Natural Kinds and Natural Kind Terms: Myth and Reality

Abstract

The paper 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 -microessentialism -is untenable even in a 'placeholder' version; and that the currently popular HPC theory of natural kinds is correct only to an extent which fails to vindicate the Kripke-Putnam account. This undermines the metasemantics required for antidescriptivist semantics.

Essential Properties Are Super-Explanatory: Taming Metaphysical Modality

“…Because of this, they are generally resistant to any suggestion that kinds have ‘essences’, viewing such thinking as grounded in outmoded metaphysics. (See, for example, Hull 1965; Sober 1980; Wilson, Barker, and Brigandt 2007; Häggqvist and Wikforss 2018.) We agree that natural kinds are complex, but we will show that even so they are typically unified by certain super-explanatory core properties, which are thus naturally viewed as essences .…”

“…(See e.g. Hull 1965, Sober 1980, Wilson et al 2007, Häggqvist and Wikforss 2018 We agree that natural kinds are complex, but will show that even so they are typically unified by certain super-explanatory core properties, which are thus naturally viewed as essences. While other philosophers have noted that causal mechanisms are needed to explain the unity of natural kinds (Boyd 1991, Craver 2000, Khalidi 2013, they have failed to appreciate how this role is typically played by single super-explanatory properties.…”

“…Some further complications: it is molecular structure , not chemical formula, that explains the properties of chemical compounds (isomers can be very different from each other); isotopy makes a difference to some (but not all) of the properties of elements and compounds; some chemical mixtures are Kinds in their own right. A rich literature explores the complexity of chemical and other natural Kinds (inter alia Hendry 2006; Needham 2008; Chang 2012; Khalidi 2013; Häggqvist and Wikforss 2018). We take this literature to show that there are more Kinds than you might initially suppose, often nested within each other, each with their own super-explainers for their shared properties.…”

“… 14 Many theorists who are suspicious of Kind ‘essences’ take it as definitional that they must be intrinsic properties (Hull 1965; Sober 1980; Wilson, Barker, and Brigandt 2007; Rieppel 2010; Häggqvist and Wikforss 2018). Similarly, essentialists like Mark Ellis (2011; 670) also view historical essentialism with suspicion, suggesting that historical essentialists ‘creatively revive the illusion of species essentialism’.…”

Water has a microstructural essence after all

“…Over the years a number of philosophers have attacked the K&P picture of the metaphysics of natural kinds and the corresponding semantic story by trying to show that it is naïvely oversimplified and in conflict with real science. Here we will focus on a recent paper by Häggqvist and Wikforss (hereafter: H&W) as one of the latest examples of this current (Häggqvist & Wikforss, 2017), but the thrust of their arguments is shared by others. 3 We will argue that the metaphysical picture offered by K&P is not as vulnerable as H&W contend, at least when it comes to non-living substance kinds such as water and gold.…”