Locke's Ideas of Mind and Body by Han-Kyul Kim (review)

In the brief space I have, I can provide only a quick taste of what the reader is in for with Han-Kyul Kim's Locke's Ideas of Mind and Body. Kim argues that his account of Locke's metaphysics of substance in terms of ideas of mind and body (nominal essences) makes sense of the relation between four crucial and often overlooked topics in Locke's philosophy: "(1) Locke's mind-body nominalism, (2) his epistemic humility, (3) his functionalist account of substrata, and (4) his naturalist approach to the human mind" (4). Kim opens in chapter 1 with a survey of various ontological doctrines (materialism, substance dualism, and property dualism) that have been associated with Locke and provides arguments that none are correct. Instead, Kim puts forward a novel argument that Locke's metaphysics of substance should be understood in functional terms. Qualities are explained and known, insofar as we know them, in terms of their causal/functional roles: any intrinsic natures should be understood simply as possibly multi-realizable bearers of those causal roles.

This dovetails with Kim's understanding of Locke's "substance nominalism" (chapter 2), the view that the distinction between the mental and the material (mind and body) is only a nominal (ideational) one reflecting our two different perspectives on the world given in sensation and reflection. So, "the two nominal entities [mind and body] are differentiated only by reference to their functional roles in our psychological and physical theories," both of which should be understood in a naturalistic framework (131). Consistent also with Locke's "epistemic humility," the subject of chapter 3, any claim about the fundamental stuff of the universe—that it is either material, immaterial, or something with both material and immaterial properties—confuses "ideas with reality" (9).

Shedding light on this confusion between ideas and reality allows Kim to see in Locke a kind of naturalism consistent with an "emergentist" interpretation of superaddition (chapter 4): everything from motion to thinking emerges as something more than the material particles so organized and "made fit" by God for that emergence. Higher-level beings "may thus appear to be entirely distinct from and over and above the solid particles of which they are composed, but are nevertheless described as 'superadded' only in the sense that they are not contained in the idea of matter" (89). Such confusion between what belongs to the realm of ideas and what belongs to reality also leads to the perennial "mind-body problem" for which a solution is offered in chapter 5. Following Colin McGinn, Consciousness and Its Objects (Clarendon Press, 2004), Kim argues that once we realize that all Lockean talk about material or immaterial substance is really only about our ideas (nominal essences) and that it takes a being far superior to us to organize the fundamental stuff in such a way that it exhibits the causal order it does, part of which results in the nominal essences (ideas) of matter and thinking, we should realize that mind-body interaction as problematic is due simply to the way we think about the mind and the body. A superior understanding of the natural world would reveal some property, in terms of its functional role, that would "enable us to see a priori how the phenomena we call 'mental' and 'physical' are related to each other" (112).

In crafting his functionalist and "substance nominalist" interpretation of Locke, Kim has provided interesting links to various historical (William Carroll, Richard Burthogge) and contemporary (Colin McGinn) "Spinozist" readings of Locke as well as a historical naturalist reading (Joseph Priestley) that have not been in the foreground for some time. He also appeals to twentieth- and twenty-first-century metaphysics of the mind (Frank Ramsey, Jaegwon Kim, Donald Davidson, Colin McGinn) to shed more light on various arguments. Some may object to doing the history of philosophy by appeal to contemporary thinking. I think Kim has done a good job of allowing Locke...