In this paper, I will argue that Locke is a substance dualist in the general sense, in that he holds that there are, independent of our classificatory schema, two distinct kinds of substances: wholly material ones and wholly immaterial ones. On Locke’s view, the difference between the two lies in whether they are solid or not, thereby differentiating him from Descartes. My way of establishing Locke as a general substance dualist is to be as minimally committal as possible at the (...) outset, especially with respect to the classic debates on Locke’s positions in this domain, including those concerning substrata, real essences, and the like. Nonetheless, I show that minimal commitments about Locke’s primary/secondary quality distinction are sufficient to derive some substantive conclusions about his positions on these issues, as well as that he is a general substance dualist. (shrink)

Ruth Boeker offers a new perspective on Locke’s account of persons and personal identity by considering it within the context of his broader philosophical project and the philosophical debates of his day. Her interpretation emphasizes the importance of the moral and religious dimensions of his view. By taking seriously Locke’s general approach to questions of identity, Boeker shows that we should consider his account of personhood separately from his account of personal identity over time. On this basis, she argues that (...) Locke endorses a moral account of personhood, according to which persons are subjects of accountability, and that his particular thinking about moral accountability explains why he regards sameness of consciousness as necessary for personal identity over time. In contrast to some Neo-Lockean views about personal identity, Boeker argues that Locke’s account of personal identity is not psychological per se, but rather his underlying moral, religious, metaphysical, and epistemic background beliefs are relevant for understanding why he argues for a consciousness-based account of personal identity. Taking his underlying background beliefs into consideration not only sheds light on why many of his early critics do not adopt Locke’s view, but also shows why his view cannot be as easily dismissed as some of his critics assume. -/- . (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.

Locke's claims about the "inadequacy" of substance-ideas can only be understood once it is recognized that the "sort" represented by such an idea is not wholly determined by the idea's descriptive content. The key to his compromise between classificatory conventionalism and essentialism is his injunction to "perfect" the abstract ideas that serve as "nominal essences." This injunction promotes the pursuit of collections of perceptible qualities that approach ever closer to singling out things that possess some shared explanatory-level constitution. It is (...) in view of this norm regulating natural-historical inquiry that a substance-idea represents a sort for which some such constitution serves as the "real essence," i.e. as that on which all the sort's characteristic "properties" depend. (shrink)

In a well-known paper, Reginald Jackson expresses a sentiment not uncommon among readers of Locke: “Among the merits of Locke’s Essay…not even the friendliest critic would number consistency.”2 This unflattering opinion of Locke is reiterated by Maurice Mandelbaum: “Under no circumstances can [Locke] be counted among the clearest and most consistent of philosophers.”3 The now familiar story is that there are innumerable inconsistencies and internal problems contained in Locke’s Essay. In fact, it is probably safe to say that there is (...) not another canonical, well-respected, and seminal philosopher whose work is so widely thought to be swarming with inconsistencies. I, however, do not think that the common, unflattering view of Locke is accurate as a general view of the Essay. But despite my wishes to the contrary, I do believe that Locke’s chapter ‘Of Identity and Diversity’ (2.27)4 leads to (at least) one intractable problem, a problem that is the subject of this paper. (shrink)

My aim in this chapter is to survey some of the most important developments in thinking about essence in the early modern period, highlighting ways in which thinkers in the period gradually depart from the medieval Aristotelian tradition. In this tradition, essence is thought of as selective, explanatory, and kind-determining. Whereas in the beginning of the early modern period some figures (such as René Descartes, Thomas Hobbes, Margaret Cavendish, and Anne Conway) still adhere to this traditional view, later figures (including (...) Benedict de Spinoza, G.W. Leibniz, and John Locke) reject it. (shrink)

While the tradition of Locke scholarship holds that both Locke and Boyle are species anti-realists, there is evidence that this interpretation is false. Specifically, there has been some recent work on Boyle showing that he is, unlike Locke, a species realist. In this paper I argue that once we see Boyle as a realist about natural species, it is plausible to read some of Locke’s most formidable anti-realist arguments as directed specifically at Boyle’s account of natural species. This is a (...) break from the tradition because no one in the literature has yet suggested that some of Locke’s arguments in Book III of the Essay include a criticism of Boyle’s doctrine of species. Moreover, identifying Boyle as Locke’s intended target illuminates some of the more vexing passages in the Essay concerning real essences. (shrink)

There has recently been a growing interest in the topic of vagueness and indeterminacy in contemporary metaphysics, with two views taking center stage. The semantic view holds that indeterminacy is due to vagueness in the extension of concepts, while the ontological view holds that indeterminacy is due to the vagueness of certain objects. There has, however, been little research on discussions of vagueness and indeterminacy in early-modern philosophy despite the relevance of vagueness and indeterminacy for issues such as real and (...) nominal definitions, clear and distinct ideas, and the principle of complete determination. In this paper, I survey discussions of vagueness in Locke, Leibniz, and Kant and point to ways in which the problem of vagueness and indeterminacy touches on broader issues in their respective philosophies. Although Locke, Leibniz, and Kant all suggest that vagueness is a semantic phenomenon, Kant also appears to countenance an ontological view according to which objects as appearances may sometimes be indeterminate. (shrink)

Ideas play at least two roles in Locke's theory of the understanding. They are constituents of ‘propositions,’ and some of them ‘represent’ the qualities and sorts of surrounding bodies. I argue that each role involves a distinct kind of intentional directedness. The same idea will in general be an ‘idea of’ two different objects, in different senses of the expression. Identifying Locke's scheme of twofold ‘ofness’ reveals a common structure to his accounts of simple ideas and complex ideas of substances. (...) A consequence is a distinction among substance sorts parallel to one of his distinctions between primary and secondary qualities. (shrink)

Locke claimed that God superadded various powers to matter, including motion, the perfections of peach trees and elephants, gravity, and that he could superadd thought. Various interpreters have discussed the question whether Locke's claims about superaddition are in tension with his commitment to mechanistic explanation. This literature assumes that for Locke mechanistic explanation involves deducibility. We argue that this is an inaccurate interpretation and that mechanistic explanation involves a different type of intelligibility for Locke.

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.