The notion of 'natural kinds' has been central to contemporary discussions of metaphysics and philosophy of science. Although explicitly articulated by nineteenth-century philosophers like Mill, Whewell and Venn, it has a much older history dating back to Plato and Aristotle. In recent years, essentialism has been the dominant account of natural kinds among philosophers, but the essentialist view has encountered resistance, especially among naturalist metaphysicians and philosophers of science. Informed by detailed examination of classification in the natural (...) and social sciences, this book argues against essentialism and for a naturalist account of natural kinds. By looking at case studies drawn from diverse scientific disciplines, from fluid mechanics to virology and polymer science to psychiatry, the author argues that natural kinds are nodes in causal networks. On the basis of this account, he maintains that there can be natural kinds in the social sciences as well as the natural sciences. (shrink)

Our knowledge of natural categories includes beliefs not only about what is true of them but also about what would be true if the categories had properties other than (or in addition to) their actual ones. Evidence about these beliefs comes from three lines of research: experiments on category-based induction, on hypothetical transformations of category members, and on definitions of kind terms. The 1st part of this article examines results and theories arising from each of these research (...) streams. The 2nd part considers possible unified theories for this domain, including theories based on ideals and norms. It also contrasts 2 broad frameworks for modal category information: one focusing on beliefs about intrinsic or essential properties, the other focusing on interacting causal relations. (shrink)

How do-or how should-we parse the world into kinds of things? Going back at least to Plato, most philosophers have done so with respect to some notion or other of natural kinds. And many analyses of natural kinds have been essentialistic-that is defining those kinds with respect to universals, or some set of intrinsic properties, or necessary and sufficient conditions. And there's a long-standing dispute between thinkers who regard scientific categories as natural kinds with essential properties (...) fixed by nature-those that "cut nature at its joints"-and thinkers who maintain that our classifications and categories have no essence and instead merely reflect human interests and values. A typical example of the former would be "having a mass of 1.7 × 10-27," and examples of the latter would be the categories of "ADHD," "race," or "child abuse." Khalidi aims for an epistemic, naturalistic, non-essentialist, account of natural kinds, one which comfortably embraces not only the usual candidates favored by essentialists (e.g., elementary particles, chemical elements, biological species), but also categories in the social and behavioral sciences. Drawing on cases from many scientific fields, from fluid mechanics and polymer science to virology and psychiatry, Khalidi argues that "natural kinds are investigative or epistemic kinds, in the sense that they are the categories revealed by our systematic attempts to gain knowledge of nature" (p. 43). Moreover, he claims that natural kinds can be "fuzzy" (i.e. have indefinite boundaries), satisfy epistemic virtues to varying degrees, and be mind-dependent in a way that doesn't detract from their reality or objectivity. Although the book is pitched for a sophisticated and philosophically informed audience (and, needless to say, too complex to be adequately summarized in a brief notice such as this), it's clearly written, nuanced, compellingly argued, and worth the effort for JSE readers curious about the unavoidable metaphysical dimensions of doing science of any kind. (shrink)

The present study examined the effects of semantic structure on simple inductive judgments about category members. For a particular category, subjects were told that one of the species had a given property and were asked to estimate the proportion of instances in the other species that possessed the property. The results indicated that category structure—in particular, the typicality of the species—influenced subjects' judgments. These results were interpreted by models based on the following assumption: When little is known about the underlying (...) distribution of a property, subjects assume that the distribution mirrors that of better-known properties. For this reason, if subjects learn that an unknown property is possessed by a typical species, they are more likely to generalize than if the same fact had been learned about an atypical species. (shrink)

The base rate fallacy is directly dependent on a particular judgment paradigm in which information may be unambiguously designated as either “base rate” or “individuating,” and in which subjects make two-stage sequential judgments. The paradigm may be a poor match for real world settings, and the fallacy may thus be undefined for natural ecologies of judgment.

The notion of 'natural kinds' has been central to contemporary discussions of metaphysics and philosophy of science. In recent years, essentialism has been the dominant account of natural kinds among philosophers, but the essentialist view has encountered resistance. Informed by detailed examination of classification in the natural and social sciences, Prof. Muhammad Ali Khalidi argues against essentialism and for a naturalist account of natural kinds. By looking at case studies drawn from diverse scientific disciplines, from fluid (...) mechanics to virology and polymer science to psychiatry, the author argues that natural kinds are nodes in causal networks. On the basis of this account, he maintains that there can be natural kinds in the social sciences as well as the natural sciences. (shrink)

The target article raises important questions about the applicability of experimental social psychology research on topics with policy implications. This commentary focuses on the importance of attending to a variety of factors to improve ecological validity as well as considering the ultimate factors shaping behavior and the role of natural categories in the stability of stereotypes and their influence.

Following the recent recognition that humans are an active force in nature that gave rise to a new geological epoch, this article explores the implications of the shift to the Anthropocene for social theory. The argument assumes that the emerging conditions compel an expansion and deepening of the timescale of the social-theoretical perspective and that such an enhancement has serious repercussions for the concept of human agency. First, the Anthropocene is conceptualized as a nascent cognitively structured cultural model rather than (...) simply a geological epoch. Second, the vast and deep timescale, in the light of which the new time unit and its generative agency alone make sense, is analysed along with the human world's objective, sociocultural and subjective axes. Finally, the elements of the concept of agency are recomposed in their temporal and relational contexts. At the reflexive level throughout, the need for social theory to develop a cognitive-theoretical approach in conjunction with a weak naturalistic ontology is suggested. (shrink)

The more one reads about the topic of natural kinds, the more one is reminded of that famous scene in The Hitchhiker’s Guide to the Galaxy in which Deep Thought—after a mere 7.5 million years of doing calculations—reveals that the answer to the Ultimate Question of Life, the Universe and Everything was 42. Faced with bewildered reactions from the eager audience, Deep Thought explains: “I think the problem, to be quite honest with you, is that you’ve never actually known (...) what the question is” .In the case of the growing literature on natural kinds, it is easy to get a feeling that something similar is going on. While philosophers keep advancing novel accounts of natural kinds, at the same time there is considerable disagreement about what exactly the problem is that such accounts should solve. To some, natural kinds are real kinds in nature that exist in the world independently of human interests and practices. At the very least, they are human-made kinds that correspon .. (shrink)

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)

If we want to assess whether or not a naturalized phenomenology is a desideratum or a category mistake, we need to be clear on precisely what notion of phenomenology and what notion of naturalization we have in mind. In the article I distinguish various notions, and after criticizing one type of naturalized phenomenology, I sketch two alternative takes on what a naturalized phenomenology might amount to and propose that our appraisal of the desirability of such naturalization should be more positive, (...) if we opt for one or both of the latter alternatives. (shrink)

This major new study by one of the most penetrating and persistent critics of philosophical and scientific orthodoxy, returns to Aristotle in order to examine the salient categories in terms of which we think about ourselves and our nature, and the distinctive forms of explanation we invoke to render ourselves intelligible to ourselves. The culmination of 40 years of thought on the philosophy of mind and the nature of the mankind Written by one of the world’s leading philosophers, the (...) co-author of the monumental 4 volume _Analytical Commentary on the Philosophical Investigations_ Uses broad categories, such as substance, causation, agency and power to examine how we think about ourselves and our nature Platonic and Aristotelian conceptions of human nature are sketched and contrasted Individual chapters clarify and provide an historical overview of a specific concept, then link the concept to ideas contained in other chapters. (shrink)

This major study examines the most fundamental categories in terms of which we conceive of ourselves, critically surveying the concepts of substance, causation, agency, teleology, rationality, mind, body and person, and elaborating the conceptual fields in which they are embedded. The culmination of 40 years of thought on the philosophy of mind and the nature of the mankind Written by one of the world’s leading philosophers, the co-author of the monumental 4 volume _Analytical Commentary on the Philosophical Investigations_ Uses (...) broad categories, such as substance, causation, agency and power to examine how we think about ourselves and our nature Platonic and Aristotelian conceptions of human nature are sketched and contrasted Individual chapters clarify and provide an historical overview of a specific concept, then link the concept to ideas contained in other chapters. (shrink)

This major new study by one of the most penetrating and persistent critics of philosophical and scientific orthodoxy, returns to Aristotle in order to examine the salient categories in terms of which we think about ourselves and our nature, and the distinctive forms of explanation we invoke to render ourselves intelligible to ourselves. The culmination of 40 years of thought on the philosophy of mind and the nature of the mankind Written by one of the world’s leading philosophers, the (...) co-author of the monumental 4 volume _Analytical Commentary on the Philosophical Investigations_ Uses broad categories, such as substance, causation, agency and power to examine how we think about ourselves and our nature Platonic and Aristotelian conceptions of human nature are sketched and contrasted Individual chapters clarify and provide an historical overview of a specific concept, then link the concept to ideas contained in other chapters. (shrink)

There is growing support for the view that social categories like men and women refer to “objective types” (Haslanger 2000, 2006, 2012; Alcoff 2005). An objective type is a similarity class for which the axis of similarity is an objective rather than nominal or fictional property. Such types are independently real and causally relevant, yet their unity does not derive from an essential property. Given this tandem of features, it is not surprising why empirically-minded researchers interested in fighting oppression (...) and marginalization have found this ontological category so attractive: objective types have the ontological credentials to secure the reality (and thus political representation) of social categories, and yet they do not impose exclusionary essences that also naturalize and legitimize social inequalities. This essay argues that, from the perspective of these political goals of fighting oppression and marginalization, the category of objective types is in fact a Trojan horse; it looks like a gift, but it ends up creating trouble. I argue that objective type classifications often lack empirical adequacy, and as a result they lack political adequacy. I also provide, and in reference to the normative goals described above, several arguments for preferring a social ontology of natural kinds with historical essences. (shrink)

The concept of an ontological category is central to metaphysics. Metaphysicians argue about which category of existence an object should be assigned to, whether one category can be reduced to another one, or whether there might be different equally adequate systems of categorization. Answers to these questions presuppose a clear understanding of what precisely an ontological category is, and Jan Westerhoff now provides the first in-depth analysis. After examining a variety of attempted definitions, he proceeds to argue for a new (...) understanding of ontological categories, according to which they are systematizations of our knowledge of the world rather than essential characteristics of the world itself. Metaphysicians will find his work highly stimulating. (shrink)

Cognitive developmental evidence is sometimes conscripted to support ''naturalized epistemology'' arguments to the effect that a general epistemic stance leads children to build theory-like accounts of underlying properties of kinds. A review of the evidence suggests that what prompts conceptual acquisition is not a general epistemic stance but a series of category-specific intuitive principles that constitute an evolved ''natural metaphysics''. This consists in a system of categories and category-specific inferential processes founded on definite biases in prototype formation. Evidence (...) for this system provides a better understanding of the limited ''plasticity'' of ontological commitments as well as a computationally plausible account of their initial state, avoiding ambiguities about innateness. This may provide a starting point for a ''naturalized epistemology'' that takes into account evolved properties of human conceptual structures. (shrink)

Cognitive developmental evidence is sometimes conscripted to support ''naturalized epistemology'' arguments to the effect that a general epistemic stance leads children to build theory-like accounts of underlying properties of kinds. A review of the evidence suggests that what prompts conceptual acquisition is not a general epistemic stance but a series of category-specific intuitive principles that constitute an evolved ''natural metaphysics''. This consists in a system of categories and category-specific inferential processes founded on definite biases in prototype formation. Evidence (...) for this system provides a better understanding of the limited ''plasticity'' of ontological commitments as well as a computationally plausible account of their initial state, avoiding ambiguities about innateness. This may provide a starting point for a ''naturalized epistemology'' that takes into account evolved properties of human conceptual structures. (shrink)

The concept of an ontological category is central to metaphysics. Metaphysicians argue about which category an object should be assigned to, whether one category can be reduced to another one, or whether there might be different equally adequate systems of categorization. Answers to these questions presuppose a clear understanding of what precisely an ontological category is, an issue which is rarely addressed; Jan Westerhoff presents the first in-depth analysis both of the use made of ontological categories in the metaphysical (...) literature, and of various attempts at defining them. He also develops a new theory of ontological categories which implies that there will be no unique system, and that the ontological category an object belongs to is not an essential property of that object. Systems of ontological categories are structures imposed on the world, rather than reflections of a deep metaphysical reality already present. All metaphysicians should find Westerhoff's book highly stimulating. (shrink)

E. J. Lowe, a prominent figure in contemporary metaphysics, sets out and defends his theory of what there is. His four-category ontology is a metaphysical system which recognizes four fundamental categories of beings: substantial and non-substantial particulars and substantial and non-substantial universals. Lowe argues that this system has an explanatory power which is unrivalled by more parsimonious theories and that this counts decisively in its favour. He shows that it provides a powerful explanatory framework for a unified account of (...) causation, dispositions, natural laws, natural necessity and many other related matters, thus constituting a full metaphysical foundation for natural science. (shrink)

In the second part of the Critique of Judgment, Immanuel Kant provides a transcendental analysis of the bases of our right to employ teleological conceptions in biology. A living organism exemplifies the conception of a natural end insofar as the organization of the parts to form a whole is the result of a process in which the organism is both cause and effect of itself. Kant’s analysis of the concept of a natural purpose is guided, in part, by (...) his general theory of logic. By examining the manner in which the logical modes of relation are used as a basis for analyzing the concept of a natural purpose, I hope to accomplish two goals: to compare Kant’s analysis of the category of community to the analysis of the concept of a natural purpose; to evaluate some of the strengths and weaknesses ofKant’s account of community and natural purpose; to consider one criticism of Kant’s use of the logical form of the disjunctive as a basis for the analysis of these conceptions that is developed by Charles Sanders Peirce. Peirce indicates that Darwin’s theory of biological evolution was one of the primary causes that led him revisit Kant’s logic and his analysis of the categories of relation. (shrink)

For the most part, the papers collected in this volume stern from presentations given at a conference held in Tucson over the weekend of May 31 through June 2, 1985. We wish to record our gratitude to the participants in that conference, as well as to the National Science Foundation and the University of Arizona SBS Research Institute for their financial support. The advice we received from Susan Steele on organizational matters proved invaluable and had many felicitous consequences for the (...) success of the con­ ference. We also would like to thank the staff of the Departments of Linguistics of the University of Arizona and the University of Massachusetts at Amherst for their help, as weIl as a number of individuals, including Lin Hall, Kathy Todd, and Jiazhen Hu, Sandra Fulmer, Maria Sandoval, Natsuko Tsujimura, Stuart Davis, Mark Lewis, Robin Schafer, Shi Zhang, Olivia Oehrle-Steele, and Paul Saka. Finally, we would like to express our gratitude to Martin Scrivener, our editor, for his patience and his encouragement. Vll INTRODUCTION The term 'categorial grammar' was introduced by Bar-Rillel as a handy way of grouping together some of his own earlier work and the work of the Polish logicians and philosophers Lesniewski and Ajdukiewicz, in contrast to approaches to linguistic analysis based on phrase structure grammars. (shrink)

Inductive reasoning is fundamental to human cognition, yet it remains unclear how we develop this ability and what might influence our inductive choices. We created novel categories in which crucial factors such as domain and category structure were manipulated orthogonally. We trained 403 4–9-year-old children to categorise well-matched natural kind and artefact stimuli with either featural or relational category structure, followed by induction tasks. This wide age range allowed for the first full exploration of the developmental trajectory of (...) inductive reasoning in both domains. We found a gradual transition from perceptual to categorical induction with age. This pattern was stable across domains, but interestingly, children showed a category bias one year later for relational categories. We hypothesise that the ability to use category information in inductive reasoning develops gradually, but is delayed when children need to process and apply more complex category structures. (shrink)

The notion of a natural numbers object in a monoidal category is defined and it is shown that the theory of primitive recursive functions can be developed. This is done by considering the category of cocommutative comonoids which is cartesian, and where the theory of natural numbers objects is well developed. A number of examples illustrate the usefulness of the concept.

A main function of common natures in Avicenna’s metaphysics is supposed to be providing an objective ground for the categories. Thus, it is commonly assumed that in his metaphysics things are objectively divided into the categories into which they are because members of each category share the same common nature. However, common natures cannot perform the function unless they are shared, in a real sense of the word, by the members of the respective categories, and it is (...) not clear at all in what real sense Avicenna took common natures to be shared by them. On the one hand, he rejected Platonic and Aristotelian realisms about common natures, the two standard accounts of how common natures are shared by their instances. On the other hand, it is unclear that his alternative account(s) of common natures renders them genuinely common. The primary goal of this paper is to examine whether Avicenna’s common natures can provide an objective ground for the categories. It considers various interpretations of Avicenna's account and argues that they are either incorrect interpretations of Avicenna or do not render common natures genuinely common. It concludes with proposing to look elsewhere in Avicenna’s system to find the objective ground. (shrink)

The aim of this investigation is to discuss the merits of the three radically divergent views as to the nature and function of the categories held by Kant, Ward and Alexander.

When we approach medieval writings on the natural law in terms of our contemporary interpretations of such basic categories as reason, nature, and natural order, these writings are bound to seem confused, incomplete, and unsophisticated. Yet if we allow these writings to speak in their own terms, respecting the integrity of their thought, a different picture emerges. We find there an account of the natural law which is significantly different from any contemporary version. This account is (...) illuminating precisely because it demonstrates that it is possible to think in very different ways about some fundamental issues. (shrink)

Models of category learning have been extensively studied in cognitive science and primarily tested on perceptual abstractions or artificial stimuli. In this paper, we focus on categories acquired from natural language stimuli, that is, words. We present a Bayesian model that, unlike previous work, learns both categories and their features in a single process. We model category induction as two interrelated subproblems: the acquisition of features that discriminate among categories, and the grouping of concepts into (...) class='Hi'>categories based on those features. Our model learns categories incrementally using particle filters, a sequential Monte Carlo method commonly used for approximate probabilistic inference that sequentially integrates newly observed data and can be viewed as a plausible mechanism for human learning. Experimental results show that our incremental learner obtains meaningful categories which yield a closer fit to behavioral data compared to related models while at the same time acquiring features which characterize the learned categories. (shrink)