thesis of semantic incommensurability, and (c) the scientific realist response to incommensurability based on the causal theory (...) of reference. (shrink)

It has sometimes been suggested that the so-called new theory of reference (NTR) would provide an alternative picture of meaning and reference which avoids the unwelcome consequences of the meaning-variance thesis and incommesurability. However, numerous philosophers of science have been quite critical towards the idea and NTR in general. It is argued that many of them have an over-simplified and, in part, mistaken understanding of what NTR amounts to. It is submitted that NTR, when correctly understood, can be an important (...) ingredient in the realist toolkit for defending the rationality of science. (shrink)

In this paper I draw a connection between Kuhn and the empiricist legacy, specifically between his thesis of incommensurability, in particular in its later taxonomic form, and van Fraassen's constructive empiricism. I show that if it is the case the empirically equivalent but genuinely distinct theories do exist, then we can expect such theories to be taxonomically incommensurable. I link this to Hacking's claim that Kuhn was a nominalist. I also argue that Kuhn and van Fraassen do not differ as (...) much as might be thought as regards the claim that observation is theory laden. (shrink)

The purpose of the paper is twofold. I first outline a philosophical theory of concepts based on conceptual role semantics. This approach is explicitly intended as a framework for the study and explanation of conceptual change in science. Then I point to the close similarities between this philosophical framework and the theory theory of concepts, suggesting that a convergence between psychological and philosophical approaches to concepts is possible. An underlying theme is to stress that using a non-atomist account of concepts (...) is crucial for the successful study of conceptual development and change. (shrink)

Moti Mizrahi has argued that Thomas Kuhn does not have a good argument for the incommensurability of successive scientific paradigms. With Rouse, Andersen, and others, I defend a view on which Kuhn primarily was trying to explain scientific practice in Structure. Kuhn, like Hilary Putnam, incorporated sociological and psychological methods into his history of science. On Kuhn’s account, the education and initiation of scientists into a research tradition is a key element in scientific training and in his explanation of incommensurability (...) between research paradigms. The first part of this paper will explain and defend my reading of Kuhn. The second part will probe the extent to which Kuhn’s account can be supported, and the extent to which it rests on shaky premises. That investigation will center on Moti Mizrahi’s project, which aims to transform the Kuhnian account of science and of its history. While I do defend a modified kind of incommensurability, I agree that the strongest version of Kuhn’s account is steadfastly local and focused on the practice of science. (shrink)

The incommensurability of two theories seems to problematize theory comparisons, which allow for the selection of the better of the two theories. If so, it becomes puzzling how the quality of theories can improve with time, i.e. how science can progress across changes in incommensurable theories. I argue that in papers published in the 1990s, Kuhn provided a novel way to resolve this apparent tension between incommensurability and scientific progress. He put forward an account of their compatibility which worked not (...) by downplaying the negative consequences of incommensurability but instead by allowing them to reach their natural end: a process of specialisation. This development in Kuhn’s thought has yet to be properly recorded but it is also interesting in its own right. It shows how a robust version of incommensurability—one which really does have severe negative consequences for scientists’ capacity to perform comparative evaluations of incommensurable theories—need make no puzzle of the progress of science. (shrink)

This study intends to show that the question whether faith can be justified without proofs can be resolved by importing ideas from Kierkegaard’s and Plantinga’s affirmative take on the matter. There is a deep similarity between the way they understand belief in God and belief in Christianity: for both the first is considered universal human knowledge and the second seen as a gift from God. Against the charge that such an understanding is irrational Plantinga offers an externalist epistemological model which (...) allows those beliefs to be warranted. The authors also share the modern idea that there is an objective truth, combining it with the postmodern stance that no method exists which would guarantee access to it. A specific contribution on Kierkegaard’s part to the understanding of the rationality of transitions toward a Christian stage of existence is to show in detail the way in which such transitions are mediated through inwardnes - a perspective akin to Michael Polanyi’s scientific epistemology. One can see in both authors not only a deep commonality of ideas, but also a remarkable way in which their understandings augment each other. Whereas Plantinga’s inquiry contributes to the rational plausibility of a “Justified Faith without Reasons” project, Kierkegaard’s venture balances such a logical-analytic effort with a deep existential inquiry. (shrink)

Incommensurability has been for about forty years one of the most discussed topics on the contemporary philosophy of science. In order to tackle this issue I assume Howard Sankey’s characterization of incommensurability as “the thesis that the content of some alternative scientific theories is incomparable due to translation failure between the vocabulary the theories employ”. This kind of incomparability should pre- vent for instance the derivation of Newtonian mechanics from relativity theory, as Thomas Kuhn maintains. Since I have myself been (...) concerned with the comparison of Newtonian and Einsteinian mass concepts in Rivadulla, I focus in this short paper on the comparability of theories of contemporary theoretical physics.Thus, instead of dealing with the question of whether the theories of contemporary physics are definitely incommensurable with each other, the main aim of this paper is to provide an answer to the question of whether it makes any sense to think about the in- commensurability between contemporary physical theories, due to their obvious comparability. (shrink)

RESUMEN Las teorías de la referencia puramente descriptivistas o causales fracasan a la hora de dar cuenta del modo en que se fija y puede rastrearse la referencia de los términos teóricos. Psillos propuso dos versiones del descriptivismo causal que recogen argumentos presentes en defensas previas de dicha posición. Se trata de una teoría mixta que pretende solucionar el problema y acomodarse a intuiciones presentes en enfoques alternativos, como el que apela a oraciones de Ramsey. El artículo se propone mostrar (...) la insuficiencia del descriptivismo causal como solución al problema de la referencia de los términos teóricos. ABSTRACT Purely descriptivist or purely causal reference theories fail to account for the manner in which the reference of theoretical terms is fixed and can be traced. S. Psillos proposed two versions of causal descriptivism that take up arguments set forth in previous defenses of said position. His is a mixed theory that attempts to solve the problem by adopting insights from alternative approaches, such as those that resort to Ramsey sentences. The objective of the article is to show the insufficiency of causal descriptivism as a solution to the problem of reference of theoretical terms. (shrink)

We examine the question of whether scientific theories can ever be complete. For two closely related reasons, we will argue that they cannot. The first reason is the inability to determine what are “valid empirical observations”, a result that is based on a self-reference Gödel/Tarski-like proof. The second reason is the existence of “meta-empirical” evidence of the inherent incompleteness of observations. These reasons, along with theoretical incompleteness, are intimately connected to the notion of belief and to theses within the philosophy (...) of science: the Quine-Duhem (and underdetermination) thesis and the observational/theoretical distinction failure. Some puzzling aspects of the philosophical theses will become clearer in light of these connections. Other results that follow are: no absolute measure of the informational content of empirical data, no absolute measure of the entropy of physical systems, and no complete computer simulation of the natural world are possible. The connections with the mathematical theorems of Gödel and Tarski reveal the existence of other connections between scientific and mathematical incompleteness: computational irreducibility, complexity, infinity, arbitrariness and self-reference. Finally, suggestions will be offered of where a more rigorous (or formal) “proof” of scientific incompleteness can be found. (shrink)

A fines de los 50 y a lo largo de los años 60 Feyerabend formula su doctrina de la proliferación teórica. Con ella busca inicialmente destacar la presencia positiva de la metafísica en el proceso de explicación teórica. Concretamente, pretende dar cuenta de la impotencia de toda teoría científica de explicar realísticamente el mundo si no estuviera informada por supuestos que sus interlocutores juzgan como a-científicos o pre-científicos. Ahora bien, para poder precisar el papel que juega la metafísica en el (...) proceso de explicación teórica es preciso dilucidar qué entiende Feyerabend por realismo. Entre los especialistas existe una discusión acerca de si este defiende un realismo científico o un antirrealismo. Con el propósito de poder comprender en qué sentido Feyerabend sostiene que la metafísica provee vías de acceso para explicar el mundo, procuraremos demostrar la naturaleza normativa de su realismo. At the end of the 50s and throughout the 60s, Feyerabend formulated his doctrine of theoretical proliferation. With this doctrine, he sought to emphasize the positive presence of metaphysics in the process of theoretical explanation. In particular, he claims to account for the impotence of any scientific theory for realistically explaining the world if it was not informed by some assumptions that his partners judge as non-scientific or pre-scientific. However, in order to specify the role of metaphysics in the process of theoretical explanation it is necessary to clarify what Feyerabend understands for realism. Among specialists there is a discussion about whether he defended a scientific realism or an anti-realism. In order to be able to understand in what sense Feyerabend holds that metaphysics provides access ways to explain the world, we will try to demonstrate the normative nature of his realism. (shrink)

In his mature works, Kuhn abandons the concept of a paradigm and becomes more interested in the analysis of the conceptual structure of scientific theories. These changes are interpreted as resulting from a ‘linguistic turn’ that Kuhn underwent sometimes around the 1980s. Much of the philosophical discussions about Kuhn’s post-‘linguistic turn’ philosophy revolves around his views on taxonomic concepts. Apart from taxonomy, however, the mature Kuhn introduces other concepts, such as conceptual networks and lexicons. This article distinguishes these three concepts (...) and shows that adopting each one of them has different impacts on Kuhn’s model of science. After distinguishing and assessing the concepts of taxonomy, network, and lexicon, it will be argued that the latter not only fits the Kuhnian model of science better, but it also helps capture the wide sense of Kuhn’s early concept of a paradigm. (shrink)

I examine Thomas Kuhn’s work regarding the role played by the concept of practice in the development of his theory of scientific rationality. I outline the epistemological implications of his theory of incommensurability. I then show how the original intuition of a practice-based and social conception of incommensurability is replaced by a more conventional linguistic interpretation. I then examine Kuhn’s solution to the problem of incommensurability and explain its inadequacy. I then show that, ultimately, his failure to grasp the epistemological (...) dimension of practice prevents him from providing a fully satisfactory solution to the epistemological problem raised in The Structure of Scientific Revolutions. (shrink)

A popular rejoinder to the potential threat that incommensurability might pose to scientific realism has been the referential response: despite meaning variance, there can be referential continuity, which is sufficient for rational theory choice. This response has been charged with meta-incommensurability, according to which it begs the question by assuming realist metaphysics. However, realists take it to be a rhetorical device that hinders productive discussion. By reconstructing the debate, this paper aims to demonstrate two things. First, there are unexpected commonalities (...) between realists and non-realists, meaning that the charge of meta-incommensurability is more or less exaggerated. Second, meta-incommensurability, which is to be found in the ways to make sense of referential overlap at the token level, still plays a role in the realism debate. (shrink)

El cambio ontológico tras una revolución científica, la inquietante consecuencia de la teoría de la inconmensurabilidad de Kuhn sigue cobrando interés, desde la última década del siglo anterior la interpretación no-realista de HoyningenHuene y Oberheim ha representado un desafío para el realismo científico de Sankey, quien postula la co-referencia como posibilidad para traslape de términos intraducibles por inconmensurabilidad semántica. Argumentos en discusión sobre comparabilidad, mundo y traslape referencial parecen incompatibles entre ambos enfoques (puntos 1, 2); la interpretación kantiana de HoyningenHuene (...) de mundo fenoménico y mundo en sí mismo, acerca del mundo que cambia y mundo que no cambia por las revoluciones científicas, es inaceptable para Sankey (punto 2.1); postulo una analogía entre categorías y espacio externo de Kant con léxico y mundo en sí mismo en Kuhn, respectivamente (punto 3). (shrink)

Las teorías de la referencia puramente descriptivistas o causales fracasan a la hora de dar cuenta del modo en que se fija y puede rastrearse la referencia de los términos teóricos. Psillos propuso dos versiones del descriptivismo causal que recogen argu-mentos presentes en defensas previas de dicha posición. Se trata de una teoría mixta que pretende solucionar el problema y acomodarse a intuiciones presentes en enfo-ques alternativos, como el que apela a oraciones de Ramsey. El artículo se propone mostrar la (...) insuficiencia del descriptivismo causal como solución al problema de la referencia de los términos teóricos. (shrink)

Contrary to Sankey’s central assumption, incommensurability does not imply incomparability of content, nor threaten scientific realism by challenging the rationality of theory comparison. Moreover, Sankey equivocates between reference to specific entities by statements used to test theories and reference to kinds by theories themselves. This distinction helps identify and characterize the genuine threat that incommensurability poses to realism, which is ontological discontinuity as evidenced in the historical record: Successive theories reclassify objects into mutually exclusive sets of kinds to which they (...) refer. That is why claiming that scientific progress is an increasingly better approximation to truth is difficult to justify. Similarly, Sankey’s attack on neo-Kantian antirealist positions is based on his misunderstanding of some of the central terms of those positions, making most of his attack on them ineffectual, including his diagnosis of their incoherence. We conclude by reiterating our conviction that in this debate meta-incommensurability plays an important role.Keywords: Scientific realism; Incommensurability; Meta-incommensurability; Thomas Kuhn; Paul Feyerabend; Howard Sankey. (shrink)