This paper offers a new approach to an old debate about superaddition in Locke. Did Locke claim that some objects have powers that are unrelated to their natures or real essences? The question has split commentators. Some (Wilson, Stuart, Langton) claim the answer is yes and others (Ayers, Downing, Ott) claim the answer is no. This paper argues that both of these positions may be mistaken. I show that Locke embraced a robust epistemic humility. This epistemic humility includes ignorance of (...) the real essences of bodies, of the causal processes underlying the production of natural phenomena, and of God’s method of creation. I show how this epistemic humility offers strong support for an agnostic response to the question of superaddition. Locke did not intend to claim that bodies either do or do not have properties unrelated to their real essences. Instead, his primary goal in discussing the topic was to emphasize the strict limits to human knowledge. (shrink)

One of several important issues that inform contemporary philosophy of chemistry is the issue of structural explanation, precisely because modern chemistry is primarily concerned with microstructure. This paper argues that concern over microstructure, albeit understood differently than it is today, also informs the chemical philosophy of Robert Boyle. According to Boyle, the specific microstructure of ‘chymical atoms’, understood in geometric terms, accounts for the unique essential properties of different chemical substances. Because he considers the microstructure of ‘chymical atoms’ as semi-permanent, (...) Boyle considers these stable entities as operationally irreducible, even if they are not ontologically fundamental. While it is generally believed that our contemporary concern over structural explanation is a function of modern chemistry’s emphasis on microstructure, this discussion of structural explanation in Boyle will serve as a case study to illustrate the manner in which many of our contemporary concerns have deeply historical origins and the manner in which the history of chemistry can substantively inform issues in contemporary philosophy of chemistry. (shrink)

This paper studies Robert Boyle's account of kinds and classification. A number of commentators have argued that, for Boyle, classifications are inevitably the product of conventions. Others have challenged this reading, arguing that, according to Boyle, the corpuscular makeup of bodies gives rise to hard-edged natural kinds and classes. We argue that Boyle's position is more complicated than the available realist and conventionalist readings acknowledge. We argue that, according to Boyle, the individuation of kinds was to some degree the result (...) of convention. At the same time, however, Boyle held that our classificatory practices are subject to constraints. We identify some of these constraints by turning to Boyle's discussion of the late scholastic debate about the plurality of forms, in particular the contributions of Jacopo Zabarella and Daniel Sennert. In this way, we clarify how Boyle strikes a balance between realist and conventionalist elements in his treatment of kinds. (shrink)

In this paper I criticize arguments by Pauline Phemister and Matthew Stuart that John Locke's position in his An Essay Concerning Human Understanding allows for natural kinds based on similarities among real essences. On my reading of Locke, not only are similarities among real essences irrelevant to species, but natural kind theories based on them are unintelligible.

In this paper I criticize the interpretations of John Locke on natural kinds offered by Matthew Stuart and Pauline Phemister who argue that Locke’s Essay Concerning Human Understanding allows for natural kinds based on similar real essences. By contrast, I argue for a conventionalist reading of Locke by reinterpreting his account of the status of real essences within the Essay and arguing that Locke denies that the new science of mechanism can justify the claim that similarities in corpuscular structure imply (...) similarities in sensible qualities. I argue further that Locke rejects as meaningless any talk of kinds that appeals to similarities among real essences. On my reading of Locke, similarities in real essences are not only irrelevant to species, but natural kind theories based on themare unintelligible. (shrink)

I examine the views of Thomas Reid with respect to a certain version of the problem of induction: Why are inductions using natural kinds successful, and what justifies them? I argue that while both Reid holds a kind of conventionalist view about natural kinds, this conventionalism has a realistic component which allows him to answer both questions.

In this encyclopedia entry I canvass the current interpretations of John Locke's concept of Real Essence and the role it plays in his philosophy.