Locke's Idea of Spatial Extension

Notes and Discussions LOCKE'S IDEA OF SPATIAL EXTENSION Ia Book II, chapter ii, section 1 of the Essay, Locke, ~;uggesting that a distinction ought to be observed between simple and complex ideas, says that a simple idea is "uncompounded, [and] contains in it nothing but one uni]orm appearance or conception in the mind, and is not distinguishable into different ideas." Yet thirteen chapters later he admits that "though . . . [space is] justly reckoned amongst our simple ideas, yet none of the distinct ideas we have of . . . [it] is without all manner of composition: it is the very nature of... [it] to consist of parts." I It is an obvious objection that these two passages haxdly square with each other. The earliest instance of it is, perhaps, that which, according to Locke's friend and editor Pierre Coste, "M. Barbeyrac, ~, present professeur en droit ~t Groningue .... me communiqua.., dam une Lettre que je fis voir 6 M. Locke," and to which Locke replied "peu tie jours apr~s." Thus it is objected to Mr. Locke that, if space consists of parts, as it is confessed.., he should not have reckoned it in the number of simple ideas: because it seems to be inconsistent with what he says elsewhere, that a simple idea is uncompounded and contains in it nothing but one uni]orm appearance, or conception o/ [sic] the mind, and is not distinguishable into di~erent ideas.... It is further objected that Mr. Locke has not given in the Second Chapter of the Second Book, where he begins to speak of simple ideas, an exact definition of what he understands by the word simple ideas.2 James Gibson in one of the standard works on the Essay was later to make the same two criticisms, explicitly attributing Locke's difficulties over space to an i John Locke, An Essay Concerning Human Understanding, ed. with intro. John W. Yolton, 5th ed. (1706), 2 vols. (London, 1961), I.I, xv, 9. Unlike words in square brackets, italicized words are in general not mine. Coste reports this in a footnote to his second (1729) and revised French edition of the Essay. (A. C. Fraser [2 vols., Oxford, 1894] reproduces in French most of this footnote in one of his own at H, xv, 9.) The substance of Coste's footnote---the criticism and "la r&ponse que M. Locke me dicta"--makes up a footnote (from which I take my English quotations) in the fifth English edition of the Essay, the additions to which were wholly Locke's responsibility. This Barbeyrac-Coste-Locke interchange took place between 1702 and 1703. In a letter to Locke dated 15 June 1702, Jean de Barbeyrac mentions his having asked Coste to communicate to Locke some difficulties he has had about simple ideas. In one dated 6 January 1703, he expresses his satisfaction with Locke's reported reply. I am grateful to Dr. W. yon Leyden for knowledge of these Lovelace Collection letters (Bodl. MS Locke, c. 3 fol. 140). [313] 314 HISTORY OF PHILOSOPHY inadequate definition of "simple idea." s And, more recently s~ll, Professor R. I. Aaron has also pointed out that the passages conflict.4 It is true that Locke is often neither clear nor informative about criteria for the simplicity of an idea. I suggest, however, that the present inconsistency arises not from his tmclarity as to what is to count as a simple idea, but from unclarity as to what is to count as an idea. As has been argued by others elsewhere,s Locke uses the term "idea" to refer at least to both concepts and mental images, and it seems to me that the difficulty he faces concerning the idea of space is merely apparent in that it is due solely to this equivocation. When Locke offers reasons for supposing that the idea of space is "not without all manner of composition ," he is thinking, I want to suggest, of ideas as images, whereas when he offers reasons as to why it is "justly reckoned amongst our simple ideas," he is thinking of them as concepts.. Despite making an explicit distinction between the ideas of "space," "extension , and "expansion" (II...