My 1994 book, The Incommensurability Thesis, has recently been re-issued in the Routledge Revivals series.

Two options are ‘incommensurate’ when neither is better than the other, but they are not equally good. Typically, we will say that one option is better in some ways, and the other in others, but neither is better ‘all things considered’. It is tempting to think that incommensurability is vagueness—that it is indeterminate which is better—but this ‘vagueness view’ of incommensurability has not proven popular. I set out the vagueness view and its implications in more detail, and argue (...) that it can explain most of the puzzling features of incommensurability. This argument proceeds without appeal to John Broome’s ‘collapsing principle’. (shrink)

This encyclopedia entry urges what it takes to be correctives to common (mis)understandings concerning the phenomenon of incommensurability and incomparability and briefly outlines some of their philosophical upshots.

The incommensurability thesis is the thesis that the content of some alternative scientific theories is incomparable due to translation failure between the vocabulary the theories employ. This paper presents an overview of the main issues which have arisen in the debate about incommensurability. It also briefly outlines a response to the thesis based on a modified causal theory of reference which allows change of reference subsequent to initial baptism, as well as a role to description in the determination (...) of reference. On such a view. the content of theories may be compared on the basis of shared reference, despite failure of translation. Two recent developments involving the incomnensurability thesis are also examined: (i) the taxonomic version of the incomensurability thesis found in Kuhn’s later writings. (ii) Hoyningen-Huenc’s neo-Kantian interpretation of Kuhn’s metaphysics. (shrink)

Comparative philosophy between two disparate cultural-philosophic traditions, such as Western and Chinese philosophy, has become a new trend of philosophical fashion in the late twentieth and early twenty-first centuries. Having learned from the past, contemporary comparative philosophers cautiously safeguard their comparative studies against two potential pitfalls, namely cultural universalism and cultural relativism. The Orientalism that assumed the superiority of the Occidental has become a memory of the past. The historical pendulum has apparently swung to the other extreme. The more recent (...) "reverse Orientalism" has started to reclaim the superiority of the Oriental. We have even been told that the twenty-first... (shrink)

Attempting to compare scientific theories requires a philosophical model of meaning. Yet different scientific theories have at times—particularly in early chemistry—pre-supposed disparate theories of meaning. When two theories of meaning are incommensurable, we must say that the scientific theories that rely upon them are meta-incommensurable. Meta- incommensurability is a more profound sceptical threat to science since, unlike first-order incommensurability, it implies complete incomparability.

The paper explores the relativistic implications of the thesis of incommensurability. A semantic form of incommensurability due to semantic variation between theories is distinguished from a methodological form due to variation in methodological standards between theories. Two responses to the thesis of semantic incommensurability are dealt with: the first challenges the idea of untranslatability to which semantic incommensurability gives rise; the second holds that relations of referential continuity eliminate semantic incommensurability. It is then argued that (...) methodological incommensurability poses little risk to the rationality or objectivity of science. For rational theory choice need neither be dictated by an algorithm nor governed by a binding set of rules. The upshot of the discussion is deflationary. There is little prospect for a relativistic conception of science based on inflated claims about the incommensurability of scientific theories. (shrink)

Two options are incommensurate in value if neither is better than the other, and if a small improvement or worsening of one does not necessarily make it determinately better or worse than the other. If a person faces a sequence of choices between incommensurate options, she may end up with a worse options than she could have had, even though none of her choices are irrational. Yet it seems that rationality should save her from this bad outcome. This is the (...) practical problem posed by incommensurability of values, and it may be solved by a new account of practical reasoning. (shrink)

This introductory article describes the phenomena of incommensurability and incomparability, how they are related, and why they are important. Since incomparability is the more significant phenomenon, the paper takes that as its focus. It gives a detailed account of what incomparability is, investigates the relation between the incomparability of values and the incomparability of alternatives for choice, distinguishes incomparability from the related phenomena of parity, indeterminacy, and noncomparability, and, finally, defends a view about practical justification that vindicates the importance (...) of incomparability — assuming it exists — for practical reason. (shrink)

Against the received translation-failure interpretation, this book presents a presuppositional interpretation of incommensurability, that is, the thesis of incommensurability as cross-language communication breakdown due to the incompatible metaphysical presuppositions underlying two competing presuppositional languages, such as scientific languages. This semantically sound, epistemologically well-established, and metaphysically profound interpretation not only affirms the tenability of the notion of incommensurability and confirms the reality of the phenomenon of incommensurability, but also makes some significant contributions to the discussion of many (...) related issues, such as the notion of conceptual schemes, the notion of truth-value status and truth-value conditions, and the issue of cross-language understanding and communication. (shrink)

Scientists working within a paradigm must play by the rules of the game of that paradigm in solving problems, and that is why incommensurability arises when the rules of the game change. If we deny the thesis of the priority of paradigms, then there is no good argument for the incommensurability of theories and thus for taxonomic incommensurability, because there is no invariant way to determine the set of results provable, puzzles solvable, and propositions cogently formulable under (...) a given paradigm. (shrink)

I criticize Kuhn’s (1962/1970) taxonomic incommensurability thesis as follows. (i) His argument for it is neither deductively sound nor inductively correct. (ii) It clashes with his account of scientific development that employs evolutionary theory. (iii) Even if two successive paradigms are taxonomically incommensurable, they have some overlapping theoretical claims, as selectivists point out. (iv) Since scientific revolutions were rare in the recent past, as historical optimists observe, they will also be rare in the future. Where scientific revolution is rare, (...) taxonomic incommensurability is rare, and taxonomic commensurability is common. For these reasons, taxonomic commensurability rather than incommensurability should be advanced as an image of science. (shrink)

Opening remarks delivered at "Incommensurability (and related matters)" conference, Hanover, June 1999.

This book concentrates on three topics: the problem of the semantic incommensurability of theories; the non-algorithmic character of rational scientific theory choice and naturalised accounts of the rationality of methodological change. The underlying aim is to show how the phenomenon of extensive conceptual and methodological variation in science need not give rise to a thorough-going epistemic or conceptual relativism.

Recently, some of the leading proponents of the view that there is widespread incommensurability among goods have suggested that the incommensurability of some goods is a constitutive feature of the goods themselves. So, for example, a friendship and a million dollars are incommensurable because it is part of what it is to be a friendship that it be incommensurable with money. According to these ‘constitutive incommensurabilists’ incommensurability follows from the very nature of certain goods. In this paper, (...) I examine this idea and argue that constitutive incommensurabilists have mistaken for constitutive incommensurability a particular emphatic kind of comparability. This examination involves an account of ‘higher’ and ‘lower’ goods and an explanation of how goods of different ‘types’ figure in practical conflict. (shrink)

The article tries to show that what is often called 'Moderate Deontology' is incoherent.

This is a short introductory discussion of the idea of incommensurability as it is used in the philosophy of science.

Along with “paradigm” and “scientific revolution,” “incommensurability” is one of the three most influential expressions associated with the “new philosophy of science” first articulated in the early 1960s by Thomas Kuhn and Paul Feyerabend. But, despite the fact that it has been widely discussed, opinions still differ widely as to the content and significance of the claim of incommensurability.

Incommensurability may be regarded as driving specialisation, on the one hand, and as posing some problems to interdisciplinarity, on the other hand. It may be argued, however, that incommensurability plays no role in either specialisation or interdisciplinarity. Scientific specialties could be defined as simply 'different' (that is, about different things), rather than 'incommensurable' (that is, competing for the explanation of the same phenomena). Interdisciplinarity could be viewed as the co- ordinated effort of scientists possessing complemetary and interlocking skills, (...) and not as the overcoming of some sort of incommensurable divide. This article provides a comprehensive evaluative examination of the relations between specialisation, interdisciplinarity, and incommensurability. Its aim is to defend the relevance of incommensurability to both specialisation and interdisciplinarity. At the same time, it aims at correcting the tendency, common among many philosophers, to regard incommensurability in a restrictive manner - such as, for example, as an almost purely semantic issue. (shrink)

In this paper, I argue that there is neither valid deductive support nor strong inductive support for Kuhn’s incommensurability thesis. There is no valid deductive support for Kuhn’s incommensurability thesis because, from the fact that the reference of the same kind terms changes or discontinues from one theoretical framework to another, it does not necessarily follow that these two theoretical frameworks are taxonomically incommensurable. There is no strong inductive support for Kuhn’s incommensurability thesis, since there are rebutting (...) defeaters against it in the form of episodes from the history of science that do not exhibit discontinuity and replacement, as Kuhn’s incommensurability thesis predicts, but rather continuity and supplementation. If this is correct, then there are no compelling epistemic reasons to believe that Kuhn’s incommensurability thesis is true or probable. (shrink)

Kuhn's alleged taxonomic interpretation of incommensurability is grounded on an ill defined notion of untranslatability and is hence radically incomplete. To supplement it, I reconstruct Kuhn's taxonomic interpretation on the basis of a logical-semantic theory of taxonomy, a semantic theory of truth-value, and a truth-value conditional theory of cross-language communication. According to the reconstruction, two scientific languages are incommensurable when core sentences of one language, which have truth values when considered within its own context, lack truth values when considered (...) within the context of the other due to the unmatchable taxonomic structures underlying them. So constructed, Kuhn's mature interpretation of incommensurability does not depend upon the notion of truth-preserving translatability, but rather depends on the notion of truth-value-status-preserving cross-language communication. The reconstruction makes Kuhn's notion of incommensurability a well grounded, tenable and integrated notion.Author Keywords: Incommensurability; Thomas Kuhn; Taxonomic structures; Lexicons; Truth-value; Untranslatability; Cross-language communication. (shrink)

According to the received translational interpretation of incommensurability, incommensurability is viewed as untranslatability due to radical variance of meaning or reference of the terms in two competing scientific languages. The author argues that the translational approach to incommensurability does not effectively clarify the concept of incommensurability. Since it cannot provide us with tenable, integrated concept of incommensurability, it should be rejected.

Local opposition to infrastructure projects implementing renewable energy (RE) such as wind farms is often strong even if state-wide support for RE is strikingly high. The slogan “Not In My BackYard” (NIMBY) has become synonymous for this kind of protest. This paper revisits the question of what is wrong with NIMBYs about RE projects and how to best address them. I will argue that local opponents to wind farm (and other RE) developments do not necessarily fail to contribute their fair (...) share to producing a desirable public good (clean energy). In fact, with landscape concerns being at the heart of much protest, the question of fair burden distribution becomes sidelined: landscape impacts cannot be distributed nor compensated for. Protests may be attempts to express a true conflict of (incommensurable) values. Understanding them as such will help us better address NIMBY concerns and overcome such opposition through ensuring procedural justice. (shrink)

An apparent incommensurability of two leading gravitational paradigms (metric and nonmetric) is considered. It is conjectured that the application of neutral language of A.P. Lightman, D.L. Lee and Kip S. Thorne (“The Foundation of Theory of Gravitational Theories”. Phys. Rev. D 1973, vol.7, pp.3563-3572) can help to solve the theory –choice problem in principle. Key words: neutral language, theory choice, gravity.

Some theorists believe that there is a plurality of values, and that in many circumstances these values are incommensurable, or at least incomparable. Others believe that all values are reducible to a single super-value, or that even if there is a plurality of irreducible values these values are commensurable. But I will argue that both sides have got it wrong. Values are neither commensurable nor incommensurable, at least not in the way most people think. We are free to believe in (...) incommensurability or not, depending on what particular conception of morality we want to embrace. Incommensurability is accordingly not a theory about value. It is a presupposition that provides a necessary background condition for a certain kind of value to exist. It is therefore not the kind of view that can be morally true or false. As a presupposition, it can only be accepted or rejected on grounds that do not presuppose that morality already exists. Incommensurability is, like the rejection of hard determinism, one of the presuppositions on which morality as we know it happens to be based. (shrink)

Philosophers and historians of science have made the claim that successive scientific theories are incommensurable, that is, that many or all of their concepts fail to coincide. This claim has been echoed by cognitive psychologists who have applied it to the successive conceptual schemes of young children, or of children and adults. This paper examines the psychological evidence for the claim and proposes ways of reinterpreting it which do not involve imputing incommensurability. An alternative approach to understanding conceptual change (...) is suggested, according to which novel concepts are introduced against a background of shared concepts, rather than as part of incommensurable conceptual schemes. (shrink)

In his paper, "Free Choice, Incommensurable Goods and the Self-Refutation of Determinism,"' Joseph Boyle seeks to show how the argument for the self-refutation of determinism - first articulated over twenty-five years ago - is an argument whose force depends on (first) a proper understanding of just what free choice is, and (secondly) a proper understanding of how free choice is a principle of moral responsibility. According to Boyle, a person can make a genuinely free choice only if he is presented (...) with alternative options that are incommensurable in their goodness or desirability. If the goodness or desirability of alternative options could be commensurated, or compared in accordance with some common standard, then it would be possible in principle for a person to determine which of the two options offered more, and which offered less, of the same sort of good represented by the two options. But if this sort of commensuration or comparison were possible, according to Boyle, then there would really be no need to choose. Rather, the only task that would have to be performed in order to determine the person's selection among alternative options would be the task clarifying or calculating which of the alternative options offered most fully what it is that makes both options desirable in the first place. Once the clarification or calculation is done, there would be no need-and in fact, no possibility--of really choosing: the calculation alone would settle which option is the best option, and thus which option is to be selected. Now if genuinely free choice requires that the choosing person be presented with options that are incommensurable in goodness or desirability, then it also seems to be the case that genuine choice-and the moral responsibility that goes along with it-requires that the person be presented with alternative possibilities from which to choose. And yet some compatibilist thinkers have held that moral responsibility does not really require the presence of alternative possibilities. In particular, Harry G. Frankfurt has sought to show (by means of counter-example) that a person can be a moral agent and morally responsible, even if the person did not, in fact, have any alternative possibilities available to him (that is, even if the person could not have done otherwise). Frankfurt's counter-example offers a direct challenge to the sort of incompatibilism that Boyle seeks to defend; and so Boyle is quite right to address Frankfurt head-on. For if Frankfurt is right, then it is erroneous to hold "the principle of alternative possibilities" (the principle that a person can be morally responsible for what he has done, only if he had alternative possibilities, or only if he could have done otherwise). But if it is erroneous to hold the principle of alternative possibilities, then it also seems erroneous to hold the more robust position that Boyle wishes to defend: namely, the position that moral responsibility requires not only alternative possibilities, but also alternative possibilities representing options that are incommensurable in their goodness. (shrink)

If the term "relativism" is understood as relativists take it, everyone is a relativist. If, on the other hand, one understands "relativism" as absolutists do, no one really could consistently be a relativist, despite what they might think. As I hope to show, however, much of this positioning of persons and philosophies is foolish. It misses much that is important in philosophical discussion and focuses attention in directions that lead to dead ends.

review of Ruth Chang's collection in which I argue that the apparent agreements between the authors disguise underlying important differences.

According to the accepted translation-failure interpretation, the problem of incommensurability involves the nature of the meaning-referential relation between scientific languages. The incommensurability thesis is that some competing scientific languages are mutually untranslatable due to the radical variance of meaning or/and reference of the terms they employ. I argue that this interpretation faces many difficulties and cannot give us a tenable, coherent, and integrated notion of incommensurability. It has to be rejected. ;On the basis of two case studies, (...) I find that the confrontations between many classical incommensurable languages are not confrontations between two untranslatable languages with different distribution of truth values, but rather the confrontations between incompatible fundamental presuppositions at the ontological level. We can always identify a truth-value gap between two incommensurable languages. Such a truth-value gap indicates a communication breakdown between the two language communities on the one hand, and is caused by the incompatible fundamental presuppositions underlying them on the other. ;I thereby identify the truth-value functional relationship between sentences, instead of the meaning-referential relationship between terms, as the dominant semantic relation between two incommensurable languages. According to my presuppositional interpretation of incommensurability, the real secret of incommensurability lies in the ontological setup of two competing presuppositional languages. When two presuppositional languages with incompatible factual commitments encounter with each other, the confrontation leads to a truth-value gap, and consequently a communication breakdown between them. Formally put, two scientific languages are incommensurable when core sentences of one language, which have truth values when considered within its own context, lack truth values when considered within the context of the other due to an ontological gap between them. ;The presuppositional interpretation makes many significant contributions to the discussion of the issue of incommensurability and the related metaphysical and epistemological issues: It confirms the existence of the phenomenon of incommensurability and makes it metaphysically and epistemologically significant. It establishes the tenability and integrity of the notion of incommensurability. It avoids many alleged unattractive epistemological and metaphysical consequences of the translation-failure interpretation. (shrink)

This is a comment on Lena Soler's 'The Incommensurability of Experimental Practices'.

Dignity, according to some recent arguments, is a useless concept, giving vague expression to moral intuitions that are better captured by other, better defined concepts. In this paper, I defend the concept of dignity against such skeptical arguments. I begin with a description of the defining features of the Kantian conception of dignity. I then examine one of the strongest arguments against that conception, advanced by Arthur Schopenhauer in On the Basis of Morality. After considering some standard accounts of dignity, (...) showing how they fail adequately to address Schopenhauer’s concern, I propose and defend a new account of dignity, drawing on the ontology of Jean-Luc Nancy. (shrink)

The paper briefly reviews the main formulations of the incommensurability thesis by Feyerabend and Kuhn, as well as the main criticisms leveled against it. The question is then raised of whether there is a "phenomenon" of incommensurability that has been "discovered". It is argued that there is no such phenomenon.

What factors are involved in the resolution of scientific disputes? What factors make the resolution of such disputes rational? The traditional view confers an important role on observation statements that are shared by proponents of competing theories. Rival theories make incompatible (sometimes contradictory) observational predictions about a particular situation, and the prediction made by one theory is borne out while the prediction made by the other is not. Paul Feyerabend, Thomas Kuhn, and Paul Churchland have called into question this account (...) of theory-resolution. According to these philosophers, substantially different and competing scientific theories are semantically incommensurable: those theories do not share a common observation language. Two charges have been leveled against the semantic incommensurability theories. The first is that it ignores that some semantic features of observational terms (e.g., their reference) can be expressed by proponents of competing theories. The second is that the semantic incommensurability thesis is self-defeating. In this paper I will argue that both of these charges are true but not for the reasons usually given. (shrink)

I reply to James Marcum’s “What’s the Support for Kuhn’s Incommensurability Thesis? A Response to Mizrahi and Patton”.

John Broome has argued that value incommensurability is vagueness, by appeal to a controversial about comparative indeterminacy. I offer a new counterexample to the collapsing principle. That principle allows us to derive an outright contradiction from the claim that some object is a borderline case of some predicate. But if there are no borderline cases, then the principle is empty. The collapsing principle is either false or empty.

More than 50 years after the publication of Thomas Kuhn’s seminal book, The Structure of Scientific Revolutions, this volume assesses the adequacy of the Kuhnian model in explaining certain aspects of science, particularly the social and epistemic aspects of science. One argument put forward is that there are no good reasons to accept Kuhn’s incommensurability thesis, according to which scientific revolutions involve the replacement of theories with conceptually incompatible ones. Perhaps, therefore, it is time for another “decisive transformation in (...) the image of science by which we are now possessed.” Only this time, the image of science that needs to be transformed is the Kuhnian one. Does the Kuhnian image of science provide an adequate model of scientific practice? If we abandon the Kuhnian picture of revolutionary change and incommensurability, what consequences would follow from that vis-à-vis our understanding of scientific knowledge as a social endeavour? -/- The essays in this collection continue this debate, offering a critical examination of the arguments for and against the Kuhnian image of science as well as their implications for our understanding of science as a social and epistemic enterprise. (shrink)

Incommensurability was Kuhn’s worst mistake. If it is to be found anywhere in science, it would be in physics. But revolutions in theoretical physics all embody theoretical unification. Far from obliterating the idea that there is a persisting theoretical idea in physics, revolutions do just the opposite: they all actually exemplify the persisting idea of underlying unity. Furthermore, persistent acceptance of unifying theories in physics when empirically more successful disunified rivals can always be concocted means that physics makes a (...) persistent implicit assumption concerning unity. To put it in Kuhnian terms, underlying unity is a paradigm for paradigms. We need a conception of science which represents problematic assumptions concerning the physical comprehensibility and knowability of the universe in the form of a hierarchy, these assumptions becoming less and less substantial and more and more such that their truth is required for science, or the pursuit of knowledge, to be possible at all, as one goes up the hierarchy. This hierarchical conception of science has important Kuhnian features, but also differs dramatically from the view Kuhn expounds in his The Structure of Scientific Revolutions. In this paper, I compare and contrast these two views in a much more detailed way than has been done hitherto. I show how the hierarchical view can be construed to emerge from Kuhn’s view as it is modified to overcome objections. I argue that the hierarchical conception of science is to be preferred to Kuhn’s view. (shrink)

Orthodox decision theory gives no advice to agents who hold two goods to be incommensurate in value because such agents will have incomplete preferences. According to standard treatments, rationality requires complete preferences, so such agents are irrational. Experience shows, however, that incomplete preferences are ubiquitous in ordinary life. In this paper, we aim to do two things: (1) show that there is a good case for revising decision theory so as to allow it to apply non-vacuously to agents with incomplete (...) preferences, and (2) to identify one substantive criterion that any such non-standard decision theory must obey. Our criterion, Competitiveness, is a weaker version of a dominance principle. Despite its modesty, Competitiveness is incompatible with prospectism, a recently developed decision theory for agents with incomplete preferences. We spend the final part of the paper showing why Competitiveness should be retained, and prospectism rejected. (shrink)

Totalism is the view that one distribution of well-being is better than another just in case the one contains a greater sum of well-being than the other. Many philosophers, following Parfit, reject totalism on the grounds that it entails the repugnant conclusion: that, for any number of excellent lives, there is some number of lives that are barely worth living whose existence would be better. This paper develops a theory of welfare aggregation---the lexical-threshold view---that allows totalism to avoid the repugnant (...) conclusion, as well as its analogues involving suffering populations and the lengths of individual lives. The theory is grounded in some independently plausible views about the structure of well-being, identifies a new source of incommensurability in population ethics, and avoids some of the implausibly extreme consequences of other lexical views, without violating the intuitive separability of lives. (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)

This paper is the introduction to the volume. It gives an argumentative view of the philosophical landscape concerning incommensurability and incomparability. It argues that incomparability, not incommensurability, is the important phenomenon on which philosophers should be focusing and that the arguments for the existence of incomparability are so far not compelling.

I argue that a standard formulation of hinge epistemology is host to epistemic relativism and show that two leading hinge approaches (Coliva’s acceptance account and Pritchard’s nondoxastic account) are vulnerable to a form of incommensurability that leads to relativism. Building on both accounts, I introduce a new, minimally epistemic conception of hinges that avoids epistemic relativism and rationally resolves hinge disagreements. According to my proposed account, putative cases of epistemic incommensurability are rationally resolvable: hinges are propositions that are (...) the objects of our belief-like attitudes and are rationally revisable in virtue of our overarching commitment to avoid systematic deception in our epistemic practices. (shrink)

This article explores the main similarities and differences between Derek Parfit’s notion of imprecise comparability and a related notion I have proposed of parity. I argue that the main difference between imprecise comparability and parity can be understood by reference to ‘the standard view’. The standard view claims that 1) differences between cardinally ranked items can always be measured by a scale of units of the relevant value, and 2) all rankings proceed in terms of the trichotomy of ‘better than’, (...) ‘worse than’, and ‘equally good’. Imprecise comparability, which can be understood in terms of the more familiar notions of cardinality and incommensurability, rejects only the first claim while parity rejects both claims of the standard view. -/- I then argue that insofar as those attracted to imprecise comparability assume that all rankings are trichotomous, as Parfit appears to, the view should be rejected. This is because imprecise equality is not a form of equality but is a sui generis ‘fourth’ basic way in which items can be ranked. We should, I argue, understand imprecise equality as parity, and imprecise comparability as entailing ‘tetrachotomy’ – that if two items are comparable, one must better than, worse than, equal to, or on a par with the other. Thus those attracted to the idea that cardinality can be imprecise should abandon trichotomy and accept parity and tetrachotomy instead. -/- Finally, I illustrate the difference between Parfit’s trichotomous notion of imprecise comparability and parity by examining how each notion might be employed in different solutions to the problem posed by the Repugnant Conclusion in population ethics. I suggest that parity provides the arguably more ecumenical solution to the problem. (shrink)

According to Critical-Level Views in population axiology, an extra life improves a population only if that life’s welfare exceeds some fixed ‘critical level.’ An extra life at the critical level leaves the new population equally good as the original. According to Critical-Range Views, an extra life improves a population only if that life’s welfare exceeds some fixed ‘critical range.’ An extra life within the critical range leaves the new population incommensurable with the original. -/- In this paper, I sharpen some (...) old objections to these views and offer some new ones. Critical-Level Views cannot avoid certain Repugnant and Sadistic Conclusions. Critical-Range Views imply that lives featuring no good or bad components whatsoever can nevertheless swallow up and neutralise goodness or badness. Both classes of view entail that certain small changes in welfare correspond to worryingly large differences in contributive value. -/- I then offer a view that retains much of the appeal of Critical-Level and Critical-Range Views while avoiding the above pitfalls. On the Imprecise Exchange Rates View, the quantity of some good required to outweigh a given unit of some bad is imprecise. This imprecision is the source of incommensurability between lives and populations. (shrink)

We argue that a semantics for counterfactual conditionals in terms of comparative overall similarity faces a formal limitation due to Arrow’s impossibility theorem from social choice theory. According to Lewis’s account, the truth-conditions for counterfactual conditionals are given in terms of the comparative overall similarity between possible worlds, which is in turn determined by various aspects of similarity between possible worlds. We argue that a function from aspects of similarity to overall similarity should satisfy certain plausible constraints while Arrow’s impossibility (...) theorem rules out that such a function satisfies all the constraints simultaneously. We argue that a way out of this impasse is to represent aspectual similarity in terms of ranking functions instead of representing it in a purely ordinal fashion. Further, we argue against the claim that the determination of overall similarity by aspects of similarity faces a difficulty in addition to the Arrovian limitation, namely the incommensurability of different aspects of similarity. The phenomena that have been cited as evidence for such incommensurability are best explained by ordinary vagueness. (shrink)

If A is better than B and B is better than C, then A is better than C, right? Larry Temkin and Stuart Rachels say: No! Betterness is nontransitive, they claim. In this paper, I discuss the central type of argument advanced by Temkin and Rachels for this radical idea, and argue that, given this view very likely has sceptical implications for practical reason, we would do well to identify alternative responses. I propose one such response, which employs the idea (...) that rational agents might regard some options as incommensurate in value, and will reasonably employ a heuristic of status quo maintenance to avoid suboptimal choices from incommensurate goods. (shrink)

In his late years, Thomas Kuhn became interested in the process of scientific specialization, which does not seem to possess the destructive element that is characteristic of scientific revolutions. It therefore makes sense to investigate whether and how Kuhn’s insights about specialization are consistent with, and actually fit, his model of scientific progress through revolutions. In this paper, I argue that the transition toward a new specialty corresponds to a revolutionary change for the group of scientists involved in such a (...) transition. I will clarify the role of the scientific community in revolutionary changes and characterize the incommensurability across specialties as possessing both semantic and methodological aspects. The discussion of the discovery of the structure of DNA will serve both as an illustration of my main argument and as reply to one criticism raised against Kuhn—namely, that his model cannot capture cases of revolutionary yet non-disruptive episodes of scientific progress. Revisiting Kuhn’s ideas on specialization will shed new light on some often overlooked features of scientific change. (shrink)