Some philosophers understand natural kinds to be the categories which are constraints on enquiry. In order to elaborate the metaphysics appropriate to such an account, I consider the complicated history of scurvy, citrus, and vitamin C. It may be tempting to understand these categories in a shallow way (as mere property clusters) or in a deep way (as fundamental properties). Neither approach is adequate, and the case instead calls for middle-range ontology: starting from categories which we identify in the world (...) and elaborating their structure, but not pretending to jump ahead to a complete story about fundamental being. (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)

The label realist in the debate about natural kinds can imply different things. Many authors in this debate subscribe to views that are in some way realist, but without making clear whether the realism in question specifically attaches to kind categories or something else. The traditional understanding of realism about natural kinds is stated in terms of the mind-independence criterion. However, a recent tendency in the debate is to reject this understanding on the ground of its incompatibility with naturalistic approaches (...) to natural kinds. The aim of this paper is to disentangle different meanings attached to the term realism about natural kinds and examine arguments for rejecting the traditional mind-independence framing of the debate. I recommend the reestablishment of mind-independent realism as a legitimate contender for naturalist approaches to natural kinds by indicating that mind-independent realists have at their disposal all the resources to subscribe to such an approach. I proceed by showing how keeping the traditional distinction between realist and antirealist views in terms of mind-independence allows us to keep track of important distinctions between different accounts of natural kinds which are otherwise blurred. Then I examine the arguments against this traditional framing and conclude that they either (1) rest on a conflation between mind-independence of kinds versus entities belonging to kinds, or (2) unjustifiably presuppose that mind-independent realists do not have resources to uphold a naturalistic view of natural kinds. (shrink)

Beauvoir’s The Second Sex stands out as a master class in the accommodation of conceptual and inferential practices to real, objective gender kinds. Or so I will argue. To establish this framing, we will first need in hand the kind of scientific epistemology that correctly reconciles epistemic progress and error, particularly as pertains to the unruly social sciences. An important goal of the paper is to develop that epistemological framework and unlock its ontological implications for the domain of gender. As (...) we will see, the real gender kinds that contemporary social scientists successfully identify and track are very much the same kinds to which Beauvoir was coordinating reference in The Second Sex. The correct identification of those kinds endures as a moral and political priority, regardless of one’s other gender-related normative agenda. (shrink)

The kinds of real or natural kinds that support explanation and prediction in the social sciences are difficult to identify and track because they change through time, intersect with one another, and they do not always exhibit their properties when one encounters them. As a result, conceptual practices directed at these kinds will often refer in ways that are partial, equivocal, or redundant. To improve this epistemic situation, it is important to employ open-ended classificatory concepts, to understand when different research (...) programs are tracking the same real kind, and to maintain an ongoing commitment to interact causally with real kinds to focus reference on those kinds. A tempting view of these non-idealized epistemic conditions should be avoided: that they signal an ontological structure of the social world so plentiful that it would permit ameliorated classificatory schemes to achieve their normative aims regardless of whether they defer to real-kind classificatory schemes. To ground these discussions, the essay appeals to an overlooked convergence in the systematic naturalistic frameworks of Richard Boyd and Ruth Millikan. (shrink)

Scientists represent their world, grouping and organizing phenomena into classes by means of concepts. Philosophers of science have historically been interested in the nature of these concepts, the criteria that inform their application and the nature of the kinds that the concepts individuate. They also have sought to understand whether and how different systems of classification are related and more recently, how investigative practices shape conceptual development and change. Our aim in this paper is to provide a critical overview of (...) some of the key developments in this philosophical literature and identify some interesting issues it raises about the prospects of the so-called “special sciences”, including psychiatry, psychology, and the mind-brain sciences more generally, to discover natural kinds. (shrink)

This afterword to Species and Beyond provides some reflections on species, with special attention to what I think the most significant developments have been in the thinking of biologists and philosophers working on species over the past 25 years, as well as some bad jokes.