What are biological species? Aristotelians and Lockeans agree that they are natural kinds; but, evolutionary theory shows that neither traditional philosophical approach is truly adequate. Recently, Michael Ghiselin and David Hull have argued that species are individuals. This claim is shown to be against the spirit of much modern biology. It is concluded that species are natural kinds of a sort, and that any 'objectivity' they possess comes from their being at the focus of a consilience (...) of inductions. (shrink)

What are biological species? Aristotelians and Lockeans agree that they are natural kinds; but, evolutionary theory shows that neither traditional philosophical approach is truly adequate. Recently, Michael Ghiselin and David Hull have argued that species are individuals. This claim is shown to be against the spirit of much modern biology. It is concluded that species are natural kinds of a sort, and that any 'objectivity' they possess comes from their being at the focus of a consilience (...) of inductions. (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)

The fact that the names of biological species refer independently of identifying descriptions does not support the view of Ghiselin and Hull that species are individuals. Species may be regarded as natural kinds whose members share an essence which distinguishes them from the members of other species and accounts for the fact that they are reproductively isolated from the members of other species. Because evolutionary theory requires that species be spatiotemporally localized their names cannot occur in scientific laws. (...) If natural kind status is denied to species on this ground, it must also be denied to most classes of concrete entities which are now accorded such status. (shrink)

This paper argues that typical biological species are natural kinds, on a familiar realist understanding of natural kinds—classes of individuals across which certain properties cluster together, in virtue of the causal workings of the world. But the clustering is far from exceptionless. Virtually no properties, or property-combinations, characterize every last member of a typical species—unless they can also appear outside the species. This motivates some to hold that what ties together the members of a species is (...) the ability to interbreed, others that it is common descent. Yet others hold that species are scattered individuals,of which organisms are parts rather than members. But not one of these views absolves us of the need to posit a typical phenotypic profile. Vagueness is here to stay. Some seek to explain the vagueness by saying species are united by “homeostatic property clusters”; but this view collapses into the more familiar realist picture. (shrink)

The traditional practice of establishing morphological types and investigating morphological organization has found new support from evolutionary developmental biology (evo-devo), especially with respect to the notion of body plans. Despite recurring claims that typology is at odds with evolutionary thinking, evo-devo offers mechanistic explanations of the evolutionary origin, transformation, and evolvability of morphological organization. In parallel, philosophers have developed non-essentialist conceptions of natural kinds that permit kinds to exhibit variation and undergo change. This not only facilitates a (...) construal of species and higher taxa as natural kinds, but also broadens our perspective on the diversity of kinds found in biology. There are many different natural kinds relevant to the investigative and explanatory aims of evo-devo, including homologues and developmental modules. (shrink)

A major issue in philosophical debates on the species problem concerns the opposition between two seemingly incompatible views of the metaphysics of species: the view that species are individuals and the view that species are natural kinds. In two recent papers in this journal, Olivier Rieppel suggested that this opposition is much less deep than it seems at first sight. Rieppel used a recently developed philosophical account of natural kindhood, namely Richard Boyd’s “homeostatic property cluster” theory, to (...) argue that every species taxon can be conceived of as an individual that constitutes the single member of its own specific natural kind. In this paper I criticize Rieppel’s approach and argue that it does not deliver what it is supposed to, namely an account of species as kinds about which generalized statements can be made. (shrink)

It has been widely argued that words are analogous to species such that words, like species, are natural kinds. In this paper, I consider the metaphysics of word-kinds. After arguing against an essentialist approach, I argue that word-kinds are homeostatic property clusters, in line with the dominant approach to other biological and psychological kinds.

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)

Despite the traditional focus on metaphysical issues in discussions of natural kinds in biology, epistemological considerations are at least as important. By revisiting the debate as to whether taxa are kinds or individuals, I argue that both accounts are metaphysically compatible, but that one or the other approach can be pragmatically preferable depending on the epistemic context. Recent objections against construing species as homeostatic property cluster kinds are also addressed. The second part of the paper broadens (...) the perspective by considering homologues as another example of natural kinds, comparing them with analogues as functionally defined kinds. Given that there are various types of natural kinds, I discuss the different theoretical purposes served by diverse kind concepts, suggesting that there is no clear-cut distinction between natural kinds and other kinds, such as functional kinds. Rather than attempting to offer a unique metaphysical account of ‘natural’ kind, a more fruitful approach consists in the epistemological study of how different natural kind concepts are employed in scientific reasoning. (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)

The traditional home for the concept of a natural kind in biology is of course taxonomy, the sorting of organisms into a nested hierarchy of kinds. Many taxonomists and most philosophers of biology now deny that it is possible to sort organisms into natural kinds. Many do not think that biological taxonomy sorts them into kinds at all, but rather identifies them as parts of historical individuals. But at any rate if the species, genera and (...) so on of biological taxonomy are kinds at all, there are various respects in which they fall short of the traditional requirements of naturalness. The members of biological taxa lack essential properties that make them members of a particular kind: any properties specific enough to belong only to members of the kind cannot be assumed to belong to all members of the kind. And if there are laws applying to members of biological taxa they are laws of very minor and local importance and, in view of the preceding point, at best probabilistic. (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)

Traditional debate on the metaphysics of gender has been a contrast of essentialist and social-constructionist positions. The standard reaction to this opposition is that neither position alone has the theoretical resources required to satisfy an equitable politics. This has caused a number of theorists to suggest ways in which gender is unified on the basis of social rather than biological characteristics but is “real” or “objective” nonetheless – a position I term social objectivism. This essay begins by making explicit the (...) motivations for, and central assumptions of, social objectivism. I then propose that gender is better understood as a real kind with a historical essence, analogous to the biologist’s claim that species are historical entities. I argue that this proposal achieves a better solution to the problems that motivate social objectivism. Moreover, the account is consistent with a post-positivist understanding of the classificatory practices employed within the natural and social sciences. (shrink)

A long-standing debate has dominated systematic biology and the ontological commitments made by its theories. The debate has contrasted individuals and the part – whole relationship with classes and the membership relation. This essay proposes to conceptualize the hierarchy of higher taxa is terms of a hierarchy of homeostatic property cluster natural kinds (biological species remain largely excluded from the present discussion). The reference of natural kind terms that apply to supraspecific taxa is initially fixed descriptively; the (...) extension of those natural kind terms is subsequently established by empirical investigation. In that sense, classification precedes generalization, and description provides guidance to empirical investigation. The reconstruction of a hierarchy of (homeostatic property cluster) natural kinds is discussed in the light of cladistic methods of phylogeny reconstruction. (shrink)

Talk of different types of cells is commonplace in the biological sciences. We know a great deal, for example, about human muscle cells by studying the same type of cells in mice. Information about cell type is apparently largely projectible across species boundaries. But what defines cell type? Do cells come pre-packaged into different natural kinds? Philosophical attention to these questions has been extremely limited [see e.g., Wilson (Species: New Interdisciplinary Essays, pp 187–207, 1999; Genes and the Agents (...) of Life, 2005; Wilson et al. Philos Top 35(1/2):189–215, 2007)]. On the face of it, the problems we face in individuating cellular kinds resemble those biologists and philosophers of biology encountered in thinking about species: there are apparently many different (and interconnected) bases on which we might legitimately classify cells. We could, for example, focus on their developmental history (a sort of analogue to a species’ evolutionary history); or we might divide on the basis of certain structural features, functional role, location within larger systems, and so on. In this paper, I sketch an approach to cellular kinds inspired by Boyd’s Homeostatic Property Cluster Theory, applying some lessons from this application back to general questions about the nature of natural kinds. (shrink)

This chapter discusses issues regarding realism, specifically the realism issues in biology. The discussion starts with an issue that arises from the debate between “species monists” who argue that there exists only one good “species concept” and “species pluralists” who insist that there are many. The various species concepts are then summarized and the motivation for pluralism outlined. An overview of realism is provided here, specifically, of a“realism about the external world.” Finally, the central question, focusing on the apparent clash (...) between Marc Ereshefsky’s “pluralistic antirealism” and Philip Kitcher’s “pluralistic realism,” is addressed. The chapter concludes by considering “realism” issues about genera and higher categories in the Linnaean hierarchy. (shrink)

Biological species are often taken as counterexamples to essentialist accounts of natural kinds. Essentialists like Ellis (2001) agree with nominalists that because biological kinds evolve, any distinctions between kinds of biological kind must ultimately be arbitrary. The resulting vagueness in the extension of natural kind predicates in the case of species has led to the claim that species ought to be construed as individuals rather than kinds (Ghiselin 1974, 1987; Hull 1976, 1978). I examine (...) the possibility that causal features extrinsic to the properties of natural kinds are responsible for establishing the unity of the properties of a natural kind. I reject the intuitive idea that laws of nature might act as such an external mechanism because this would entail an account of ceteris paribus biological laws, where there are no plausible truthmakers in terms of kinds or properties. I suggest instead that symbiosis is a plausible external causal mechanism, which explains the evolution of homeostasis in natural kind clusters. This involves the acceptance of an expanded account of evolutionary development as cooperative symbiosis. (shrink)

This paper takes a hierarchical approach to the question whether species are individuals or natural kinds. The thesis defended here is that species are spatiotemporally located complex wholes (individuals), that are composed of (i.e., include) causally interdependent parts, which collectively also instantiate a homeostatic property cluster (HPC) natural kind. Species may form open or closed genetic systems that are dynamic in nature, that have fuzzy boundaries due to the processual nature of speciation, that may have leaky boundaries (...) as is manifest in lateral gene transfer and introgression, that may be of multiple origins through hybridization, and that may split and merge and split again over time. The identity conditions of species qua individuals will have to be anchored in their history, rather than in their unique evolutionary origin. Species qua historically conditioned HPC natural kinds requires the kind to be mereologically structured, subject to the part-whole relation rather than the membership relation. This implies that there can be more than one kind of natural kinds. (shrink)

The claim is frequently made that structured collections of individuals who are themselves subjects of mental and cognitive states – such collections as courts, countries, and corporations – can be, and often are, subjects of mental or cognitive states. And, to be clear, advocates for this so-called group-minds hypothesis intend their view to be interpreted literally, not metaphorically. The existing critical literature casts substantial doubt on this view, at least on the assumption that groups are claimed to instantiate the same (...) species of mental and cognitive properties as individual humans. In this essay, I evaluate a defensive move made by some proponents of the group-oriented view: to concede that group states and individual states aren’t of the same specific natural kinds, while holding that groups instantiate different species of mental or cognitive states – perhaps a different species of cognition itself – from those instantiated by humans. In order to evaluate this defense of group cognition, I develop a view of natural kinds – or at least of the sort of evidence that supports inferences to the sameness of natural kind – a view I have previous dubbed the ‘tweak-and-extend’ theory. Guided by the tweak-and-extend approach, I arrive at a tentative conclusion: that what is common to models of individual cognitive processing and models of group processing does not suffice to establish sameness of cognitive (or mental) kinds, properties, or state-types, not even at a generic or overarching level. (shrink)

Asking whether the sexes are natural kinds amounts to asking whether the categories, female and male, identify real divisions in nature, like the distinctions between biological species, or whether they mark merely artificial or arbitrary distinctions. The distinction between females and males in the animal kingdom is based on the relative size of the gametes they produce, with females producing larger gametes (ova) and males producing smaller gametes (sperm). This chapter argues that the properties of producing relatively large (...) and small gametes are causally correlated with a range of other properties in a wide variety of organisms, and this is what makes females and males natural kinds in the animal kingdom. The chapter concludes with a discussion of the relationship between sex and gender: while the difference between the sexes is biologically grounded, the difference between genders is socially based. Since gender depends in part on the perception of sex, whether or not gender is real or not does not depend on whether sex is, since social reality is constituted in part by our perceptions. The claim that sexes are natural kinds in the animal kingdom does not imply that the biological differences among female and male humans do and should have social consequences. (shrink)

The vision of natural kinds that is most common in the modern philosophy of biology, particularly with respect to the question whether species and other taxa are natural kinds, is based on a revision of the notion by Mill in A System of Logic. However, there was another conception that Whewell had previously captured well, which taxonomists have always employed, of kinds as being types that need not have necessary and sufficient characters and properties, or (...) essences. These competing views employ different approaches to scientific methodologies: Mill’s class-kinds are not formed by induction but by deduction, while Whewell’s type-kinds are inductive. More recently, phylogenetic kinds (clades, or monophyletic-kinds) are inductively projectible, and escape Mill’s strictures. Mill’s version represents a shift in the notions of kinds from the biological to the physical sciences. (shrink)

A minimal second order modal logic of natural kinds is formulated. Concepts are distinguished from properties and relations in the conceptual-logistic background of the logic through a distinction between free and bound predicate variables. Not all concepts (as indicated by free predicate variables) need have a property or relation corresponding to them (as values of bound predicate variables). Issues pertaining to identity and existence as impredicative concepts are examined and an analysis of mass terms as nominalized predicates for (...) kinds of stuff is proposed. The minimal logic is extendible through a summum genus, an infima species or a partition principle for natural kinds. (shrink)

Recent rival attempts in the philosophy of science to put forward a general theory of the properties that all (and only) natural kinds across the sciences possess may have proven to be futile. Instead, I develop a general methodological framework for how to philosophically study kinds. Any kind has to be investigated and articulated together with the human aims that motivate referring to this kind, where different kinds in the same scientific domain can answer to different (...) concrete aims. My core contention is that non-epistemic aims, including environmental, ethical, and political aims, matter as well. This is defended and illustrated based on several examples of kinds, with particular attention to the role of social-political aims: species, race, gender, as well as personality disorders and oppositional defiant disorder as psychiatric kinds. Such non-epistemic aims and values need not always be those personally favoured by scientists, but may have to reflect values that matter to relevant societal stakeholders. Despite the general agenda to study ‘kinds,’ I argue that philosophers should stop using the term ‘natural kinds,’ as this label obscures the relevance of humans interests and the way in which many kinds are based on contingent social processes subject to human responsibility. (shrink)

According to the well-known Kripke-Putnam view developed in Naming and Necessity and ‘The Meaning of Meaning’, proper names and ‘natural kind terms’ - words for natural substances, species, and phenomena - are non-descriptional and rigid. A singular term is rigid if it has the same referent in every possible world, and is non-descriptional if, roughly speaking, its referent is not secured by purely descriptive conditions analytically tied to the term. Thus, ‘the inventor of bifocals’ is nonrigid and descriptional, (...) while ‘the unique even and prime integer’ is rigid and descriptional, and ‘Noam Chomsky’ is rigid and non-descriptional. (shrink)

The two opinions concerning real essences that Locke mentions in III.iii.17 represent competing theories about the way in which naturally occurring objects are divided into species. In this paper I explain what these competing theories amount to, why he denies the theory of kinds that is embodied in the first of these opinions, and how this denial is related to his general critique of essentialism. I argue first, that we cannot meaningfully ask whether Locke accepts the existence of (...) class='Hi'>natural kinds, per se, since he affirms the theory of kinds that is embodied in the second opinion, while he denies the theory that is embodied in the first opinion. Second, I show that his denial of this theory is not solely or even primarily directed against the scholastic/Aristotelian theory of substantial forms, since he is most interested in refuting a corpuscularian version of this theory. And third, I argue that Locke’s anti-essentialism does not follow solely from his denial of (deeply objective) natural kinds, since one could consistently make this denial and affirm the existence of de re essential properties. (shrink)

The two opinions concerning real essences that Locke mentions in III.iii.17 represent competing theories about the way in which naturally occurring objects are divided into species. In this paper I explain what these competing theories amount to, why he denies the theory of kinds that is embodied in the first of these opinions, and how this denial is related to his general critique of essentialism. I argue first, that we cannot meaningfully ask whether Locke accepts the existence of (...) class='Hi'>natural kinds, per se, since he affirms the theory of kinds that is embodied in the second opinion, while he denies the theory that is embodied in the first opinion. Second, I show that his denial of this theory is not solely or even primarily directed against the scholastic/Aristotelian theory of substantial forms, since he is most interested in refuting a corpuscularian version of this theory. And third, I argue that Locke’s anti-essentialism does not follow solely from his denial of (deeply objective) natural kinds, since one could consistently make this denial and affirm the existence of de re essential properties. (shrink)

This article is an introduction to the Synthese Special Issue, Natural Kinds: Language, Science, and Metaphysics. The issue includes new contributions to some of the main questions involved in the present philosophical debates on natural kinds and on natural kind terms. Those debates are relevant to philosophy of language, philosophy of science, and metaphysics. In philosophy of language it is highly debated what the meaning of natural kind terms is, how their reference is determined, (...) as well as whether there are differences and similarities between the semantics of natural kind terms and that of other sorts of kind terms. In philosophy of science, natural kinds are relevant because they are the basis for scientific classifications and play an explanatory role in scientific theories; thus one aim of science is to discover natural kinds and theorize about them. Natural kinds are also relevant in metaphysics, where many questions involving natural kinds are debated and especially those concerning the sort of entities we refer to when using natural kind terms, i.e., the ontological status of natural kinds; in this regard there are different views, such as conventionalism, realism and essentialism. Another metaphysical question is what it is that characterizes the naturalness of kind divisions. The introduction sketches the antecedents of some of the present views on natural kinds and natural kind terms, and indicates some of the topics dealt with in the articles that make up the issue, which can be classified in the following groups: the metaphysics and epistemology of natural kinds the semantics of natural kind terms and other kind terms questions on species and other related issues on natural kinds. However, many of the articles cover more than just one of these topics. (shrink)

In chapter 1 it is argued that species and other biological taxa are natural kinds. This view is defended against accounts according to which biological taxa are not kinds at all, but individuals, and against accounts according to which biological taxa are kinds but not natural. With regard to, LaPorte argues for the minimalist position that both the species-as-individuals interpretation as well as the species-as-kinds interpretation can be viewed as an adequate reconstruction of scientific (...) species-talk. With regard to, he first adopts the liberal conception that a natural kind is a kind with explanatory value—thus allowing for naturalness to come in degrees and respects—and he then shows that, unsurprisingly, biological kinds qualify as natural. (shrink)

According to John Searle, money is an institutional entity; it is among the things “that exist only because we believe them to exist”. I believe that Searle’s view is correct in some important respects. At the same time, I argue that money is a real or natural kind, much in the same way as biological species or chemical substances are real kinds about which empirical knowledge can be accumulated. The paper attempts to show the consistency of these assumptions. (...) My argument proceeds in two steps. First, I introduce homeostatic property cluster theory and characterize it as the most adequate account of real kinds that has been developed so far. Second, I reexamine, and to some extent reinterpret, money – one of Searle’s central examples of an institutional kind – and argue that it meets the conditions of a real kind as stated by HPC theory. An important part of the argument is a reconsideration of the circularity problem, i.e., the problem that Searle’s way of analyzing money already seems to presuppose the concept of money. (shrink)

One of the more interesting topics debated by Leibniz and Locke and one that has received comparatively little critical commentary is the nature of essences and the classification of the natural world.1 This topic, moreover, is of tremendous importance, occupying a position at the intersection of the metaphysics of individual beings, modality, epistemology, and philosophy of language. And, while it goes back to Plato, who wondered if we could cut nature at its joints, as Nicholas Jolley has pointed out, (...) the debate between Leibniz and Locke has very clear similarities to the topic that has dominated the philosophy of language from the 1970s on: namely, the challenge mounted by Kripke, Kaplan, Putnam, and others against Russellian and Fregean descriptivist accounts of meaning. Yet, this topic is also, as Jolley writes, one of the “most elusive” in the debate between Leibniz and Locke.2 The purpose of this paper is to examine in detail Leibniz’s critique of Locke’s distinction between real and nominal essences. In doing so, I hope to show certain virtues in Leibniz’s account of metaphysics and philosophy of language that usually escape notice. While I wish to provide a general account of Leibniz’s disagreement with Locke, I also plan to focus on the nature of species and natural kinds. In my opinion, those who have treated this topic have not paid sufficient attention to Leibniz’s claims that “Essence is fundamentally nothing but the possibility of the thing under consideration” and “essences are everlasting because they only concern. (shrink)

The aim of this article is to detail some reservations against the beliefs, claims, or presuppositions that current essentialist natural kind concepts (including homeostatic property cluster kinds) model grouping practices in the life sciences accurately and generally. Such concepts fit reasoning into particular preconceived epistemic and semantic patterns. The ability of these patterns to fit scientific practice is often argued in support of homeostatic property cluster accounts, yet there are reasons to think that in the life sciences kind (...) concepts exhibit a diversity of grouping practices that are flattened out by conceptualizing them as natural kinds. Instead this article argues that the process of understanding grouping practices needs to start from a more neutral position independent of any ontological account. Following Love (Acta Biotheor 57:51–75, 2009) this paper suggests that typical natural kind concepts should be broached in the first place as grouping strategies that use a variety of semantic and epistemic tactics to apply group-bound information to tasks of explanation and understanding. (shrink)

ABSTRACT I propose a division of the literature on natural kinds into metaphysical worries, semantic worries, and methodological worries. I argue that the latter set of worries, which concern how classification influences scientific practices, should occupy centre stage in philosophy of science discussions about natural kinds. I apply this methodological framework to the problems of classifying chemical species and nanomaterials. I show that classification in nanoscience differs from classification in chemistry because the latter relies heavily on (...) compositional identity, whereas the former must consider additional properties, namely, size, shape, and surface chemistry. I use this difference to argue for a scale-dependent theory of scientific classification. _1_ Introduction _2_ The Methodological Problem of Kinds _3_ Chemical Kindhood: Reactivity, Microstructure, and the Structure–Property Paradigm _4_ Scale-Dependence and Nanoscale Kinds _5_ Conclusion. (shrink)

In this paper I criticize arguments by Pauline Phemister and Matthew Stuart that John Locke's position in his An Essay Concerning Human Understanding allows for natural kinds based on similarities among real essences. On my reading of Locke, not only are similarities among real essences irrelevant to species, but natural kind theories based on them are unintelligible.

In the life sciences, biologists and philosophers lack a unifying concept of species—one that will reconcile intuitive demarcations of taxa with the fluidity of phenotypes found in nature. One such attempt at solving this “species problem” is known as Homeostatic Property Cluster theory (HPC), which suggests that species are not defined by singular essences, but by clusters of properties that a species tends to possess. I contend that the arbitrary nature of HPC’s kind criteria would permit a biological brand of (...) functionalism to inform species boundaries, thereby validating synthetic organisms as members of a species that do not belong. (shrink)

In the life sciences, biologists and philosophers lack a unifying concept of species—one that will reconcile intuitive demarcations of taxa with the fluidity of phenotypes found in nature. One such attempt at solving this “species problem” is known as Homeostatic Property Cluster theory, which suggests that species are not defined by singular essences, but by clusters of properties that a species tends to possess. I contend that the arbitrary nature of HPC’s kind criteria would permit a biological brand of functionalism (...) to inform species boundaries, thereby validating synthetic organisms as members of a species that do not belong. (shrink)

We have reason to think that a fundamental goal of natural science, on Aristotle’s view, is to discover the essence-specifying definitions of natural kinds—with biological species as perhaps the most obvious case. However, we have in the end precious little evidence regarding what an Aristotelian definition of the form of a natural kind would look like, and so Aristotle’s view remains especially obscure precisely where it seems to be most applicable. I argue that if we can (...) get a better understanding of how the forms of natural kinds are or come to be known, and how they make things intelligible, we can get a better appreciation of the nature of form in general, as well as solve certain puzzles about form and definition. (shrink)

In this paper I criticize the interpretations of John Locke on natural kinds offered by Matthew Stuart and Pauline Phemister who argue that Locke’s Essay Concerning Human Understanding allows for natural kinds based on similar real essences. By contrast, I argue for a conventionalist reading of Locke by reinterpreting his account of the status of real essences within the Essay and arguing that Locke denies that the new science of mechanism can justify the claim that similarities (...) in corpuscular structure imply similarities in sensible qualities. I argue further that Locke rejects as meaningless any talk of kinds that appeals to similarities among real essences. On my reading of Locke, similarities in real essences are not only irrelevant to species, but natural kind theories based on themare unintelligible. (shrink)

Natural Kinds and Conceptual Change is a refreshingly direct book that challenges a range of orthodox views in the philosophy of science (especially biology), the philosophy of language, and metaphysics. Amongst these are the views that species are individuals rather than natural kinds; that scientists discover the essences of natural kinds; that the causal theory of reference has commonly-ascribed implications for realism and analyticity; that there is an unacceptable form of incommensurability entailed by descriptivism (...) about reference; and that there are good grounds, familiar since Quine, for thinking that there is no distinction of significance to be drawn between changes in meaning and changes in theory. LaPorte argues against all of these claims, and if you are curious about just how he does it, then this is a book for you. (shrink)

Mineral species are, at first glance, an excellent candidate for an ideal set of natural kinds somewhere beyond the periodic table. Mineralogists have a detailed set of rules and formal procedure for ratifying new species, and minerals are a less messy subject matter than biological species, psychological disorders, or even chemicals more broadly—all areas of taxonomy where the status of species as natural kinds has been disputed. After explaining how philosophers have tended to get mineralogy wrong (...) in discussions of natural kinds, I show how minerals species don’t behave like natural kinds. They are defined on the basis of human intentionality, not merely natural distinctions. They aren’t ideal grounds for inductive inference. And they don’t form a system that divides nature along a set of equivalent joints. While this is a regrettable outcome to those of us who like the idea of science relying on natural kinds, I contend that mineralogy is doing just fine without a natural kind-based taxonomy, and may in fact be better off without one. (shrink)

‘Water is H2O’ is one of the most frequently cited sentences in analytic philosophy, thanks to the seminal work of Saul Kripke and Hilary Putnam in the 1970s on the semantics of natural kind terms. Both of these philosophers owe an intellectual debt to the empiricist metaphysics of John Locke's Essay Concerning Human Understanding, while disagreeing profoundly with Locke about the reality of natural kinds. Locke employs an intriguing example involving water to support his view that (...) class='Hi'>kinds (or ‘species’), such as water and gold, are the workmanship of the human mind. This is the point of his story about a winter visitor to England from Jamaica, who is astonished to find that the water in his basin has turned solid overnight, and proceeds to call it ‘hardened water’. Locke criticizes this judgement, maintaining that it is more consonant with common sense to regard water and ice as different kinds of substance. Putnam, by implication, disagrees. Deploying his imaginary example of Twin Earth—a distant planet where a watery-looking substance, XYZ, rather than H2O, fills the oceans and rivers—he maintains that common sense supports the judgement that XYZ and H2O, despite their superficial similarity, are not the same kind of substance, precisely because their molecular compositions are different. Here it will be argued that both views are mistaken, but that, in this dispute, Locke has more right on his side than his modern opponents do. (shrink)

Essentialism is widely regarded as a mistaken view of biological kinds, such as species. After recounting why (sections 2-3), we provide a brief survey of the chief responses to the “death of essentialism” in the philosophy of biology (section 4). We then develop one of these responses, the claim that biological kinds are homeostatic property clusters (sections 5-6) illustrating this view with several novel examples (section 7). Although this view was first expressed 20 years ago, and has received (...) recent discussion and critique, it remains underdeveloped and is often misrepresented by its critics (section 8). (shrink)

Species in biology are traditionally perceived as kinds of organisms about which explanatory and predictive generalizations can be made, and biologists commonly use species in this manner. This perception of species is, however, in stark contrast with the currently accepted view that species are not kinds or classes at all, but individuals. In this paper I investigate the conditions under which the two views of species might be held simultaneously. Specifically, I ask whether upon acceptance of an ontology (...) of species as diachronic segments of the tree of life species can perform the epistemic role of kinds of organisms to which explanatory and predictive generalizations apply. I show that, for species-level segments of the tree of life, several requirements have to be met before the performance of this epistemic role is possible, and I argue that these requirements can be met by defining species according to the Composite Species Concept proposed by Kornet and McAllister in the 1990s. (shrink)

The “species-as-individuals” thesis takes species, or taxa, to be individuals. On grounds of spatiotemporal boundedness, any biological entity at any level of complexity subject to evolutionary processes is an individual. From evolutionary theory flows an ontology that does not countenance universal properties shared by evolving entities. If austere nominalism were applied to evolving entities, however, nature would be reduced to a mere flow of passing events, each one a blob in space–time and hence of passing interest only. Yet if there (...) is genuine biodiversity in nature, if nature is genuinely carved into species, and taxa, then these evolutionary entities will be genuinely differentiated into specific kinds, each species being one of its kind. Given the fact that evolving entities have un-sharp boundaries, an appropriately weak, “non-essentialist” concept of natural kind has to be invoked that does not allow for strong identity conditions. The thesis of this paper is that species are not either individuals, or natural kinds. Instead, species are complex wholes (particulars, individuals) that instantiate a specific natural kind. (shrink)