It is common to defend the Homeostatic Property Cluster ( HPC ) view as a third way between conventionalism and essentialism about natural kinds ( Boyd , 1989, 1991, 1997, 1999; Griffiths , 1997, 1999; Keil , 2003; Kornblith , 1993; Wilson , 1999, 2005; Wilson , Barker , & Brigandt , forthcoming ). According to the HPC view, property clusters are not merely conventionally clustered together; the co-occurrence of properties in the cluster is sustained by a similarity generating ( (...) or homeostatic ) mechanism . I argue that conventional elements are involved partly but ineliminably in deciding which mechanisms define kinds , for deciding when two mechanisms are mechanisms of the same type, and for deciding where one particular mechanism ends and another begins. This intrusion of conventional perspective into the idea of a mechanism raises doubts as to whether the HPC view is sufficiently free of conventional elements to serve as an objective arbiter in scientific disputes about what the kinds of the special sciences should be. (shrink)

The article defends the doctrine that Linnaean taxa, including species, have essences that are, at least partly, underlying intrinsic, mostly genetic, properties. The consensus among philosophers of biology is that such essentialism is deeply wrong, indeed incompatible with Darwinism. I argue that biological generalizations about the morphology, physiology, and behavior of species require structural explanations that must advert to these essential properties. The objection that, according to current “species concepts,” species are relational is rejected. These concepts are primarily concerned with (...) what it is for a kind to be a species and throw little light on the essentialist issue of what it is for an organism to be a member of a particular kind. Finally, the article argues that this essentialism can accommodate features of Darwinism associated with variation and change. (shrink)

Ernst Mayr has argued that Darwinian theory discredited essentialist modes of thought and replaced them with what he has called "population thinking". In this paper, I characterize essentialism as embodying a certain conception of how variation in nature is to be explained, and show how this conception was undermined by evolutionary theory. The Darwinian doctrine of evolutionary gradualism makes it impossible to say exactly where one species ends and another begins; such line-drawing problems are often taken to be the decisive (...) reason for thinking that essentialism is untenable. However, according to the view of essentialism I suggest, this familiar objection is not fatal to essentialism. It is rather the essentialist's use of what I call the natural state model for explaining variation which clashes with evolutionary theory. This model implemented the essentialist's requirement that properties of populations be defined in terms of properties of member organisms. Requiring such constituent definitions is reductionistic in spirit; additionally, evolutionary theory shows that such definitions are not available, and, moreover, that they are not needed to legitimize population-level concepts. Population thinking involves the thesis that population concepts may be legitimized by showing their connections with each other, even when they are not reducible to concepts applying at lower levels of organization. In the paper, I develop these points by describing Aristotle's ideas on the origins of biological variation; they are a classic formulation of the natural state model. I also describe how the development of statistical ideas in the 19th century involved an abandoning of the natural state model. (shrink)

In this article I assess the problems and prospects of a microstructural approach to chemical substances. Saul Kripke and Hilary Putnam famously claimed that to be gold is to have atomic number 79 and to be water is to be H2O. I relate the first claim to the concept of element in the history of chemistry, arguing that the reference of element names is determined by atomic number. Compounds are more difficult: water is so complex and heterogeneous at the molecular (...) level that `water is H2O' seems false under some interpretations. I sketch a response to this problem. (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)

I discuss several problems for Williamson’s counterfactual-theory of modal knowledge and argue that they have a common source, in that the theory neglects to elucidate the proper constraints on modal reasoning. Williamson puts forward an empirical hypothesis that rests on the role of counterfactual reasoning for modal knowledge. But he overlooks central questions of normative modal epistemology. In order for counterfactual reasoning to yield correct beliefs about modality, it needs to be suitably constrained. I argue that what is needed is, (...) specifically, information concerning the nature or essence of things. By integrating this information, essentialist deduction arguably provides a better account of our knowledge of modality. Furthermore, I argue that essences have distinctive causal and explanatory powers—indeed, essences are superexplanatory for how things are. Compared to Williamson’s counterfactual-theory, superexplanatory essentialism clarifies what the proper constraints on modal reasoning are, and why they have such a special status. (shrink)

There are three theories in the epistemology of modality that have received sustained attention over the past 20 years: conceivability-theory, counterfactual-theory, and deduction-theory. In this paper we argue that all three face what we call the problem of modal epistemic friction. One consequence of the problem is that for any of the three accounts to yield modal knowledge, the account must provide an epistemology of essence. We discuss an attempt to fend off the problem within the context of the internalism (...) versus externalism debate about epistemic justification. We then investigate the effects that the PMEF has on reductive and non-reductive theories of the relation between essence and modality. (shrink)

I propose that we approach the epistemology of modality by putting modal metaphysics first and, specifically, by investigating the metaphysics of essence. Following a prominent Neo-Aristotelian view, I hold that metaphysical necessity depends on the nature of things, namely their essences. I further clarify that essences are core properties having distinctive superexplanatory powers. In the case of natural kinds, which is my focus in the paper, superexplanatoriness is due to the fact that the essence of a kind is what causes (...) all the many properties and behaviors that are typically shared by all the instances of the kind. Accordingly, we know what is necessarily true of kinds by knowing what is essential to them in the sense of actually playing such causal-explanatory roles. Modal reasoning aimed at discovering metaphysical necessity thus proceeds via essentialist deduction: we move from essentialist truths to reach necessary truths. (shrink)

Is there anything that members of each binary category of gender have in common? Even many non-essentialists find the lack of unity within a gender worrying as it undermines the basis for a common political agenda for women. One promising proposal for achieving unity is by means of a shared historical lineage of cultural reproduction with past binary models of gender. I demonstrate how such an account is likely to take on board different binary and also non-binary systems of gender. (...) This implies that all individuals construed as members of the category, “women” are in fact not members of the same historical kind after all! I then consider different possible means of modifying the account but conclude negatively: the problem runs deeper than has been appreciated thus far. (shrink)

Recent metaphysics has turned its focus to two notions that are—as well as having a common Aristotelian pedigree—widely thought to be intimately related: grounding and essence. Yet how, exactly, the two are related remains opaque. We develop a unified and uniform account of grounding and essence, one which understands them both in terms of a generalized notion of identity examined in recent work by Fabrice Correia, Cian Dorr, Agustín Rayo, and others. We argue that the account comports with antecedently plausible (...) principles governing grounding, essence, and identity taken individually, and illuminates how the three interact. We also argue that the account compares favorably to an alternative unification of grounding and essence recently proposed by Kit Fine. (shrink)

The article examines the role of natural kinds in semantic theorizing, which has largely been conducted in isolation from relevant work in science, metaphysics, and philosophy of science. We argue that the Kripke–Putnam account of natural kind terms, despite recent claims to the contrary, depends on a certain metaphysics of natural kinds; that the metaphysics usually assumed—micro-essentialism—is untenable even in a ‘placeholder’ version; and that the currently popular homeostatic property cluster theory of natural kinds is correct only to an extent (...) that fails to vindicate the Kripke–Putnam account. This undermines the metasemantics required for anti-descriptivist semantics. _1_ Introduction _2_ From Semantics to Metaphysics _3_ Metaphysics, Part I: The Demise of Micro-essentialism _3.1_ Original micro-essentialism _3.2_ Placeholder essentialism _4_ Metaphysics, Part II: Homeostatic Property Cluster Theory _5_ Prospects for Natural Kind Term Semantics. (shrink)

This paper is an investigation of the general logic of "identifications", claims such as 'To be a vixen is to be a female fox', 'To be human is to be a rational animal', and 'To be just is to help one's friends and harm one's enemies', many of which are of great importance to philosophers. I advocate understanding such claims as expressing higher-order identity, and discuss a variety of different general laws which they might be thought to obey. [New version: (...) Nov. 4th, 2016]. (shrink)

Suppose that two geysers, about one mile apart, erupt at irregular intervals, but usually erupt almost exactly at the same time. One would suspect that they come from a common source, or at least that there is a common cause of their eruptions. And this common cause surely acts before both eruptions take place. This idea, that simultaneous correlated events must have prior common causes, was first made precise by Hans Reichenbach (Reichenbach 1956). It can be used to infer the (...) existence of unobserved and unobservable events, and to infer causal relations from statistical relations. Unfortunately it does not appear to be universally valid, nor is there agreement as to the circumstances in which it is valid. (shrink)

There are no "special sciences" in Fodor's sense. There is a large group of sciences, "historical sciences," that differ fundamentally from the physical sciences because they quantify over a different kind of natural or real kind, nor are the generalizations supported by these kinds exceptionless. Heterogeneity, however, is not characteristic of these kinds. That there could be an univocal empirical science that ranged over multiple realizations of a functional property is quite problematic. If psychological predicates name multiply realized functionalist properties, (...) then there is no single science dealing with these: human psychology, ape psychology, Martian psychology and robot psychology are necessarily different sciences. (shrink)

Editors' introduction to the special issue on homology (Biology and Philosophy Vol. 22, Issue 5, 2007).

The architects of the modern synthesis banned essentialism from evolutionary theory. This rejection of essentialism was motivated by Darwin’s theory of natural selection, and the continuity of evolutionary transformation. Contemporary evolutionary biology witnesses a renaissance of essentialism in three contexts: “origin essentialism” with respect to species and supraspecific taxa, the bar coding of species on the basis of discontinuities of DNA variation between populations, and the search for laws of evolutionary developmental biology. Such “new essentialism” in contemporary biology must be (...) of a new kind that accommodates relational (extrinsic) properties as historical essences and cluster concepts of natural kinds. (shrink)

Alan Sidelle's Necessity, Essence, and Individuation is a sustained defense of empiricism—or, more generally, conventionalism—against recent attacks by realists. Sidelle focuses his attention on necessity a posteriori, a kind of necessity which contemporary realists have taken to support realism over empiricism. Turning the tables against the realists, Sidelle argues that if there are in fact truths necessary a posteriori, it is not realism, but rather empiricism which provides the best explanation for them.

Two inter-linked theses are defended in this paper. One is the Duhemian theme that a rigid distinction between physical and chemical properties cannot be upheld. Duhem maintained this view not because the latter are reducible to the former, but because if physics is to remain consistent with chemistry it must prove possible to expand it to accommodate new features, and a rigid distinction would be a barrier to this process. The second theme is that naturally occurring isotopic variants of water (...) are in fact distinct substances, and naturally occurring samples of water are mixtures of these substances. For most practical purposes it is convenient to treat protium oxide, deuterium oxide, and so on, as the same chemical substance, but to insist on this as a matter of principle would stand in conflict with the first thesis. (shrink)

The paper defends the doctrine that Linnaean taxa, including species, have essences that are, at least partly, underlying intrinsic, mostly genetic, properties. The consensus among philosophers of biology is that such essentialism is deeply wrong, indeed incompatible with Darwinism. I argue that biological generalizations about the morphology, physiology, and behavior of species require structural explanations that must advert to these essential properties. The paper concludes by summarizing my responses to the objection that, according to current “species concepts,” species are relational, (...) and to the objection that essentialism cannot accommodate features of Darwinism associated with variation and change. (shrink)