Locke bases his model of an autonomous mind on a dialectical interchange between models and theories, cabinets and minds, collections and concepts.10 “Man’s power,” as Locke sums up, and his “ways of operation, [are] much the same in the material and intellectual world.”11 Locke’s name therefore has come to stand for a concept of mind that would emerge as one of the chief legacies of Enlightenment empiricism, despite the fact that a return to his own habits tends to paint a much more complicated picture.12 Undoubtedly, Locke’s argument and its legacy helped introduce a warpage into mainstream ways of viewing the world. This is the system of the understanding as an observer among its objects, the mind consisting of, on the one hand, a set of faculties like reason and judgment, and, on the other, the ideal objects with which it works. And it establishes this through a complex web of metaphors, each of which leans on the memory of haptic practice. But our readings of Locke in general expect us to perform a more complicated transformative trick: at once to remember what it feels like to stock a cabinet with its objects, and to accept an etiology of reason which, in the end, will insist that it has no place for feeling. Take, for instance, Paul de Man’s influential reading of the Essay. “When Locke,” de Man convincingly argues, “develops his own theory of words and language, what he constructs turns out to be in fact a theory of tropes.”13 This seems exactly right. Locke’s curatorial mind is not only modeled on the labors of a collector in his cabinet; it also works, fundamentally, by modeling ideas on patterns observed in the stuff of experience, de Man’s “theory of tropes.”14 “Of course,” de Man continues, “he would be the last man in the world to realize and to acknowledge this. One has to read him, to some extent, against or regardless of his own explicit statements.” We are asked, therefore, to accept Locke as a foundational figure in the modern mobilization of metaphor, while we are encouraged to overlook the (metaphorical) rudiments on which his most conceptual metaphors are built. We are encouraged to treat him as a theorist of pure reason, when all his remarks remind us of thinking as a practice. Even while Locke reminds us of the embeddedness of thought in the stuff of the senses, we are asked to forget.
The usual treatment of the history of the empiricist project, de Man’s remarks notwithstanding, is to note its general hostility to metaphor, especially when metaphor is imagined as a mere rhetorical choice among others.15 In this sense, metaphor is the stuff of poetry and stagecraft, what, in the conventional formulation offered by Thomas Tyers, “takes the hearer and reader by storm,” convincing “our passions … before our reason, which is too often made a dupe of.”16 But increasingly, recent work has drawn our attention to the ways in which thinkers were sensitive to metaphor as an important tool for organizing systems of ideas.17 This insight is in fact developed by Locke, though he avoids the word “metaphor” itself. “It may,” he remarks,
lead us a little towards the original of all our notions and knowledge, if we remark how great a dependence our words have on common sensible ideas; and how those which are made us of to stand for actions and notions quite removed from sense, have their rise from thence, and from obvious sensible ideas are transferred to more abstruse significations, and made to stand for ideas that come not under the cognizance of our senses; v.g. to imagine, apprehend, comprehend, adhere, conceive, instill, disgust, disturbance, tranquility, &c. are all words taken from the operations of sensible things, and applied to certain modes of thinking.18
The double consciousness of Locke’s treatment of metaphor is on full display here. On the one hand, Locke goes out of his way in this passage to avoid even the hint of a rhetorical flourish—while, on the other hand, he expects us continually to hear the origins of words as figures for sensible simples. It is not merely that sensible ideas are made twice “to stand,” or that ideas “rise” from the senses; these are of course things less proper to ideas than to the person having them, but this is merely the beginning of the ways in which ideas are, Locke insists, traceable to haptic or somatic dimensions of experience. Rather, he suspects that his whole vocabulary, and the conceptual field in which he thinks, might “depend” upon, that is, “hang from,” ideas first produced by the senses. “Apprehend” means “grasp,” “adhere” means “stick to”; “instill” means “put in by drops”; “disgust” means “averse taste”; and so on. And precisely here is the moment I mentioned before—where language more appropriate to Paradise Lost turns up in the Essay: “Spirit,” Locke continues, means “breath”; “angel” means “messenger.” Words penned in Locke’s cabinet would not be out of place in Milton’s bed.
Philosophical analysis in this account therefore begins to look like metaphor analysis, as metaphor emerges as the basic generative condition of intellectual life in the first place.19 While Locke has gone out of his way to avoid the word, what he is describing is the work of metaphor embedded in the intellect. Indeed, he offers us a definition without the proper name, going so far as to hide “metaphor” in its Latin equivalent, for what is “transfer” (“carry across”) but the Latin word for “metaphor,” Aristotle’s Greek word for the same sort of ferrying or “carrying across” of meaning from one realm to another?20 And what is an angel doing here, except as a figure for the carrying of messages from one ineffable realm to another?
As Locke imagines it, the conceptual metaphor—the mind as cabinet—governs the coordination of source and target domains across a range of subordinate metaphors, including the ways in which reason does its workmanlike labor, the lodging of ideas like books in the memory, the ways in which the mind is furnished, the paperiness of its inscription surfaces, and so on.21 In this sense, metaphor does not merely describe a linguistic flourish.22 It captures a special category of brainwork. So when the recent cognitive turn in philosophy argues that conceptual work appropriates neural networks developed in bodily activity, that conceptual thought is overlaid on sensorimotor networks of neurons,23 it pursues Locke’s suggestion to trace the “originals of all our notions and knowledge” to their roots in the senses. It is not just that something else is carried across from the source domain of the metaphor to the target domain, or even that those domains are thoroughly blended; it is that the neural networks for the literal and metaphorical senses of a word seem to be partly shared.24 Metaphor, in this line of thought, emerges as the special, possibly unique condition in which the mind can hold two ideas superimposed at once. Metaphor causes sensory experience to overlap with conceptual relationships. It nevertheless, to a greater or lesser degree, appears to be the basic condition of language and knowledge acquisition, especially when that knowledge turns to thinking about the conditions of knowledge.25 As Mark Johnson puts it, “In a very strong sense, philosophy is metaphor.”26
One of Locke’s examples—“apprehend”—has recently received a great deal of attention in the laboratory, for the metaphor itself directly and dramatically relates embodiment to mentation.27 The word understood in its conceptual sense, something like “hold something in the mind,” clearly leans on a bodily engagement with the world, the reaching out and grasping of something.