Locke on Semantic and Epistemic Role of Simple Ideas of Sensation

LOCKE ON THE SEMANTIC AND EPISTEMIC

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LOCKE ON THE SEMANTIC AND EPISTEMIC ROLE OF SIMPLE IDEAS OF SENSATION by MARTHA BRANDT BOLTON Abstract: This paper argues that Locke has a representative theory of sensitive knowledge. Perceivers are immediately aware of nothing but sensory ideas in the mind; yet perceivers think of real external substances that correspond to and cause those ideas, and they are warranted in believing that those substances exist (at that time). The theory poses two questions: what warrants the truth of such beliefs? What is it in virtue of which sensory ideas represent external objects and how do they make perceivers think of those objects? Both the epistemic and semantic issues need to be addressed. This paper urges that Locke’s basic account of warrant is roughly reliabilist. The causal origin of sensory ideas assures that, in general, sense based beliefs are true. Locke defines the limit of this warrant by the theoretical point that we cannot discuss skeptical doubt without assuming the truthfulness of our perceptual faculty. Turning to the semantic question, the paper argues that ideas are mental modifications or entities. They are not intrinsically representative (satisfiable), but rather represent only by virtue of their causal origin. They merely “track” the presence of substances and their qualities. Ideas nevertheless prompt perceivers to think of their causes. This is roughly because sensory ideas have a specific mental role, namely, to serve as marks for distinguishing substances and their respective qualities for purposes of action. The paper suggests that, for Locke, the challenge posed by the semantic veil of ideas is to explain this externally directed marking function within bounds of his anti-innatism. But it concludes that his answers to the twin questions fit together reasonably well.

Pacific Philosophical Quarterly 85 (2004) 301 –321 © 2004 University of Southern California and Blackwell Publishing Ltd. Published by Blackwell Publishing Ltd, 9600 Garsington Road, Oxford OX4 2DQ, UK and 350 Main Street, Malden, MA 02148, USA.

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1. According to the veil-of-perception charge, Locke’s theory of ideas erects a cognitive barrier between our minds and material sensible things around us. If ideas are mental entities and objects of perception, then there is no way to prove that things other than our ideas exist. Worse, there may be no way to explain how we manage to think of, direct thought to, things other than our ideas, assuming they exist. There are two aspects of the problematic veil of perception, one that might be called “semantic”, having to do with representation, and the other epistemic.1 Just as Locke’s account of the representative role of sensory ideas invites a specific skeptical challenge, which he may not meet, so his claims about sensory knowledge make demands on his account of sensory content, which he may not satisfy. Those who fault Locke’s handling of skepticism tend to conclude that his representationalism is untenable. By the same token, unless his theory of representation is viable, his doctrine of sensitive knowledge collapses. It cannot get off the ground unless perceptual acts and beliefs have intentional content consisting of real beings without us. What is Locke’s theory of how perception is directed externally? Sensory ideas are internal contents of immediate awareness; what do they contribute to cognition of external things? The question I want to consider is whether sensory ideas penetrate the semantic veil they may seem to set up. In recent secondary literature, there has been a good deal of debate about the ontological status of Locke’s sensory ideas. Some accounts of the status of ideas relate closely to the matter I want to investigate, that is: how Locke supposes sensory ideas contribute to perceptual states that are of, directed toward, external objects and their qualities. Since these accounts are prominent, I begin by orienting them in relation to the issue of perceptual states and their external objects. John Yolton has long urged that Locke’s theory of ideas is in the service of a direct realism.2 His use of ‘idea’ is ambiguous between perceptual acts and perceptual objects: a person’s sensory idea of a particular horse, say, is either a perceptual act directed toward a horse, or, on the second meaning, the horse in relation to the person’s sensory awareness. Taking “idea” in the second sense, the idea is the horse as it appears to the perceiver. The horse (perceptual object) is just as it is perceived to be, yet at the same time, outside the mind – ontologically independent of the perceiver.3 Perhaps the best textual evidence that this is what Locke meant by “real being without us” is his habit of saying that sensory ideas are “in” things, such as horses, in the sense that qualities are in them. But this is an inaccurate expression, he confesses. He wants us to understand that ideas are effects in us; qualities are powers of real things to cause sensory ideas; and the ideas are of the qualities.4 Accordingly Vere Chappell urges © 2004 University of Southern California and Blackwell Publishing Ltd.

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a view on which ideas are dependent on mental acts or states.5 Locke’s ideas, on this view, are the immediately accessible contents of our various states of awareness. An idea is an intentional entity, just as a mind takes it to be, but ontologically dependent on a mental act. A person who is perceiving a real horse and a person who is hallucinating a horse both have an (occurrent) sensory idea of horse, on this view. So far, this account of the ontological status of ideas does not explain how the idea of horse directs attention to a real horse. In fact, Chappell suggests Locke has no clear account of the “representative function” of ideas in relation to external things.6 Michael Ayers holds a third view of ideas (Ayers, 1986; Ayers, 1991, pp. 60–6). He agrees that Locke sometimes treats ideas as perceptual acts and sometimes as intentional entities, but urges that simple ideas of sensation have a different status in context of Locke’s causal theory of perception. Sensory ideas are raw, “non-intentional” sensations; that is, they are neither intentional entities (as, e.g., a feeling of cold feet might be) nor contents of immediate awareness that intrinsically point beyond themselves. They are just “blank effects” caused in us by things without, signs that stand in thought for their causes. It is clear why simple ideas have external intentional content, on this view. What may not be clear is how we become aware of what ideas stand for – objects taken to be real, or external. It is worth mentioning that each of these views on the ontological status of ideas has consequences for Locke’s resemblance thesis: ideas of primary qualities do, whereas ideas of secondary qualities do not, resemble the qualities of bodies that cause those ideas. If sensory ideas are intentional entities, as Yolton and Chappell maintain, we can easily understand what Locke means by saying that primary qualities – extension, solidity, figure, motion, and so on – are “the same” in ideas and in things: the idea of a motion is an intentional motion and it resembles (is the same as) the motion of a body in roughly the way a horse’s gallop in a movie resembles the movement of a horse (Chappell, 1994, pp. 30, 35). On the other hand, if ideas are non-intentional sensations, as Ayers maintains, then Locke’s thesis unfortunately suggests that ideas (sensations) are moving, extended, and so on (Ayers, 1991, pp. 62– 3). But although the ontological status of ideas is clearly an important question, it is not in the fore in this paper. My concern is the close relation between Locke’s epistemic doctrine and his theory of sensory representation. Because he defends a realist account of sensitive knowledge, he is committed to explaining how sensory ideas put us in perceptual contact with the real world. What role do ideas have engendering conscious states directed to the particular things with which we have causal encounters?7 I begin by considering the theory of sensitive knowledge, which requires that perceptual states with external intentional content should, in some way, be brought about by simple ideas of sense. Then I take up the question whether Locke has an account © 2004 University of Southern California and Blackwell Publishing Ltd.

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of the representative function of sensory ideas adequate to support his epistemic theory.

2. Many critics of Locke charge that he has no effective response to the form of skepticism to which his theory of sensitive knowledge is susceptible. According to Locke, sensitive knowledge is a species of knowledge less certain than intuition and demonstration. The more certain types of knowledge are evidenced by “agreement” and “disagreement” internal to ideas (which seem here to be intentional entities). Sensitive knowledge does not have as high a degree of certainty: but “going beyond bare probability”, it “deserves the name of knowledge”. In particular, when we receive sensory ideas, we can be certain of the existence of particular objects that caused those ideas and have powers to cause ideas of the same sorts. (Essay IV.xi.1,2,3,9,14). Regarding the certainty (i.e. warrantedness) of such beliefs, a form of skepticism is entertained. Surely it cannot be doubted that we have sensory ideas, but “. . . whether we can thence certainly inferr the existence of anything without us, which corresponds to that Idea, is that, whereof some Men think there may be a question made . . .” (Essay IV.ii.14; also IV.xi.8). In fact, we have ideas in the absence of corresponding objects in memory, non-experiential thought, and dreams; skeptics ask whether “all might be a dream”. In response, Locke does not deny that the skeptical speculation makes sense, but he offers no further evidence against it. Its falsity cannot be demonstrated, he grants (Essay IV.xi.10). But it is pragmatically flawed: to ask the question is pointless if it occurs in a dream; the reality of perceptual objects is never doubted in practice; we need no greater certainty than we have (Essay IV.ii.14; IV.xi.3,8). Pragmatic responses are not logical refutations. They will not satisfy those who want to rebut skepticism by demonstrating that we do, or at least can, have knowledge about sensible things because such things are ontologically dependent on our cognitive states or abilities. The veil of perception charge against Locke originated from philosophers, back at least to Berkeley, who repudiated realism to refute skepticism. But even those who do not advocate irrealism about the external world suggest Locke’s response is none too effective.8 Yet his pragmatic strategy does, at least, rest on a sound theoretical point: if the general truth-conduciveness of our cognitive faculties is placed in doubt, it destroys our ability to give evidence either way. We cannot remove the doubt (nor ratify it) without assuming the truthfulness of those same faculties. The certainty we have of the “testimony of our senses” is “. . . the greatest assurance we are capable of, concerning the Existence of material Beings. For we cannot . . . talk of © 2004 University of Southern California and Blackwell Publishing Ltd.

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Knowledge it self, but by the help of those Faculties, . . .”. (Essay IV.xi.3). This is not a platitude, but a philosophical truth. Non-circular debate about the reliability of the senses is impossible9 and Locke is content with this impasse. In part, this is due to the project of the Essay, which stands in the Aristotelian tradition of attempts to explain how, and why, our cognitive processes manage, by and large, to get things right.10 Matters up for investigation include what those faculties are, their components and modes of operation, as well as the best way to use them to make progress in the sciences. That our faculties, operating properly in their natural setting, produce true beliefs is taken for granted. But it is not that Locke is uninterested in skeptical doubt. Far from ignoring it, he uses the skeptical stand-off to define the warrant he ascribes to sensitive knowledge. It is a warrant conferred by the unavoidable presumption that our natural sensory faculty is truthful – backed by no proof, although regularly found to have internally coherent results. At the same time, Locke clearly supposes the truthfulness of our senses is non-accidental although he does not try to prove it in this context. There is a strain of Christian teleology in his view of our cognitive faculties.11 They have a purpose and they function as they should in our environment because of the wisdom and providence of the creator. The faculties God has given us “. . . put within the reach of [our] Discovery the comfortable Provision for this Life and the Way that leads to a better”. (Essay I.i.5). The senses operate entirely within bounds of nature although the reason why the results are truth conducive is ultimately supernatural. One can say that Locke is not inept in his handling of skepticism about the external world. His view is, in formal respects, like what are now called “reliabilist” theories of knowledge. The schematic picture is that the truthfulness of our sensory faculty is not to be doubted, for a reason that is at least coherent. But what is the testimony of the senses? Locke says almost nothing about perceptual error. He seems to think it not much of a problem. Indeed, he indicates something to this effect in connection with our ability to know that we are awake, rather than dreaming. Whereas Descartes proposes a test to remove doubt about whether we are awake at a given moment,12 Locke acknowledges no need for one. No one has difficulty telling the difference between dreaming her hand is in the fire and having her hand in the fire (Essay IV.xi.8; IV.ii.14). In case doubt arises that we are seeing a fire, we can use our tactile sense to confirm it (Essay IV.xi.7). The general point seems to be that when sensory appearances are misleading, we use our senses to find and correct the error. Rather than undermining the truthfulness of the senses, this presupposes it. For Locke, then, the “testimony of the senses” in general can be regarded as true because it is self-correcting.13 While Locke broadly credits the senses in this way, he nevertheless strictly delimits the sorts of beliefs about which we have sensitive knowledge: © 2004 University of Southern California and Blackwell Publishing Ltd.

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“. . . when our Senses do actually convey into our Understandings any Idea, we cannot but be satisfied, that there doth something at that time really exist without us, which doth affect our Senses, and by them give notice of itself . . .”. Nor can we doubt “. . . that such Collections of simple Ideas, as we have observed by our Senses to be united together, do really exist together”. (Essay IV.xi.9). So the current or past reception of ideas, or collections of them, gives us knowledge that real things do, or did, exist when our senses are affected; but we have no certainty of their existence at other times. (See Essay IV.xi.8–11.) Further, concerning what lies outside the scope of sensitive knowledge, nowhere does Locke say that we know the tenets of his doctrine of primary and secondary qualities – that ideas are caused by primary qualities of insensible parts, that secondary qualities are nothing but powers executed in this way, that ideas of primary qualities resemble the qualities of objects that cause them whereas ideas of secondary qualities do not. In short, our senses testify to this and nothing more: that when we receive sensory ideas, we take note of particular objects which really do exist, at that time, and unite qualities corresponding to our ideas. This is a meager characterization of things we can be certain exist. But it is not nugatory. If the Cartesian evil genius exists, it is causally responsible for all our sensory ideas and there are no corporeal substances at all. We can infer that the evil genius does not exist, on Locke’s account of sensitive knowledge. This is because we know there are several different real beings that we perceive. We take note of many different things; in reality, there are things that unite powers corresponding to the collections of simple ideas we find in experience. This counts for Locke as the testimony of the senses. So, for example, when presented with a certain combination of sensory ideas, which we refer to one object and identify as horse, we can (by and large) be certain that we are in the presence of a horse; upon receiving two such combinations, a person knows she is in the presence of two different horses. This is plain from the existential propositions Locke says we know: that there exists something white and black, a paper, a man, a fire, the sun; we are certain of the “Existence of material Beings” (Essay VI.xi.2,3,7,9,11).14 Although Locke strips knowledge down to the bare existence of things with powers to produce our ideas, he nevertheless maintains that we know these things are, in reality, articulated in accord with idea-collections given in experience.15 Simple ideas of sensation, singly or in combination, deliver the testimony of our senses. The doctrine that sensitive knowledge extends to beliefs of a certain sort, and only to those beliefs, places certain demands on simple ideas. First and foremost, they ought to contribute to cognizance of the external world; they should somehow give rise to thoughts of particular things, conscious states with intentional content consisting of those things. They should also inform us as to the sameness and difference of those © 2004 University of Southern California and Blackwell Publishing Ltd.

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things, individually and with respect to their qualities; and in doing so, they should inform us nothing about the natures of these qualities. Finally, when we receive simple ideas, they should let us know that the causes of our ideas exist. The question to be pursued is how, for Locke, this basic content – directed to particular objects and minimally informative about them – is brought to the mind by simple ideas of sensation.

3. The expose of the origin of ideas in Book II is, in the nature of the case, a laying out of the intentional content conveyed by the various sorts of ideas, or objects of immediate awareness, we have according to Locke. The result of this exposition in regard to simple ideas of sensation ought to comport with sensitive knowledge, as explicated later on. For the earlier review of ideas is the basis on which a specific sort of minimal beliefs is said, in Book IV, to have the warrant conferred by our sensory faculty. Several points urged in the discussion of ideas clearly contribute to this result. We might look especially at the four chapters near the end of Book II that summarize the representative character of various classes of ideas (chapters xxix through xxxii). The handling of clarity and distinctness establishes a crucial necessary condition for Lockean sensitive knowledge. Clearness is a matter of an idea’s presenting an appearance easily discernible, exact, retainable; our ideas vary with regard to clarity. Locke briefly considers “distinctness” to be the property an idea has just in case it is distinguishable from other ideas, i.e. we can readily tell whether two ideas (tokens) are the same or different in type. But if this is what is meant, he declares, then we have no ideas that lack the property: “For let any Idea be as it will, it can be no other but such as the Mind perceives it to be; and that very perception, sufficiently distinguishes it from all other Ideas, which cannot be . . . different, without being perceived to be so.” (Essay II.xxix.5; also IV.i.4; IV.ii.1).16 Because ideas are items of immediate perception, they are intentional contents of a sort: that is, there is awareness of them.17 For Locke, as we just saw, the content that individuates sorts of ideas is readily accessible to awareness. Someone who attends to the ideas that come to mind cannot make a serious mistake as to whether they are the same or different in kind. Two idea tokens are of the same thing, then, if and only if they are alike in immediate awareness. This strong transparency and incorrigibility thesis lends support to Locke’s theory of sensitive knowledge. It assumes that sensory ideas, in general, convey, in a practically unmistakable way, that things are someway-or-other. To put the point roughly: unless we were quite clear as to what the universal testimony of the senses is, beliefs to the effect that their testimony is true could not count as knowledge, as they do for Locke. © 2004 University of Southern California and Blackwell Publishing Ltd.

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What does immediately accessible content tell us in regard to external objects? Locke pointedly withholds certainty from claims to the effect that real things resemble the sensory appearances they produce in us. Instead, I will argue, immediate content testifies regarding structural features of the world: different things, their possession of several qualities, their qualitative similarities and differences. The chapter “Of Real and Fantastical Ideas” is the first of three chapters that consider ideas “in reference to things from whence they are taken, or which they may be supposed to represent” (Essay II.xxx.1). Here, if any where, we learn how simple ideas contribute to apprehension of external things. Simple ideas of sensation, Locke says, are supposed to represent real things – they put us in mind of things we take to be real; so they are real just in case they do stand in a representative relation to such things. In explaining why all simple ideas are real, Locke is especially anxious to stress that a causal connection to real beings, absent resemblance to them, suffices for simple ideas to represent what they are “supposed” to: For these several Appearances, being designed to be the Marks, whereby we are to know, and distinguish Things, which we have to do with; our Ideas do as well serve us to that purpose . . . whether they be only constant Effects, or else exact Resemblances of something in the things themselves: the reality lying in that steady correspondence, they have with the distinct Constitutions of real Beings. (Essay II.xxx.2).

The basic explanatory argument is this: (i) simple ideas are real just in case they are marks by which to distinguish real things and their qualities; (ii) simple ideas are effects produced in us by the various powers of real things,18 (iii) so they meet the condition necessary and sufficient for them to be real. A secondary line of reasoning stresses the irrelevance of resemblance: because the causal connection suffices, simple ideas need not be “Images, or Representations” of things that exist in order to be real. This conservative view of the information conveyed by simple ideas is, of course, reflected in the later strictures on sensitive knowledge. There is a nice fit between the semantic and epistemic theories in this respect. In this explanation, nothing is said about our taking note of the causal connection in which the reality of simple ideas consists. Yet Locke evidently supposes we are aware that simple ideas represent real beings without us. It is only because sensory ideas are supposed to represent, are “tacitly referr’d” to, things existing in nature that they are real only if they correspond to external existent entities. But although Locke evidently means to say that simple ideas connect us cognitively with external objects, he may seem to say nothing about notice, or apprehension, of them. The reality-constituting connection is described from a third person point of view: simple ideas are effects “ordained by our Maker”, © 2004 University of Southern California and Blackwell Publishing Ltd.

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“intended to express nothing but the power in Things” (Essay II.xxxi.12); “designed to be the Marks” for distinguishing things (Essay II.xxx.2). What does this have to do with first person perceptual states? The whole discussion of “reality” is pervaded by the presumption that we take simple ideas to represent external objects. But by what mental operation? what role do ideas have in acts of taking directed to objects? how is immediate awareness of an idea related to awareness of an external object that is its cause? These questions threaten to make ideas a semantic barrier to the external world. Here, where the existence of real things is assumed, the fact that a person’s total sensory state, a state that encompasses simple ideas, is a cognizance of those things seems to slip out of the picture. Locke clearly wants to say that we take note of things external to our ideas, but it may seem we are left to surmise how this is done, on his view. To make matters worse, his empiricism constrains what he could consistently say about the sources of intentional content. Berkeley’s idealism rests partly on his contention that sensory ideas, objects of “immediate perception”, cannot represent – in the sense, bring to mind – anything but other ideas.19 Michael Ayers suggests Locke’s account of the representative function of simple ideas is best characterized by the theory of natural signs; causal correspondence sets simple ideas up as natural signs of the qualities, or causal powers, of external things. To him, this is one (among several) reasons to think that sensory ideas are “blank effects”, sensations as opposed to states with intrinsic intentionality. They represent solely in virtue of their causal origins. Sensations are “elements in a mental language”: they stand for things in thought, but do not, as contents of immediate awareness, point to them. As Ayers explains: “The simple appearance is taken by the mind as the sign of its unknown cause, but the mind has no choice in the matter since that is what a natural sign signifies” (Ayers, 1991, pp. 40, 62–3). It is clear that the natural sign relation is inadequate to explain the semantic relation between simple ideas and their causes. Natural signs are evidential (Ayers, 1991, pp. 40 and 62–3). A person could not use the occurrence of simple ideas as evidence that their causes exist unless she already had the ability to direct thought to the causally implicated things. Something in her mental language must already stand precisely for them. Ayers seems, then, to mean that when the mind refers a sensation to its cause, the sensation is already associated in the mind with that particular thing. The reference adds to the idea the awareness of what it stands for. But there is reason to doubt that this expresses Locke’s view. For one thing, dividing simple ideas from the interpretation the mind gives them sits uneasily with his anti-innatism.20 It seems to require that a human mind be primed to ascribe to its ideas an object that it does not apprehend from them. If the ideas exhibit nothing with regard to their objects (do not intrinsically © 2004 University of Southern California and Blackwell Publishing Ltd.

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point to them), the intentional content of the ascription would seem to come from the mind itself. An act of referring to something as the cause of an idea could be performed only by a mind that already possesses ideas of cause and effect. But Locke’s anti-innatism requires him to extract all such representational content from simple ideas of sensation. Perhaps Ayers only means that the mind refers the idea to an object that is its cause, without representing it as such. Still any act of referring a sensation to something else would seem to require some ideas in addition to the sensation. The main difficulty remains. How does a perceiver consciously apprehend external objects at all? Ayers’ account would do well enough, if sensations that represent external things were said to generate mental responses appropriate to those things, leaving awareness of them aside. But according to Locke, we consciously take notice of the objects to which simple ideas are referred. What we apprehend with regard to external objects would have to be “drawn from the mind”, which seems to play too directly into the hands of innatists.21 Locke was familiar with the philosophy of Ralph Cudworth.22 In A Treatise on Eternal and Immutable Morality, Cudworth says something about how sense perception is directed to particular things without us. He is an innatist in the manner of Descartes. Even sensory ideas are products of the mind occasioned by motions in certain parts of our bodies. As Cudworth puts it, sensations are “affections of the soul”, “fatally” (i.e. fatefully) connected with motions in some of our bodily parts, “whereby the soul perceiveth something else besides those immediate corporeal motions . . .”. We perceive things around us because the soul “is secretly instructed by nature to take notice of some other things thereby that may concern the body”.23 Again, motions in the sensory system signal the soul in such a way “that by natural instinct it takes notice of some corporeal things existing without our bodies, whence that motion upon the nerves comes, as light, colours, sound, heat and cold, hardness, softness, gravity, levity, odours, sapors.” (Cudworth, 1996, pp. 52–3). Given the currency of this sort of view, it is hard to see what difference Locke could have found between the view that the mind refers its intrinsically non-representational sensations to the objects they “naturally signify” and the view that the mind is innately “instructed” to ascribe sensible qualities to particular external objects whenever certain motions occur in the brain. It would fit better with his empiricism, if Locke meant to give sensory ideas the job instructing the mind with regard to the external objects of which they give the mind notice. But did he? The natural solution to the difficulty just mentioned is that simple ideas of sense, in themselves, direct cognition to things. That is, to have sensory ideas is thereby to take notice of particular things. Chappell takes a step in this direction by suggesting Locke might have thought that ideas come “labeled as signs, or rather as representers of the things that have caused © 2004 University of Southern California and Blackwell Publishing Ltd.

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them”; in that case: “The mind would simply be drawn or led without thought or awareness from the idea it perceives to the external object that is causally responsible for it”. (Chappell, 1994, p. 54). This, too, seems to conflict with the denial of innate knowledge, because the mind must already, as a condition of having sensory ideas, know how to read the label; that is, it must know what object to think of, e.g. the cause of this sensation.24 Moreover, it compromises the theory of representation. It would seem to be a view on which the object represented by a sensory idea is determined internally to immediate awareness. Suppose, for example, that our sensory ideas exhibit their having an external cause, and they represent whatever satisfies this accessible content. The problem is that the objects of sense perception are the very individuals that affect our sensory systems – those particular things, rather than whatever conforms to a uniquely identifying condition. Indeed, Chappell offers this as a speculation. Locke’s account of why simple ideas represent real beings, as we suppose, notably omits to say that simple ideas make us aware of the fact that they are caused by real beings without us. If Locke is to be consistent with his anti-innatism, he needs to make out that sensory ideas represent external objects, not just by corresponding to them, but also in the sense of making them available to cognizance; simple ideas need to have a constitutive role in the notice we take of particular things. In fact, I want to urge, he does ascribe a role of this sort to simple ideas. Two conditions make simple ideas real: they have a steady causal correspondence with the constitutions of things and they serve as “the Marks, whereby we are to know, and distinguish Things, which we have to do with . . .” (Essay II.xxx.2). Locke seems to mean that the marking operation performed by (or by means of) simple ideas is directed toward external things. The marking out of various qualities of things is internal to immediate awareness, but the distinctions apprehended cut to the reality of things. That is, when a person uses sensory ideas to distinguish something, she takes cognizance of an object discriminated by awareness of the sensory idea, but determined by the causal origin of her ideas. In order to serve this discriminating-function, simple ideas need not resemble objects, as Locke tells us. Nor, by the same token, need they present an immediately accessible content to which the object of cognizance uniquely conforms. The causal and marking conditions work in tandem. Simple ideas could not perform the marking function for which they were designed, if “all were a dream”, and there were no particular material things. Moreover it would not suffice for the marking function if a perceiver’s internal discriminations were merely attended by an equal-numerous multiplicity of external objects in her reach. Nothing in this would direct her cognizance to one of them, rather than another. The steady causal correspondence between ideas and external causal powers determines the objects of © 2004 University of Southern California and Blackwell Publishing Ltd.

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ideas. To be more accurate, a simple idea token, the product of a concrete causal encounter, represents the particular quality of a particular object causally responsible for the idea.25 So causal correspondence between the powers of real objects and simple ideas is necessary for their representative function. But it would be irrelevant unless we had some awareness of external objects by means of sensory ideas. We suppose ideas represent real beings without us, as Locke puts it. Apparently this is because sensory ideas are “Marks by which we distinguish Things, for our uses”. We might say that simple ideas make particular things known to us “under” appearances by which we make them out – without uniquely identifying them – in immediate awareness (see Essay IV.iv.4). This doctrine dominates, not only the discussion of the “reality”, but also the “adequacy” and “truth”, of all simple ideas, or so I would urge.26 But Locke sometimes seems to offer a different account of semantic function: simple ideas represent external objects because ideas are effects evidently caused by those objects; we are immediately aware of their causal origin. Consider these remarks from Book IV: we know “the existence of particular external Objects, by that perception and Consciousness we have of the actual entrance of Ideas from them . . .”. (Essay IV.ii.14). Again, “‘Tis therefore the actual receiving of Ideas from without, that gives us notice of the existence of other Things, and makes us know, that something doth exist at that time without us, which causes that Idea in us . . .”. (Essay IV.xi.2; also IV.xi.3). To my mind, it is not entirely clear just what Locke purports to be explicating in such passages: whether an evidential relation, a semantic one, neither, or both. But of course if a person takes the reception of an idea to be evidence that a particular thing exists, she must be able to think of that particular thing. So Locke may well not intend to explain this ability here. Still such passages may seem to be addressing a semantic issue, how simple ideas direct notice to particular things, and giving the answer, because it is immediately evident that the ideas are caused by those things. That answer would be problematic for several reasons mentioned above. Nevertheless one may suspect that Locke endorses the view that ideas, not only correspond to objects, but also direct notice to them, because the mind is immediately aware that its ideas are caused by those objects. The chapter “Of True and False Ideas” indicates differently, however. Strictly speaking, truth and falsity do not pertain to ideas, but rather to propositions, Locke observes as a preliminary. Accordingly any consideration of truth in connection with an idea presupposes that the idea is compared to something else. Suppose we compare ideas to “the real Existence of Things”. Then an idea that is supposed to be taken from, or represent, a real existent thing will be true just in case the purported thing really exists (Essay II.xxx.1; II.xxxii.5).27 Simple ideas are supposed to be represent real things, and all of them are true, Locke contends. © 2004 University of Southern California and Blackwell Publishing Ltd.

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The argument is familiar: simple ideas are appearances produced in us by the powers of external objects operating in accord with “established Laws”, and this is sufficient for simple ideas to represent what we suppose them to, i.e. to be true (Essay II.xxxii.14; also IV.iv.4). So far, it may seem that simple ideas are supposed to represent the powers of things (but not inform us of their natures) because the ideas convey that they are caused by the powers of real things (and convey nothing more). However such an impression is immediately contravened: Nor do they become liable to any Imputation of Falshood, if the Mind (as in most Men I believe it does) judges these Ideas to be in the Things themselves. For God . . . having set them as Marks of distinction in Things, whereby we may be able to discern one Thing from another . . . it alters not the Nature of our simple Idea, whether we think, that the Idea of Blue, be in the Violet it self, or in our Mind only; and only the Power of producing it . . . be in the Violet it self. (Essay II.xxxii.14).

Nor, he continues, is the idea affected, whether we think it to be the product of “a peculiar Texture of Parts” or the “exact resemblance” of a quality in the violet. Locke names two pairs of mutually inconsistent ways of construing the relation between sensory ideas and external objects. Consider the first. If most men think their simple ideas are in things, then simple ideas do not evidently convey to most of us that they are modifications in us caused by those things.28 Is Locke confused, or merely bluffing, when he tries to maintain the truth of simple ideas, in face of the obvious fact that we do tend to believe that blue, as we sense it, is in the violet?29 To think that would be to miss the point. The threat of falsity illuminates representative function. Simple ideas are effects of the powers of real things, but they make us cognizant of those things because we use them to discriminate one thing from another. In particular, simple ideas represent real things without conveying any precise relation to those things: neither existing in them, nor being caused by them, nor resembling them. The marking function is compatible with each of these ways of thinking about the idea-object relation. It works because ideas are, in fact, whether or not we realize it, effects of the powers united in particular things. It is in this way that simple ideas “answer” the powers of things and, thereby, cannot fail to be “true”. The semantic idea-object relation is, here at least, clearly separated by Locke from any evidencing relation ideas may have qua effects. Locke’s thesis that simple ideas represent, in part, because of their marking function presupposes considerable complexity and order in the contents of immediate awareness. It seems the mind uses sensory ideas to distinguish individually different objects, their various causal powers, and their qualitative similarities and differences. Nothing short of that will enable us to “take them for our Necessities, and apply them to our Uses” (Essay IV.iv.4). To this end, simple ideas of sensation need to convey a © 2004 University of Southern California and Blackwell Publishing Ltd.

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fairly stable division of particular things and distribution of qualities over them. That our simple ideas, in combination and over time, exhibit this sort of pattern is taken for granted by Locke. It is implicit in II.xxx.2, where simple ideas are said to correspond to “the distinct Constitutions of real Beings”. In context, this does not mean just a one-one mapping of ideas to real causal powers, but also repeated mappings of a number of ideas collectively united in experience to a number of powers united in the distinct constitutions of existent things. Locke understood well enough that the collections of ideas the marking function requires could only be built up over time, as the result of many mental operations. It was not in his line to speculate on exactly how this is managed; he only specifies an outcome which, he must suppose, is confirmed by the accessible content of sensory awareness. The groups ideas form in our minds comes into play as the basis for the mind’s construction of general abstract ideas of substances: “The Mind being . . . furnished with a great number of simple Ideas, conveyed in by the Senses, as they (sic) are found in exteriour things, . . . takes notice . . . that a certain number of these simple Ideas go constantly together; which [are] presumed to belong to one thing . . .”. (Essay II.xxiii.1). The theory of sensory representation in II.xxx.1 comes off, because it is Locke’s theory that, corresponding to ideas that “go together”, there is a real being that unites the several powers to cause those ideas. Since we are free to put whatever simple ideas we choose into a general abstract substanceidea, according to Locke, it cannot be said that all abstract general ideas of substances are real, by his standard. Nevertheless, we suppose general ideas of substances represent real beings in nature, and they are indeed real, provided they are: “such Combinations of simple Ideas, (sic) as are really united, and co-exist in Things without us”. (Essay II.xxx.5).30 What comes across both in this façon de parler and Locke’s way of parsing it is that simple ideas, singly and in collections, are supposed, by us, to be related to objects in an accident-like way – if they do not literally exist in objects, at least they are caused by powers that exist in them.31 Simple ideas are treated, less as neutral sensations that stand for external things, than as sensations inextricable from a characterizing relation to external things. Locke has various ways of describing this relation – belonging to things, being caused by them, having or lacking resemblance to them. Perhaps it is best expressed by “serving as marks by which we distinguish things” – individually and qualitatively. When I say simple ideas are “inextricable” from such a relation, I mean the idea cannot be divorced from its use to mark different qualities and different collections of qualities in the same thing. A person has the idea of blue, say, only if “blue” sensations serve as distinguishing marks of external objects for her. Merely having phenomenallyblue sensations, and being able to think of them as such, does not suffice to possess the idea of blue. Locke says as much in a letter to Stillingfleet: © 2004 University of Southern California and Blackwell Publishing Ltd.

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“all simple ideas, all sensible qualities, carry with them a supposition . . . of a substance in which they inhere”. (Works IV: 7). Further evidence comes from a passage on names: “The Names of simple Ideas and Substances, with the abstract Ideas in the Mind, which they immediately signify, intimate also some real Existence, from which was derived their original pattern”. In contrast, names of ideas of mixed modes immediately signify abstract ideas but “lead not the Thoughts any farther . . .”. (Essay III.iv.2). Talk of an idea’s “original pattern” fits an idea of substance, because ideas of that sort are supposed to include collections of sensible qualities united in actual things. But simple ideas, taken singly, are not copied from anything. Locke’s thought seems to be that single simple ideas carry with them the thought of some actual thing to which they are related, so to speak, as its “accident”. It is not plausible that this relation is exhibited in immediate awareness. Rather, it is internal to the essential marking function simple ideas of sensation have. One might argue that, as contents of immediate awareness assigned an essential role, simple ideas satisfy a familiar test for intentionality – being subject to evaluation for correctness. If Locke’s simple ideas are essentially marks by which we discriminate the qualitative similarities of things, which is part of the function I am urging, they ought to be type-individuated as such. There is evidence that Locke thought of simple ideas, in their capacity of representing sorts of qualities, in this way.32 It comes just before Locke introduces Molyneux’s question, where he briefly notes that mental processes sometimes affect visual awareness of the qualities of things. “[T]he Ideas we receive by sensation,” he says “are often . . . alter’d by the Judgement, without our taking notice of it”. (Essay II.ix.8). For instance, when we look at an alabaster globe, it “imprints” on us an idea “of a flat Circle” variously colored; but we have learned in experience that this sort of appearance is usually produced by convex bodies; so “the Judgement . . . alters the Appearances”, “makes it pass for a mark of Figure, and frames to it self the perception of a convex Figure, and an uniform Colour”. The appearance (idea) is presumably not altered in its phenomenal character – it remains the same bounded pattern of color, light and shade; what changes is the distinction the sensation is used to mark. Locke does not hesitate to say that this alters the idea; he seems to mean an idea of one sort is altered into an idea of a different sort. The first visual idea is of a flat circle, whereas the second is of a convex surface, i.e. type-similar to the tactual idea of convexity.33 But recall that the nature of a simple idea is not altered whether we think it is in the sphere, or caused by it, or similar to it (Essay II.xxxii.14). None of these changes alter the sort to which a token idea belongs, because they do not change the idea’s marking function.34 Cudworth maintains that sensations, in themselves, convey nothing with regard to external objects. They cause notice to be taken of certain objects because the mind is naturally instructed in a code. Sorts of cranial © 2004 University of Southern California and Blackwell Publishing Ltd.

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motions signal the mind to produce sensations and refer them to specific objects in the vicinity. Locke takes a somewhat different tack by saying that simple ideas have representative content in virtue of two conditions: (i) a steady causal link between ideas and their objects; (ii) an essential marking function in execution of which simple ideas are taken to convey something (rightly or wrongly) about the objects to which they direct notice, namely, their individual and qualitative differences and similarities. To be sure, Locke does not attempt to explain the marking-operation in detail. Some readers may well suspect that a genuinely plausible explanation would have to make concession to some sort of innatism;35 but no operation mentioned by Locke overtly requires innate ideas.

4. Locke’s account of the representative function of simple ideas ought to comport with his view of the sort of beliefs underwritten by the truthfulness of the sensory faculty. I have tried to show that he provides an account of how simple ideas contribute to cognizance of particular objects and qualities. In important respects, it is sketchy, to be sure, but so far within bounds of his explicit attack on innate ideas and his representative theory of thought. A second demand is that the senses universally and unmistakably testify to the sameness and difference of particular things and their qualities. This demand, too, is reasonably well satisfied – allowing a wave of the hand at the question how ideas are “collected”. Moreover the semantic theory also explains why the warrant of certainty does not extend to the doctrine of primary and secondary qualities; it is because the semantic function of simple ideas does not presuppose resemblance between ideas and qualities they mark. But there remains the suggestion that the evident causal origin of our sensory ideas is integral to sensitive knowledge, so that this, too, should be immediately evident when sensory ideas are conveyed into the mind. We know the existence of things “by that perception and Consciousness we have of the actual entrance of Ideas from them”. (Essay IV.ii.14). But the Book II account of the semantic aspects of simple ideas is far from supporting the suggestion that we are normally conscious that sensory ideas are effects of an external cause. As we have seen, discussion of the reality of simple ideas fails to mention it, although the opportunity is obvious, and the account of the truth of simple ideas strictly conflicts with it. Most men think their simple ideas are in things, and this does not interfere with the truth, adequacy, or reality of simple ideas. The problem is not that Locke has no way of showing that ideas are mental modifications in us, not in things. This is, after all, a basic tenet of his theory of human understanding. Perhaps in defending the distinction © 2004 University of Southern California and Blackwell Publishing Ltd.

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between primary and secondary qualities, he makes a case for the claim that colors, warmth, etc. are sensory effects that have external bodily causes.36 The difficulty is that the belief that ideas are caused from without appears not to be covered by the basic warrant of sensitive knowledge. It can hardly be part of the plain testimony of the senses, if the vulgar take from their senses an opposite belief.37 Nevertheless when sensitive knowledge is in question, Locke seems to assume that we are, in general, aware that our sensory states come from external things: “’Tis therefore the actual receiving of Ideas from without, that gives us notice of the Existence of other Things, and makes us know, that something doth exist at that time without us, which causes that Idea in us . . .”. (Essay IV.xi.2).

Yet it is not clear just how the event of receiving ideas is said here to be related to knowledge that things exist: whether as occasion, efficient or perhaps instrumental cause, or evidential ground. Moreover, the scope of what we are said to know could be regarded as ambiguous: do we know that something exists, which in fact causes our idea (whether or not we realize it) or do we know that something exists and know that it causes the idea? Still it is difficult to deny that the former reading seems strained.38 Taken overall, what Locke says about when, and by what means, we know that particular things without us exist leaves the strong impression that sensory ideas, qua effects, make evident the existence of their causes. That is, simple sensory ideas seem to be recognized as natural signs in ordinary experience, according to Locke. There are, then, two distinct strains in Locke’s epistemology of the senses: (a) the doctrine that (a specific sort of) sense-based belief regarding the existence of things without is warranted by the sensory faculty on the principle that doubt of the testimony of the senses leads to an impasse; (b) the thesis that the patently external source of sensory ideas makes it evident to virtually all human perceivers that the causes of those ideas exist. Assuming (b) is an account of the general epistemic situation, not just that of the cognoscenti, it conflicts with Locke’s acknowledgement that most men believe their ideas are in things. Still the appearance of such conflicts in Book IV might plausibly be avoided. It is natural to suppose that when Locke uses expressions like “Consciousness we have of the actual entrance of Ideas from [external objects]” and “the actual receiving of Ideas from without”, his use of “idea” is referentially transparent; he uses it to describe what a perceiver is, in fact, aware of without meaning to imply that she takes herself to be aware of it as idea. When she is in fact receiving an idea, she may suppose something less specific, perhaps that her overall sensory state is externally caused. Locke might plausibly contend that it is, not simple ideas as such, but the attendant © 2004 University of Southern California and Blackwell Publishing Ltd.

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circumstances that make us conscious of being passive in sense perception. It is obvious that we cannot entirely control what appears to our senses. Theory (b), then, might be said to require all men to be conscious, when perceiving, that they are in some way affected from without, but not to require all men to distinguish between ideas and qualities of things. A certain tension between the two epistemic doctrines remains, however. In response to skepticism about the external world, Locke offers the pragmatic considerations surrounding theory (a), without mention of theory (b) (see Essay IV.ii.14; IV.xi.3,8,10). The paramount point is the logical one, that no evident appearance that sense-based beliefs are true can be credited without relying on sense-based beliefs. For instance, theory (b) would be circular as a response to skepticism; it depends on crediting as true the sense we have that our ideas are effects produced from without. Since this, too, might be a dream, how can we be certain that ideas have a cause, as they seem to have? The warrant for this must depend, at least partly, on theory (a), in light of Locke’s handling of skepticism. The secondary status of (b) is further indicated by the strict limit on the beliefs it is capable of justifying. From the premise that our sensory ideas are received from without, it follows that there is at least one external cause of those ideas, but not that there is more than one. As we have seen, Locke claims we know there are many particular material things; the evil genius hypotheses is false. An epistemology that supports that claim requires a good deal more than the evident ground offered by theory (b). In particular, simple ideas need, not just to be recognized as natural signs, but also reliably to convey something about the variety among their causes and distribution of qualities. It makes sense for Locke to introduce theory (b) as a source of justification of the sense-based beliefs he claims we know, because he has other means of warranting the testimony of the senses. Otherwise, (b) would hardly serve his purpose. With this in mind, that theory appears as an adjunct to Locke’s main epistemic doctrine. Yet many readers have the impression that (b) is the sum and substance of Locke’s account of knowledge of the external world.39 It cannot be denied that many passages in IV.xi strongly suggest that the passive reception of sensory ideas evidentially justifies belief in the existence of things that cause ideas. While this does not necessarily indicate a confusion of theories on Locke’s part, I think it is a lapse of clear exposition that contributes to the appearance that he is vulnerable to both epistemic and semantic veil of perception charges. In closing, I want to stress the overall success of the representative theory in context of Locke’s basic account of sensitive knowledge, theory (a). Both the theory of representation and the theory of knowledge presuppose, but give no proof of, a lawful causal connection between simple ideas, collections of simple ideas, external objects and the powers they unify. Theory (b), which warrants belief by virtue of the evident external © 2004 University of Southern California and Blackwell Publishing Ltd.

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origin of ideas, distracts attention from the semantic underpinning of Locke’s theory of warrant – how do we know the evident appearance is right? Moreover the theory does not yield what Locke claims we know: that we are in the presence of many real things with various sensible qualities distributed among them. If we want to understand why beliefs of just this sort are warranted, according to Locke, we need to look to his account of sensory representation. The epistemic and semantic parts of Locke’s account complement each other, as they should.40 Department of Philosophy Rutgers University NOTES 1

Mackie, J. L. (1976). Problems from Locke. Oxford: Oxford University Press, pp. 54 –5. Yolton J. W. (1975). “Ideas and Knowledge in Seventeenth-Century Philosophy,” Journal of the History of Philosophy 13, pp. 145–65; (1970) Locke and the Compass of Human Understanding. Cambridge: Cambridge University Press, pp. 127–37; (1984) Perceptual Acquaintance from Descartes to Reid. Minneapolis: University of Minnesota Press, pp. 88– 104. For a review of the debate that helped set the context for Yolton’s discussion of the theory of ideas, see Ian Tipton, “ ‘Ideas’ and ‘Objects’: Locke on Perceiving ‘Things’”, in Margaret Atherton (ed.) The Empiricists. Lanhan, MD: Rowman and Littlefield, 1999, pp. 1–18. 3 Yolton, 1979, pp. 136–7; also pp. 130–2; Yolton, 1984, pp. 100 –2, 212–13. It is difficult to understand how “intentional objects”, which are just as we take them to be, can fail to be in us ontologically, as well as cognitively. Yolton is not unaware that the direct realism he ascribes to Locke is plagued by some ontological tensions. 4 Essay II.viii.8; II.xxxi.2. See the careful discussion of Yolton’s view in Michael Ayers (1991). Locke: Epistemology. London: Routledge, pp. 56–66 and (1986). “Are Locke’s Ideas Images, Intentional Objects, or Natural Signs?”, Locke Newsletter 17, pp. 3–36. 5 (1994) “Locke’s Theory of Ideas” in Vere Chappell (ed.) Cambridge Companion to Locke. Cambridge: Cambridge University Press, pp. 29–30. 6 He does suggest Locke might have held a certain account, which is briefly considered below; on the veil of perception problem, see Chappell, 1994, pp. 31, 54. 7 Locke recognizes no contentful mental states of which a mind has not at some time been aware; see Essay I.ii.5,8, etc. 8 Many philosophers maintain that a direct realist theory of perception withstands skeptical attack more effectively than a causal theory is able to do. 9 It is not impossible, if we have a cognitive faculty whose operations do not depend on sensory input, as Descartes, Cudworth, and others maintain. Locke recognizes no such human faculty. 10 See e.g. Gary Hatfield (1997). “The Workings of the Intellect: Mind and Psychology” in Patricia Easton (ed.) Logic and the Workings of the Mind. Atascardero, CA: Ridgeview, pp. 21– 46. 11 See G. A. J. Rogers, “Locke and the Objects of Perception”, this issue. 12 See the conclusion of Meditation VI. 13 Internal coherence seems to be regarded by Locke as a sort of justification for sensebased belief, but of a sort secondary to the warrant due to the presumed truthfulness of the sensory faculty; see Essay IV.xi.4–7. 2

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14 Locke’s claim that we know that substances of various kinds exist takes advantage of his doctrine that substantial kinds are defined by the complex idea to which a person attaches the name of the kind. It is, then, sufficient for something to be a “material thing” that it be extended and solid, if ideas of those qualities and no others are included in the operative idea of matter (Essay III.vi.2,5, etc.). 15 This is not to say the ultimate individuating principles of material things are identical to the principles by which things are distinguished, one from another, in immediate awareness, but just that the real articulation of individuals and qualities in a perceiver’s environment matches that exhibited in her experience. On the individuation of things, see Essay II.xxvii.1–2. 16 Locke accordingly defines another sense of “distinctness” in relation to words; see also “Epistle to the Reader” (Essay 27). 17 The controversial questions are whether ideas are intentional entities and whether they are intrinsically of things. 18 There is a suggestion here that ideas must have an external cause, because the mind cannot make simple ideas for itself. This seems not to play an essential part in the explanation of the reality of ideas, however. 19 See e.g. Principles of Human Knowledge, secs. 8, 25. 20 See also below, regarding whether, in fact, it is generally evident to us that sensory ideas are effects caused from without, according to Locke. 21 Ayers could reply that the full blown “testimony of the senses” is the product of experience, which provides ideas of cause and effect, or whatever else, required to refer sensations to their objects. But if ideas never exhibit content that points beyond themselves, repeated exposure to ideas will never make a person aware of anything other than those ideas. If experience produces ideas of the sort required, then it would seem to involve processes that contribute innate content of some sort. 22 Locke is known to have studied at least those portions of True Intellectual System (1685) that concern knowledge and sense perception. A Treatise on True and Immutable Nature of Morality (1731) was published after Locke’s death, but he may well have read the manuscript circulated by Damaris Cudworth. See J. A. Passmore (1951). Ralph Cudworth. Cambridge: Cambridge University Press, pp. 90 – 91. An innatist account of sense perception like that in the later treatise can be found, in much less succinct form, in the earlier work. 23 Cudworth, Ralph (1996). A Treatise concerning Eternal and Immutable Morality. Sarah Hutton (ed.) Cambridge: Cambridge University Press. 24 It may be Chappell’s proposal that ideas represent external objects without our having any awareness of those objects. But Locke is engaged to explain how we have consciousness of them. 25 The fact that token sensory ideas represent sorts of qualities, in addition to particular qualities of particular things (see Essay IV.iv.4, e.g.), raises some further issues; see Bolton, 2003. 26 Essay II.xxxi.2; II.xxxii.14–15. The argument in the former does not mention the marking function of simple ideas. In effect, it repeats the second of the two arguments we identified in II.xxx.2. I would urge that the argument in II.xxxi.2 cannot be understood apart from the full main argument in the previous chapter. Moreover, because adequate ideas are a species of real ideas (II.xxxi.1), we can infer that the two conditions for real simple ideas hold also for adequate ones. 27 An idea that is not supposed to represent any thing that exists, like those of mixed modes, are “true” by default; see Essay II.xxxii.17. 28 Also Essay II.xxxi.2. 29 Cp. Ayers, 1984, p. 20; Ayers, 1991, p. 64.

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30 For the same reason, and under the same conditions, abstract general ideas of substances are true, by Locke’s standard; see Essay II.xxxii.18. 31 Yasuhiko Tomida (2001) Inquiries into Locke’s Theory of Ideas (Hildesheim: Olms) argues that Locke’s habit of speaking of sensory ideas as if they existed in things is, not inadvertent, but rather plays a theoretical role in Locke’s account of sensory ideas. I am indebted to Tomida for making me realize that the locution has theoretical importance although I am not entirely in agreement with his account of its role. 32 See above, note 24. 33 Locke agrees with the negative answer to Molyneux’s question, as I see it, because he supposes the newly sighted man’s initial visual impressions would serve to mark no figures of external objects for him; see Martha Bolton (1994). “The Real Molyneux Question and the Basis of Locke’s Answer,” in G. A. J. Rogers (ed.) Locke’s Philosophy: Content and Context. Oxford: Oxford University Press, pp. 75–100. 34 While I think this is the right reading of this passage, the question how Locke thought simple ideas of sorts of qualities (as opposed to ideas of the particular qualities of particular things) are individuated needs more thorough discussion. 35 See Bolton, 2003. 36 Tomida, 2001 urges this view. 37 In addition to passages from Essay II.xxxii mentioned above, see II.xxxi.4; II.viii.18. 38 However Essay IV, ii, 14: 538,1–2 has no scope ambiguity. Thanks to Stewart Duncan for this point. 39 Readers of this sort include myself, in earlier work. 40 I am grateful to Vere Chappell, not only for organizing this project, but also for his comments and conversation on an earlier version of this paper during the Margaret Wilson Conference in 2002. Thanks also to Raffaella De Rosa for comments and to Ralph Schumacher for exchange of ideas on issues discussed in this paper.

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