Recent work on Natural Kind Essentialism has taken a deflationary turn. The assumptions about the grounds of essentialist truths concerning natural kinds familiar from the Kripke-Putnam framework are now considered questionable. The source of the problem, however, has not been sufficiently explicated. The paper focuses on the Twin Earth scenario, and it will be demonstrated that the essentialist principle at its core (which I call IDENT)—that necessarily, a sample of a chemical substance, A, is of the same (...) kind as another sample, B, if and only if A and B have the same microstructure—must be re-evaluated. The Twin Earth scenario also assumes the falsity of another essentialist principle (which I call INST): necessarily, there is a 1:1 correlation between (all of ) the chemical properties of a chemical substance and the microstructure of that substance. This assumption will be questioned, and it will be argued that, in fact, the best strategy for defending IDENT is to establish INST. The prospects for Natural Kind Essentialism and microstructural essentialism regarding chemical substances will be assessed with reference to recent work in the philosophy of chemistry. Finally, a weakened form of INST will be presented. (shrink)

Both realist and anti-realist accounts of natural kinds possess prima facie virtues: realists can straightforwardly make sense of the apparent objectivity of the natural kinds, and anti-realists, their knowability. This paper formulates a properly anti-realist account designed to capture both merits. In particular, it recommends understanding natural kinds as ‘categorical bottlenecks,’ those categories that not only best serve us, with our idiosyncratic aims and cognitive capacities, but also those of a wide range of alternative (...) agents. By endorsing an ultimately subjective categorical principle, this view sidesteps epistemological difficulties facing realist views. Yet, it nevertheless identifies natural kinds that are fairly, though not completely, stance-independent or objective. (shrink)

This edited volume of 13 new essays aims to turn past discussions of natural kinds on their head. Instead of presenting a metaphysical view of kinds based largely on an unempirical vantage point, it pursues questions of kindedness which take the use of kinds and activities of kinding in practice as significant in the articulation of them as kinds. The book brings philosophical study of current and historical episodes and case studies from various scientific disciplines (...) to bear on natural kinds as traditionally conceived of within metaphysics. Focusing on these practices reveals the different knowledge-producing activities of kinding and processes involved in natural kind use, generation, and discovery. -/- Specialists in their field, the esteemed group of contributors use diverse empirically responsive approaches to explore the nature of kindhood. This groundbreaking volume presents detailed case studies that exemplify kinding in use. Newly written for this volume, each chapter engages with the activities of kinding across a variety of disciplines. Chapter topics include the nature of kinds, kindhood, kinding, and kind-making in linguistics, chemical classification, neuroscience, gene and protein classification, colour theory in applied mathematics, homology in comparative biology, sex and gender identity theory, memory research, race, extended cognition, symbolic algebra, cartography, and geographic information science. -/- The volume seeks to open up an as-yet unexplored area within the emerging field of philosophy of science in practice, and constitutes a valuable addition to the disciplines of philosophy and history of science, technology, engineering, and mathematics. -/- Contributions from a diverse group of established and junior scholars in the fields of Philosophy and History and Philosophy of Science including Hasok Chang, Jordi Cat, Sally Haslanger, Joyce C. Havstad, Catherine Kendig, Bernhard Nickel, Josipa Petrunic, Samuli Pöyhönen, Thomas A. C. Reydon, Quayshawn Spencer, Jackie Sullivan, Michael Wheeler, and Rasmus Grønfeldt Winther. (shrink)

In this paper I offer a unified causal account of natural kinds. Using as a starting point the widely held view that natural kind terms or predicates are projectible, I argue that the ontological bases of their projectibility are the causal properties and relations associated with the natural kinds themselves. Natural kinds are not just concatenations of properties but ordered hierarchies of properties, whose instances are related to one another as causes and effects (...) in recurrent causal processes. The resulting account of natural kinds as clusters of core causal properties that give rise to clusters of derivative properties enables us to distinguish genuine natural kinds from non-natural kinds. For instance, it enables us to say why some of the purely conventional categories derived from the social domain do not correspond to natural kinds, though other social categories may. (shrink)

It has been argued recently that some basic emotions should be considered natural kinds. This is different from the question whether as a class emotions form a natural kind; that is, whether emotion is a natural kind. The consensus on that issue appears to be negative. I argue that this pessimism is unwarranted and that there are in fact good reasons for entertaining the hypothesis that emotion is a natural kind. I interpret this to mean (...) that there exists a distinct natural class of organisms whose behavior and development are governed by emotion. These are emoters. Two arguments for the natural kind status of emotion are considered. Both converge on the existence of emotion as a distinct natural domain governed by its own laws and regularities. There are then some reasons for being optimistic about the prospects for consilience in emotion theory. 1 The mantra 2 Griffiths on emotions as natural kinds 3 Panksepp on emotions as natural kinds 4 Emotion as a neurobiological kind 5 Emotion as a psychological kind 6 Response to the mantra 7 Unification or fragmentation? 8 Concluding remarks. (shrink)

This chapter discusses the distinction between natural kinds and natural properties. Some theorists deny the distinction, and claim that natural kinds can be identified with properties. For example, natural kinds might be understood as the perfectly natural properties, reducible to properties or the extensions of properties. Alternatively, one might argue that natural kinds and natural properties are distinct and that natural kinds could be considered as a sui (...) generis type of entity. For example, one might hold that natural kinds require a distinct kind of universal, substantival universal, or sortal. Alternatively, one might claim that properties themselves form natural kind groupings, in virtue of causal mechanisms. This chapter argues that classification into natural kinds can reflect real differences between natural groups, without the supplementary ontological distinction between properties and kinds. -/- . (shrink)

It has recently been argued that the concept of natural kinds should be eliminated because it does not play a productive theoretical role and even harms philosophical research on scientific classification. We argue that this justification for eliminativism fails because the notion of ‘natural kinds’ plays another epistemic role in philosophical research, namely, it enables fruitful investigation into non-arbitrary classification. It does this in two ways: first, by providing a fruitful investigative entry into scientific classification; and (...) second—as is supported by bibliometric evidence—by tying together a research community devoted to non-arbitrary classification. The question of eliminativism then requires weighing off the benefits of retaining the concept against its harms. We argue that the progressive state of philosophical work on natural kinds tips this balance in favour of retaining the concept. (shrink)

The rosy dawn of my title refers to that optimistic time when the logical concept of a natural kind originated in Victorian England. The scholastic twilight refers to the present state of affairs. I devote more space to dawn than twilight, because one basic problem was there from the start, and by now those origins have been forgotten. Philosophers have learned many things about classification from the tradition of natural kinds. But now it is in disarray and (...) is unlikely to be put back together again. My argument is less founded on objections to the numerous theories now in circulation, than on the sheer proliferation of incompatible views. There no longer exists what Bertrand Russell called ‘the doctrine of natural kinds’—one doctrine. Instead we have a slew of distinct analyses directed at unrelated projects. (shrink)

There have been many attempts to determine what makes a natural kind real, chief among them is the criterion according to which natural kinds must be mind-independent. But it is difficult to specify this criterion: many supposed natural kinds have an element of mind-dependence. I will argue that the mind-independence criterion is nevertheless a good one, if correctly understood: the mind-independence criterion concerns the unification principles for natural kinds. Unification principles determine how (...) class='Hi'>natural kinds unify their properties, and only those natural kinds that have a mind-independent unification principle should be considered real. (shrink)

This paper addresses philosophical issues concerning whether mental disorders are natural kinds and how the DSM should classify mental disorders. I argue that some mental disorders (e.g., schizophrenia, depression) are natural kinds in the sense that they are natural classes constituted by a set of stable biological mechanisms. I subsequently argue that a theoretical and causal approach to classification would provide a superior method for classifying natural kinds than the purely descriptive approach adopted (...) by the DSM since DSM-III. My argument suggests that the DSM should classify natural kinds in order to provide predictively useful (i.e., projectable) diagnostic categories and that a causal approach to classification would provide a more promising method for formulating valid diagnostic categories. (shrink)

This paper discusses whether it can be known a priori that a particular term, such as water, is a natural kind term, and how this problem relates to Putnams claim that natural kind terms require an externalist semantics. Two conceptions of natural kind terms are contrasted: The first holds that whether water is a natural kind term depends on its a priori knowable semantic features. The second.

There are many ways of construing the claim that some categories are more “natural" than others. One can ask whether a system of categories is innate or acquired by learning, whether it pertains to a natural phenomenon or to a social institution, whether it is lexicalized in natural language or requires a compound linguistic expression. This renders suspect any univocal answer to this question in any particular case. Yet another question one can ask, which some authors take (...) to have a bearing on the issue of the naturalness of categories, is whether a system of categories constitutes a unique way of organizing a particular set of entities or phenomena, or whether there are other legitimate classification schemes that can coexist with it. Another way of putting this is by asking whether systems of categories can cut across one another, and if so, under what circumstances. Some philosophers have claimed that crosscutting systems of categories cannot exist as genuine natural kinds. This paper examines that claim and puts forward some counterexamples, concluding that this notion of natural kind is not in tune with scientific classification and ought to be rejected in favor of an alternative. (shrink)

A large part of our exploration of the world consists in categorizing or classifying the objects and processes we encounter, both in scientific and everyday contexts. There are various, perhaps innumerable, ways to sort objects into different kinds or categories, but it is commonly assumed that, among the countless possible types of classifications, one group is privileged. Philosophy refers to such categories as natural kinds. Standard examples of such kinds include fundamental physical particles, chemical elements, and (...) biological species. The term natural does not imply that natural kinds ought to categorize only naturally occurring stuff or objects. Candidates for natural kinds can include man-made substances, such as synthetic elements, that can be created in a laboratory. The naturalness in question is not the naturalness of the entities being classified, but that of the groupings themselves. Groupings that are artificial or arbitrary are not natural; they are invented or imposed on nature. Natural kinds, on the other hand, are not invented, and many assume that scientific investigations should discover them. (shrink)

What, for Kant, is the semantic status of the proposition: Water is H2O? Is it analytic or synthetic? The question is not one of merely esoteric import since an answer to it would constitute a statement about the meaningfulness of all our scientific propositions. And, insofar as the Critique is a defense of the possibility of the natural sciences, it seems that we should be able to find in it the answer to our question. Further, we should be able (...) to find an answer to the question of whether or not Kant is a scientific essentialist. I attempt to show that he is not an essentialist despite the fact that his semantics of natural kind terms greatly resembles that of some contemporary authors who are essentialists and take their semantic theories to provide evidence for their views. One way to go about this would be simply to locate Kant's criteria for the analytic/synthetic distinction and then to place the proposition in the category dictated by those criteria. Rather than employ this method, I will examine instead some of Kant's own examples. The hope is that by means of the examples the criteria themselves will achieve a greater degree of clarity and that through this clarification Kant's position will emerge as a genuine alternative to contemporary positions. (shrink)

Making use of our prescientific understanding of things, as well as relevant scientific theories, this book presents original arguments for monism with respect to the concept of a natural kind, for essentialism with respect to the members of a natural kind, and for natural-kinds realism with respect to a few chemical, physical, and biological kinds.

Recent challenges to non-traditional theories of natural kinds demand clarifications and revisions to those theories. Highlights: The semantics of natural kind terms is a special case of a general naturalistic conception of signaling in organisms that explains the epistemic reliability of signaling. Natural kinds and reference are two aspects of the same natural phenomenon. Natural kind definitions are phenomena in nature not linguistic or representational entities; their relation to conceptualized definitions is complex. Reference (...) and truth are special cases of a broader phenomenon of accommodation between aspects of signaling and epistemically relevant causal structures. (shrink)

This article explores the theory of natural kind essentialism, as developed by Putnam and Kripke. It defends the theory against certain criticisms, but also suggests that it should not be treated as universally true. Rather, it comes down to how different people use language, offering reasons why some people's idiolects might behave in an essentialist way while others behave in the contrary way, but explaining how we can all still communicate perfectly well despite this.

Natural kind essentialism is a specification of the intuitive idea that there are some mind-independent or objective categories in nature. These categories are thought to be characterised by a shared essence, which may involve intrinsic or extrinsic properties, mechanisms, or causal history. While the ontological basis of natural kinds has its roots in antiquity and especially Aristotle, the contemporary notion of a “natural kind” in philosophical discussion is often traced to William Whewell’s and John Stuart Mill’s (...) work in the 1800s. In its more modern form, natural kind essentialism was popularised in the 1970s mainly by Saul Kripke and Hilary Putnam. Traditionally, natural kind essentialism has been associated with intrinsic and microstructural properties, but contemporary work has made it clear that more refined versions of natural kind essentialism may have to accept extrinsic or relational essences. (shrink)

The new externalist picture of natural kind terms due to Kripke, Putnam, and others has become quite popular in philosophy. Many philosophers of science have remained sceptical. Häggqvist and Wikforss have recently criticised this view severely. They contend it depends essentially on a micro-essentialist view of natural kinds that is widely rejected among philosophers of science, and that a scientifically reasonable metaphysics entails the resurrection of some version of descriptivism. It is argued in this paper that the (...) situation is not quite as dark for the new theory of reference as many critics suggest. There are several distinct questions here which should not be conflated and ought to be dealt with one by one. Descriptivism remains arguably problematic. (shrink)

Philosophers have long been interested in a series of interrelated questions about natural kinds. What are they? What role do they play in science and metaphysics? How do they contribute to our epistemic projects? What categories count as natural kinds? And so on. Owing, perhaps, to different starting points and emphases, we now have at hand a variety of conceptions of natural kinds—some apparently better suited than others to accommodate a particular sort of inquiry. (...) Even if coherent, this situation isn’t ideal. My goal in this article is to begin to articulate a more general account of ‘natural kind phenomena’. While I do not claim that this account should satisfy everyone—it is built around a certain conception of the epistemic role of kinds and has an obvious pragmatic flavour—I believe that it has the resources to go further than extant alternatives, in particular the homeostatic property cluster view of kinds. (shrink)

In _Realism and Naturalizing Knowledge_ (Keisho Shobo, 2013), Ryo Uehara carefully formulates the homeostatic property cluster theory of natural kinds and expands it by applying this framework to artifacts and knowledge and thereby drawing them in the naturalistic picture of the world. This is a substantial addition to the development of naturalistic philosophy in Japan. In this essay I shall make general comments on his account of natural kinds in the following respects: Uehara's distinction between real (...) and nominal kinds, his objection to the species-as-individual thesis, the relative lack of attention to the distinction between the realism of natural kinds and the scientific realism, and finally, races as possible natural kinds. (shrink)

I argue for the importance of clarifying the distinction between metaphysical, semantic, and meta-semantic concerns regarding what Emotion is. This allows us to see that those involved in the Scientific Emotion Project and the Folk Emotion Project are in fact involved in the same project – the Science of Emotion. It also helps us understand why questions regarding the natural kind status of Emotion, as well as answers to questions regarding the value of ordinary language emotion terms or concepts (...) to emotion research, will not help resolve the observed crisis in the Science of Emotion. (shrink)

This paper considers the problem of assigning meanings to empty natural kind terms. It does so in the context of the Twin-Earth externalist-internalist debate about whether the meanings of natural kind terms are individuated by the external physical environment of the speakers using these terms. The paper clarifies and outlines the different ways in which meanings could be assigned to empty natural kind terms. And it argues that externalists do not have the semantic resources to assign them (...) meanings. The paper ends on a sceptical note concerning the fruitfulness of using the Twin-Earth setting in debates about the semantics of empty natural kind terms. (shrink)

According to the received tradition, the language used to to refer to natural kinds in scientific discourse remains stable even as theories about these kinds are refined. In this illuminating book, Joseph LaPorte argues that scientists do not discover that sentences about natural kinds, like 'Whales are mammals, not fish', are true rather than false. Instead, scientists find that these sentences were vague in the language of earlier speakers and they refine the meanings of the (...) relevant natural-kind terms to make the sentences true. Hence, scientists change the meaning of these terms, This conclusions prompts LaPorte to examine the consequences of this change in meaning for the issue of incommensurability and for the progress of science. This book will appeal to students and professional in the philosophy of science, the philosophy of biology and the philosophy of language. (shrink)

The identity of a natural kind can be construed in terms of its causal profile. This conception is more appropriate to science than two alternatives. The identity of a natural kind is not determined by one causal role because one natural kind can have many causal roles and several functions and because some functions are shared by different kinds. Furthermore, the microstructuralist thesis is wrong: The identity of certain natural kinds is not determined by (...) their microstructure. It is true that if A and B have the same microstructural composition then a sample of a chemical substance A is of the same chemical substance as a sample of B. However, the reverse does not hold. It is not the case that if a sample of a chemical substance A is of the same chemical substance as a sample of B then A and B have the same microstructural composition. This is because a macroscopic NK can be “multiconstituted” by different microstructures. (shrink)

Paradigmatically, natural kinds are the kinds of thing or stuff that are classified by the natural sciences. The periodic table provides perhaps the best example of the potential importance of natural kinds for science. In the philosophy of psychiatry, debates over whether mental disorders can be natural kinds emerge because kinds of mental disorder are manifestly different from chemical kinds in various ways. While chemical kinds are precise, psychiatric (...) class='Hi'>kinds are fuzzy. While chemical kinds are objective, the identification of psychiatric kinds is value-laden. Psychiatric classification involves classifying people, and unlike chemical elements, those people can respond to being classified in various ways. This chapter goes through these differences, one-by-one, and argues that despite them, mental disorders may be natural kinds. (shrink)

Naturalism about natural kinds is the view that they are none other than the kinds discoverable by science. This thesis is in tension with what is perhaps the dominant contemporary view of natural kinds: essentialism. According to essentialism, natural kinds constitute a small subset of our scientific categories, namely those definable in terms of intrinsic, microphysical properties, which are possessed necessarily rather than contingently by their bearers. Though essentialism may appear compatible with naturalism, (...) and is indeed sometimes qualified with the epithet “scientific,” it has become increasingly clear in recent years that only a minority of categories posited by science satisfy those conditions. I will not try to argue against essentialism directly in this chapter. Instead, I will attempt to articulate an alternative, naturalist conception of natural kinds, according to which the mark of natural kinds is their discoverability by science, not just basic science but the special sciences and even the social sciences. (shrink)

The aim of this article is to illustrate how a belief in the existence of kinds may be justified for the particular case of natural kinds: particularly noteworthy in this respect is the weight borne by scientific natural kinds (e.g., physical, chemical, and biological kinds) in (i) inductive arguments; (ii) the laws of nature; and (iii) causal explanations. It is argued that biological taxa are properly viewed as kinds as well, despite the fact (...) that they have been by some alleged to be individuals. Since it turns out that the arguments associated with the standard Kripke/Putnam semantics for natural kind terms only establish the non-descriptiveness of natural kind terms and not their rigidity, the door is open to analyze these terms as denoting traditional predicate-extensions. Finally, special issues raised by physical and chemical kinds are considered briefly, in particular impurities, isotopes and the threat of incommensurability. (shrink)

Theoretical identity statements of the form "water is H2O‟ are allegedly necessary truths knowable a posteriori, and assert that nothing could be water and not be H2O. The necessary a posteriori nature of these identity claims has been taken by Kripke, Putnam and Donnellan to justify a move from talk of reference (language) to talk of essence (metaphysics), and has motivated much of contemporary essentialism. In this paper I will contest this move from reference to essence, and argue that (i.) (...) the only way to derive essentialism from semantics (specifically direct reference) is to assume it as a premise, (ii.) that contemporary essentialism is a metaphysical assumption not a thesis, and (iii.) – assuming the accuracy of the analogy between proper names and natural kind terms – present an alternative version of natural kinds classification that is interest-relative, dependent on practical application and reflects the contingent state of affairs which is our world. (shrink)

Recently in the philosophy of psychology it has been suggested that several putative phenomena such as emotions, memory, or concepts are not genuine natural kinds and should therefore be eliminated from the vocabulary of scientific psychology. In this paper I examine the perhaps most well known case of scientific eliminativism, Edouard Machery’s concept eliminativism. I argue that the split-lump-eliminate scheme of con- ceptual change underlying Machery’s eliminativist proposal assumes a simplistic view of the functioning of scientific concepts. Conceiving (...) of scientific concepts as natural kind terms is an important reason for the impasse between Machery and anti-eliminativists, as both sides allude to properties of natural kinds in their contradicting arguments. As a solution I propose that, in order to develop a more satisfactory theory of conceptual change in science, one needs to distinguish between three different types of scientific concepts, hitherto conflated under the loaded notion of natural kind. (shrink)

This paper asks when a natural disease kind is truly 'reactive' and when it is merely associated with a corresponding social kind. I begin with a permissive account of real kinds and their structure, distinguishing natural kinds, indifferent kinds and reactive kinds as varieties of real kind characterised by super-explanatory properties. I then situate disease kinds within this framework, arguing that many disease kinds prima facie are both natural and reactive. I (...) proceed to distinguish ‘simple dependence’, ‘secondary dependence’ and ‘essential dependence’ between a natural kind and its classification, and argue that a natural kind is only really reactive, in an important sense, under conditions of essential dependence. On this basis, I offer a principled hypothesis for why psychiatric kinds tend to be more metaphysically unstable than paradigm somatic disease kinds. (shrink)

Marc Lange and Ann Whittle have independently developed an important challenge to dispositionalism, arguing that dispositions are reducible to primitive subjunctive facts. I argue in reply that by pairing dispositionalism with a certain version of natural-kind essentialism, their objection can be overcome. Moreover, such a marriage carries further advantages for the dispositionalist. My aim is therefore two-fold: to defend dispositionalism, and to give the dispositionalist some new motivation to adopt natural-kind essentialism.

It is commonly assumed that natural kind terms constitute a distinct semantic category. This idea emerged during the 1970's following Kripke's and Putnam's well-known remarks on natural kind terms. The idea has stayed with us, although it is now recognized that the issues are considerably more complex than initially thought. Thus, it has become clear that much of Kripke's and Putnam's discussions were based on rather simplified views of natural kinds. It also turns out that the (...) semantic issues are less straightforward than assumed - in particular, it is far from clear what it might mean to say that a kind term is rigid. Strikingly, however, these worries have not done much to undermine the confident assumption that natural kind terms form a special semantic category. In the paper I try to shake that confidence. I argue that although natural kind terms are no doubt important (for instance, from an explanatory point of view), we are certainly not warranted in concluding that they form a separate, semantic category among the kind terms. (shrink)

Theoreticians that defend a form of realism regarding natural kinds minimally entertain the belief that the world features divisions into kinds and that the natural kind concept is a useful tool for philosophy of science. The objective of this paper is to challenge these assumptions. First, we challenge realism toward natural kinds by showing that the main arguments for their existence, which rely on the epistemic success of natural kinds, are unsatisfactory. Second, (...) we show that, whether they exist or not, natural kinds are expendable when it comes to describing and analyzing scientific explanations accurately. (shrink)

This paper evaluates the Natural-Kinds Argument for cognitive extension, which purports to show that the kinds presupposed by our best cognitive science have instances external to human organism. Various interpretations of the argument are articulated and evaluated, using the overarching categories of memory and cognition as test cases. Particular emphasis is placed on criteria for the scientific legitimacy of generic kinds, that is, kinds characterized in very broad terms rather than in terms of their fine-grained (...) causal roles. Given the current state of cognitive science, I conclude that we have no reason to think memory or cognition are generic natural kinds that can ground an argument for cognitive extension. (shrink)

Recent experimental studies have claimed to find evidence for the view that natural kind terms such as “water” are ambiguous: that they have two extensions, one determined by superficial properties, the other by underlying essence. In an online experiment, we presented to 600 participants scenarios describing discoveries of novel samples that differ in deep structure from samples of a familiar kind but are superficially identical, such as a water-like substance that is not composed of H2O. We used three different (...) types of question sets to probe whether the participants considered the sample as a member of the kind or not. Our results did not confirm the predictions of the ambiguity view. They were, rather, consistent with views that take underlying essences to be the sole criterion for membership in a natural kind. (shrink)

It is commonly held that objects in the world form natural kinds. Rabbits form a natural kind and so do all pieces of gold. The traditional account of natural kinds asserts that the members of a kind share a common essence. The essence of gold, for example, is its unique atomic structure. That structure occurs in all and only pieces of gold, and it is a property that all pieces of gold must have.

A standard requirement on natural kinds is that they be mind independent. However, many kinds in the human and social sciences, even the natural sciences, depend on human thought. This article suggests that the mind independence requirement on natural kinds be replaced with the requirement that natural kind classifications be defeasible. The defeasibility requirement does not require that natural kinds be mind independent, so it does not exclude mind dependent scientific (...) class='Hi'>kinds from being natural kinds. Furthermore, the defeasibility requirement captures the idea that natural kind classifications are tools for investigating the empirical world. (shrink)

What accounts for the linkage of seemingly diverse and inherently separable fundamental properties, such that they are regarded as properties of a single thing? Multiple answers to this question have been put forward in both the historical and current literature, especially from competing substance ontologies and competing theories concerning the metaphysics of natural kinds. Here I lay out and critically assess two ways in which dispositionalism might contribute to the discussion.

In this paper, I focus on life-threatening medical conditions and argue that from the point of view of natural properties, induction(s), and participation in laws, at least some of the ill organisms dealt with in somatic medicine form natural kinds in the same sense in which the kinds in the exact sciences are thought of as natural. By way of comparing two ‘divisions of nature’, viz., a ‘classical’ exact science kind (gold) and a kind of (...) disease (Graves disease), I show that there is no justifiable ‘ontological gap’ between disease kinds and exact sciences kinds. We have instead a difference of degree. (shrink)

Most contemporary analytic philosophers of language and mind accept the view that there is a wide class of terms, “natural kind terms”, which includes names of substances (the most common example is “water”), of species of animals, and of many other kinds of things in nature, whose meaning and reference is determined in the way explained by the theory developed in the 1970s by Saul Kripke and Hilary Putnam. The theory is often referred to as “the Kripke-Putnam theory” (...) and is supposed to have such achievements as the overthrow of the earlier dominant Fregean theory of word-meanings (dubbed “descriptivism” by Kripke) as determined by the concepts in our minds, providing support for the “externalist” approach to linguistic meanings (in line with Putnam’s claim that “"Meanings" just ain’t in the head”), and the discovery that there is a wide class of truths (such as that water is H20) that are both a posteriori and necessary. Although the priority in the development of this theory belongs to Kripke, it could hardly gain such a wide acceptance without contributions by Putnam, which turned out to be very influential. However, the habitual idea of “the Kripke-Putnam theory”, as one theory, tends to play down the differences between Putnam’s and Kripke’s approaches and to hush up the fact that in his late works, of 1983 and 1990, Putnam revised and abandoned pretty much of his “Kripkean” views of 1970-ies; in particular, repudiated the pride of Kripke’s theory, the idea of necessary a posteriori truths. This article makes critical analysis and evaluation of Putnam’s ideas and arguments usually credited as important contributions to “the Kripke-Putnam theory”, and highlights the main points of the revision in late Putnam’s works. The case is made that Putnam's famous argument for externalism about meanings, the Twin-Earth thought experiment, is question-begging, fails to do justice to likely changes in the meanings of words with the development of knowledge, and conflicts with the linguistic practice in the relevantly similar case of “jade”. Putnam's argument for externalism from the division of linguistic labour is not cogent too, because “semantic deference” is itself a matter of what is there in “heads” - of some (non-expert) heads deferring to other (recognised as expert) heads. Eventually, on close inspection and in the light of Putnam's later reexplanation and revision, his account of meaning and reference turns out to be a sophisticated variety of conceptualism/internalism. (shrink)

Objects have dispositions. Dispositions are normally analyzed by providing a meaning to disposition ascriptions like ‘This piece of salt is soluble’. Philosophers like Carnap, Goodman, Quine, Lewis and many others have proposed analyses of such disposition ascriptions. In this paper we will argue with Quine that the proper analysis of ascriptions of the form ‘x is disposed to m ’, where ‘x’ denotes an object, ‘m’ a manifestation, and ‘C’ a condition, goes like this: ‘x is of natural kind (...) k’, and the generic ‘ks are m ’ is true. For the analysis of the generic, we propose an analysis in terms of causal powers: ‘ks have the causal power to m’. The latter, in turn, is analyzed in a very precise way, making use of Pearl’s probabilistic graphical causal models. We will show how this natural kind-analysis improves on standard conditional analyses of dispositions by avoiding the standard counterexamples, and that it gives rise to precise observable criteria under which the disposition ascription is true. (shrink)

Essentialism--understood as the doctrine that there are natural kinds--can be sustained with respect to the most fundamental physical entities of the world, as I elsewhere argue. In this paper I take up the question of the existence of natural kinds among complex structures built out of these elementary ones. I consider a number of objections to essentialism, in particular Locke's puzzle about the existence of borderline cases. A number of recent attempts to justify biological taxonomy are (...) critically examined. I conclude that theory partially justifies such taxonomies but supports only a weaker form of essentialism. (shrink)

A paradigmatic case of rigidity for singular terms is that of proper names. And it would seem that a paradigmatic case of rigidity for general terms is that of natural kind terms. However, many philosophers think that rigidity cannot be extended from singular terms to general terms. The reason for this is that rigidity appears to become trivial when such terms are considered: natural kind terms come out as rigid, but so do all other general terms, and in (...) particular all descriptive general terms. This paper offers an account of rigidity for natural kind terms which does not trivialise in this way. On this account, natural kind terms are de jure obstinately rigid designators and other general terms, such as descriptive general terms, are not. (shrink)

The aim of this paper is to provide a complete Natural Kind Semantics for an Essentialist Theory of Kinds. The theory is formulated in two-sorted first order monadic modal logic with identity. The natural kind semantics is based on Rudolf Willes Theory of Concept Lattices. The semantics is then used to explain several consequences of the theory, including results about the specificity (species–genus) relations between kinds, the definitions of kinds in terms of genera and specific (...) differences and the existence of negative kinds. First, I show under which conditions the Hierarchy principle, which has been subjected to counterexamples in the literature, holds. I also show that a different principle about the species–genus relations between kinds, namely Kant’s Law, follows from the essentialist theory. Second, I introduce two new operations for kinds and show that they can be used to provide traditional definitions of kinds in terms of genera and specific differences. Finally, I show that these operations of specific difference induce, for each kind, a uniquely specified contrary kind and a uniquely specified subcontrary kind, which can be used as semantic values for non-classical predicate negations of kind terms. (shrink)

Philosophical treatments of natural kinds are embedded in two distinct projects. I call these the philosophy of science approach and the philosophy of language approach. Each is characterized by its own set of philosophical questions, concerns, and assumptions. The kinds studied in the philosophy of science approach are projectible categories that can ground inductive inferences and scientific explanation. The kinds studied in the philosophy of language approach are the referential objects of a special linguistic category—natural (...) kind terms—thought to refer directly. Philosophers may hope for a unified account addresses both sets of concerns. This paper argues that this cannot be done successfully. No single account can satisfy both the semantic objectives of the philosophy of language approach and the explanatory projects of the philosophy of science approach. After analyzing where the tensions arise, I make recommendations about assumptions and projects that are best abandoned, those that should be retained, and those that should go their separate ways. I also recommend adopting the disambiguating terminology of “scientific kinds” and “natural kinds” for the different notions of kinds developed in these different approaches. (shrink)

This paper maps the landscape for a range of views concerning the metaphysics of natural kinds. I consider a range of increasingly ontologically committed views concerning natural kinds and the possible arguments for them. I then ask how these relate to natural kind essentialism, arguing that essentialism requires commitment to kinds as entities. I conclude by examining the homeostatic property cluster view of kinds in the light of the general understanding of kinds (...) developed. (shrink)