Saul Kripke in his revolutionary and influential series of lectures from the early 1970s (later published as the book Naming and Necessity) famously resurrected John Stuart Mill's theory of proper names. Kripke at the same time rejected Mill's theory of general terms. According to Kripke, many natural kind terms do not fit Mill's account of general terms and are closer to proper names. Unfortunately, Kripke and his followers ignored key passages in Mill's A System of Logic in which Mill enunciates (...) a sophisticated and detailed theory of natural kind terms that anticipates and is in some ways superior to Kripke's. (shrink)

In this paper I sketch William Whewell’s attempts to impose order on classificatory mineralogy, which was in Whewell’s day (1794e1866) a confused science of uncertain prospects. Whewell argued that progress was impeded by the crude reductionist assumption that all macroproperties of crystals could be straightforwardly explained by reference to the crystals’ chemical constituents. By comparison with biological classification, Whewell proposed methodological reforms that he claimed would lead to a natural classification of minerals, which in turn would support advances in causal (...) understanding of the properties of minerals. Whewell’s comparison to successful biological classification is particularly striking given that classificatory biologists did not share an understanding of the causal structure underlying the natural classification of life (the common descent with modification of all organisms). Whewell’s key proposed methodological reform is consideration of multiple, distinct principles of classification. The most powerful evidence in support of a natural classificatory claim is the consilience of claims arrived at through distinct lines of reasoning, rooted in distinct conceptual approaches to the target objects. Mineralogists must consider not only elemental composition and chemical affinities, but also symmetry and polarity. Geometrical properties are central to what makes an individual mineral the type of mineral that it is. In Whewell’s view, function and organization jointly define life, and so are the keys to understanding what makes an organism the type of organism that it is. I explain the relationship between Whewell’s teleological account of life and his natural theology. I conclude with brief comments about the importance of Whewell’s classificatory theory for the further development of his philosophy of science and in particular his account of consilience. (shrink)

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

When we ask what natural kinds are, there are two different things we might have in mind. The first, which I’ll call the taxonomy question, is what distinguishes a category which is a natural kind from an arbitrary class. The second, which I’ll call the ontology question, is what manner of stuff there is that realizes the category. Many philosophers have systematically conflated the two questions. The confusion is exhibited both by essentialists and by philosophers who pose their accounts in (...) terms of similarity. It also leads to misreading philosophers who do make the distinction. Distinguishing the questions allows for a more subtle understanding of both natural kinds and their underlying metaphysics. (shrink)

Several recent interpretations see Hegel's theory of the Concept as a form of conceptual realism, according to which finite reality is articulated by objectively existing concepts. More precisely, this theory has been interpreted as a version of natural kind essentialism, and it has been proposed that its function is to account for the possibility of genuine explanations. This suggests a promising way to reconstruct the argument that Hegel's theory of objective concepts is based on—an argument that shows that the possibility (...) of explanation rests on metaphysical preconditions and that natural kind essentialism gives the only adequate account of those preconditions. But in order for such a reconstruction to be successful, one needs to spell out the metaphysical features in virtue of which Hegelian natural kinds can account for the possibility of explanation. The article takes up this challenge. It offers the first detailed analysis of the modal fine-structure of Hegel's natural kind essentialism and shows how Hegel's position, thus understood, provides the details needed to complete the explanation-based argument. (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)

Although some authors hold that natural kinds are necessarily relative to disciplinary domains, many authors presume that natural kinds must be absolute, categorical features of the reality —often assuming that without even mentioning the alternative. Recognizing both possibilities, one may ask whether the difference especially matters. I argue that it does. Looking at recent arguments about natural kind realism, I argue that we can best make sense of the realism question by thinking of natural kindness as a relation that holds (...) between a category and a domain. (shrink)

The accepted narrative treats John Stuart Mill's Kinds as the historical prototype for our natural kinds, but Mill actually employs two separate notions: Kinds and natural groups. Considering these, along with the accounts of Mill's 19th-century interlocutors, forces us to recognize two distinct questions. First, what marks a natural kind as worthy of inclusion in taxonomy? Second, what exists in the world that makes a category meet that criterion? Mill's two notions offer separate answers to the two questions: natural groups (...) for taxonomy, and Kinds for ontology. This distinction is ignored in many contemporary debates about natural kinds and is obscured by the standard narrative which treats our natural kinds just as a development of Mill's Kinds. (shrink)