Some scientific categories seem to correspond to genuine features of the world and are indispensable for successful science in some domain; in short, they are natural kinds. This book gives a general account of what it is to be a natural kind and puts the account to work illuminating numerous specific examples.

Thomas S. Kuhn's classic book is now available with a new index.

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 lieu of an abstract, here is a brief excerpt of the content:Philosophy, Psychiatry, & Psychology 9.3 (2002) 219-227 [Access article in PDF] The Practical Kinds Model as a Pragmatist Theory of Classification Peter Zachar Pragmatist theories of scientific classification are intended to be pluralistic models that recognize different ways of cutting up the world as valuable, but do not require us to adopt whatever-goes relativism or metaphysical antirealism. How ironic that my application of pragmatism to psychopathology has been charged (...) with not being sufficiently pluralistic because it tries to fit all psychiatric disorders into the Procrustean bed of practical kinds. The Practical Kinds Model in General As a point of clarification, the practical kinds model is not a description of a type of category combined with an argument that all psychiatric disorders should be seen as belonging to that type. If it were that kind of model, I would fully agree with Haslam that practical kinds, fuzzy kinds, and discrete kinds are all potential types of psychiatric disorders. Like Nick Haslam, I believe that there are many different things in the DSM-IV and the ICD-10, and they cannot neatly be classified as the same type of thing.Rather than identifying a type of category, the practical kinds model is a general theory of scientific classification. It is a nonessentialistic theory. Essentialism is the view that things have real essences. In the Aristotelian version of essentialism, an essence is an internal structure, and it is the internal structure that makes anything be the kind of thing it really is. In this classical category model, category members either have the essence or they do not, and everything that has the appropriate essence is a member of that category. The world is supposed to therefore have a well-defined structure, and the job of the scientist is to discover that structure. Ian Hacking (1999) has termed this view of categorization inherent structurism.The practical kinds model does not deny that things have internal structures; it only denies that internal structure by itself determines category membership. Internal structure is an important consideration in identifying categories, but external criteria can always play a role. External or relational criteria play more important roles in some cases than they do in others, but they cannot be eliminated once and for all. Essentialistic theories, which favor an almost exclusive focus on inherent structures, have the advantage of being more parsimonious, but they do so by ignoring real complexity.The best way to illustrate this point is to examine a category whose identification is heavily weighted in terms of internal criteria, or an inherent structure, such as a chemical element. [End Page 219] For example, hydrogen is defined as the element that has an atomic number of 1. This means that it has one proton in its nucleus and normally one electron orbiting its nucleus. The atomic number reflects an internal property, and anything that has an atomic number of 1 is hydrogen. The same is true for the other elements. Anything that has an atomic number of 79 is gold; anything that has an atomic number of 19 is potassium, and so on. Also part of the essentialistic view is the notion that all the important properties of an element are systematically (or lawfully) related to its internal structure.It would be foolish to deny the practical utility of the atomic theory of chemistry. But even in this strongest of cases, external criteria can potentially play a role in how we decide to carve up the world and what we identify as the relevant categories. The point can be clearly illustrated with a Gedanken experiment based on the ideas of Donnellan (1983). Assume that we were to make contact with extraterrestrial life, and the result of that contact was our initiation into a larger galactic community like those portrayed on Star Trek or Babylon 5. Fortunately for us, it turns out that all planets in the community use a gold-based currency, just like we do on Earth. What we call gold, however, is too common to be the galactic basis of a currency, but a particular isotope... (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)

Richard Boyd’s Homeostatic Property Cluster Theory is becoming the received view of natural kinds in the philosophy of science. However, a problem with HPC Theory is that it neglects many kinds highlighted by scientific classifications while at the same time endorsing kinds rejected by science. In other words, there is a mismatch between HPC kinds and the kinds of science. An adequate account of natural kinds should accurately track the classifications of successful science. We offer an alternative account of natural (...) kinds that better recognizes the diversity of epistemic aims scientists have for constructing classifications. That account introduces the idea of a classificatory program and provides criteria for judging whether a classificatory program identifies natural kinds. (shrink)

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 kinds from being natural kinds. Furthermore, the defeasibility requirement captures (...) the idea that natural kind classifications are tools for investigating the empirical world. (shrink)

With this manifesto, John Dupré systematically attacks the ideal of scientific unity by showing how its underlying assumptions are at odds with the central conclusions of science itself.

The diagnosis of psychopathic personality disorder has salience for forensic clinical practice. It influences decisions regarding risk, treatability and sentencing, indeed, in certain jurisdictions it serves as an aggravating factor that increases the likelihood of a capital sentence. The concatenation of symptom that is associated with modern conceptions of the disorder can be discerned in early writings, including the book of Psalms. Despite its forensic clinical importance and historical pedigree the concept remains elusive and controverted. In this paper I describe (...) an attempt to map the concept of psychopathic personality disorder—the Comprehensive Assessment of Psychopathic Personality (CAPP). I outline the processes used to create the concept map; I summarise evidence in support of the content validity of the map and describe different operations designed to operationalise the construct. It is only when conceptual clarity is achieved that valid operations and measures can be created. I end with a plea for more carefully considered application of statistical methods; applications that better fit the theoretical questions being posed. (shrink)

Psychopathy attracts considerable interdisciplinary interest. The idea of a group of people with abnormal morality and interpersonal relations raises important philosophical, legal, and clinical issues. However, before engaging these issues, we ought to examine whether this category is scientifically grounded. We frame the issue in terms of the question whether ‘psychopathy’ designates a natural kind according to the cluster approaches. We argue that currently there is no sufficient evidence for an affirmative answer to this question. Furthermore, we examine three ways (...) of dealing with the category of psychopathy. We could eliminate the category, revise it, or subscribe to a more encompassing account of kinds, which could capture psychopathy as it is currently conceptualized. We argue that while a revision of the category of psychopathy is to be expected with empirical and theoretical advancements, we also emphasize its role in clinical and forensic research that makes it an important pragmatic kind. (shrink)

Psychopaths continue to be demonised by the media and estimates suggest that a disturbing percentage of the population has psychopathic tendencies. This timely and controversial new book summarises what we already know about psychopathy and antisocial behavior and puts forward a new case for its cause - with far-reaching implications. Presents the scientific facts of psychopathy and antisocial behavior. Addresses key questions, such as: What is psychopathy? Are there psychopaths amongst us? What is wrong with psychopaths? Is psychopathy due to (...) nature or nurture? And can we treat psychopaths? Reveals the authors' ground-breaking research into whether an underlying abnormality in brain development leaves psychopaths with an inability to feel emotion or fear. The resulting theory could lead to early diagnosis and revolutionize the way society, the media and the state both views and contends with the psychopaths in our midst. (shrink)

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)

Classifying Madness (Springer, 2005) concerns philosophical problems with the Diagnostic and Statistical Manual of Mental Disorders, more commonly known as the D.S.M. The D.S.M. is published by the American Psychiatric Association and aims to list and describe all mental disorders. The first half of Classifying Madness asks whether the project of constructing a classification of mental disorders that reflects natural distinctions makes sense. Chapters examine the nature of mental illness, and also consider whether mental disorders fall into natural kinds. The (...) second half of the book addresses epistemic worries. Even supposing a natural classification system to be possible in principle, there may be reasons to be suspicious of the categories included in the D.S.M. I examine the extent to which the D.S.M. depends on psychiatric theory, and look at how it has been shaped by social and financial factors. I aim to be critical of the D.S.M. without being antagonistic towards it. Ultimately, however, I am forced to conclude that although the D.S.M. is of immense practical importance, it is unlikely to come to reflect the natural structure of mental disorders. (shrink)

Especially troublesome in this dispute is the status of the natural sciences, and this is where Hacking finds some of his most telling cases, from the conflict ...

Effective and specifically targeted social and therapeutic responses for antisocial personality disorders and psychopathy are scarce. Some authors maintain that this scarcity should be overcome by revising current syndrome - based classifications of these conditions and devising better biocognitive classifications of antisocial individuals. The inspiration for the latter classifications has been embedded in the Research domain criteria approach (RDoC). RDoC - type approaches to psychiatric research aim at transforming diagnosis, provide valid measures of disorders, aid clinical practice, and improve health (...) outcomes by integrating the data on the genetic, neural, cognitive, and affective systems underlying psychiatric conditions. In the first part of the paper, we discuss the benefits of such approaches in comparison to the dominant syndrome-based ones and review recent attempts at building biocognitive classifications of antisocial individuals. Other researchers, how ever, have objected that biocognitive approaches in psychiatry are committed to an untenable form of explanatory. (shrink)

The Hare Psychopathy Checklist (PCL; Hare, Neumann, & Mokros 2018) scales are among the most widely used forensic assessment tools. Their perceived utility rests partly on their ability to assess stable personality traits indicative of a lack of conscience, which then facilitates behavioral predictions useful in forensic decisions. In this systematic review, we evaluate the empirical evidence behind 3 fundamental justifications for using the PCL scales in forensics, namely, that they are empirically predictive of (1) criminal behavior, (2) treatment outcomes, (...) and (3) a lack of conscience. We found the PCL scales can predict criminal behavior to a statistically significant degree, though with important limitations. We found no evidence of PCL psychopathy being predictive of treatment and rehabilitation outcomes. We found no evidence of PCL psychopathy being predictive of a lack of conscience. These findings disprove widespread beliefs about PCL psychopathy among forensic practitioners and questions the current and future role of the PCL scales in forensic settings. (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)

The paper considers whether psychiatric kinds can be natural kinds and concludes that they can. This depends, however, on a particular conception of ‘natural kind’. We briefly describe and reject two standard accounts – what we call the ‘stipulative account’ (according to which apparently a priori criteria, such as the possession of intrinsic essences, are laid down for natural kindhood) and the ‘Kripkean account’ (according to which the natural kinds are just those kinds that obey Kripkean semantics). We then rehearse (...) a more permissive account: Richard Boyd’s ‘homeostatic property cluster’ (HPC) account. We argue that psychiatric kinds can in principle count as natural kinds on the HPC account. Moreover, specific psychiatric kinds (Tourette’s, schizophrenia, etc.) can be natural kinds even if the category psychiatric disorder is not itself a natural kind. (shrink)

Taxometric analyses were applied to the construct of psychopathy (as measured by the Psychopathy Checklist) and to several variables reflecting antisocial childhood, adult criminality, and criminal recidivism. Subjects were 653 serious offenders assessed or treated in a maximum-security institution. Results supported the existence of a taxon underlying psychopathy. Childhood problem behaviors provided convergent evidence for the existence of the taxon. Adult criminal history variables were continuously distributed and were insufficient in themselves to detect the taxon.