- Locke: knowledge and its limits
- Locke: knowledge and its limits Ian Tipton I That John Locke’s Essay concerning Human Understanding is one of the philosophical classics is something nobody would deny, yet it is not easy to pinpoint precisely what is so special about it. Locke himself has been described as the founder of British empiricism, but labels of this sort are increasingly treated with suspicion, and some affinities to Descartes, usually regarded as the first of the great rationalist philosophers, have also been widely acknowledged. Students studying his philosophy will spend some time pondering on his advocacy of a distinction between primary and secondary qualities, but they will also be told that the doctrine had a long history and that, in Locke’s own day, it was central to the theorizing of Robert Boyle and the ‘new science’ generally. They may dwell too on his talk of a material substratum of qualities, but they may also be told that his thinking here was confused, and that at this point anyway he was strongly influenced by the scholastic philosophy he saw himself as trying to break away from. They are likely to be puzzled by his talk of ‘ideas’ as the Objects’ of thought—he tells us at one point that ‘the Mind…perceives nothing but its own Ideas’ (IV.iv.3)1—if only because, on the face of it, this poses the obvious problem that, as Berkeley was to stress, it seems to rule out the possibility of the very knowledge of the ‘real’ world that Locke clearly took it for granted we have. Locke himself confesses that the Essay is too long— ‘the way it has been writ in, by catches, and many long intervals of Interruption, being apt to cause some Repetitions’ (Epistle to the Reader)—and his style makes it neither easy nor attractive to read; yet it richly rewards study. That this would be agreed both by those who have thought him guilty of fundamental errors throughout and by those who see him as belonging most decidedly to our age, and as characteristically judicious and sane, merely adds to the fascination of his work and encourages deeper study. This fascination is increased when we realize that in his own time he was often considered a dangerous and subversive thinker. Locke was born at Wrington, Somerset, in 1632. He attended Westminster School and Christ Church, Oxford, where he retained his Studentship until 1684. After an introduction to the world of diplomacy when he was involved in a mission to Brandenburg he set out to qualify in medicine, working at one stage with Thomas Sydenham, the great physician whom, in the Epistle to the Reader which prefaces the Essay, he describes, along with Robert Boyle, Christiaan Huygens, the Dutch astronomer and physicist, and ‘the incomparable Mr. Newton’, as one of the ‘Master-Builders, whose mighty Designs, in advancing the Sciences, will leave lasting Monuments to the Admiration of Posterity’. Locke had worked with Boyle too, and Boyle was clearly one important influence on the Essay, just as Lord Ashley, afterwards Earl of Shaftesbury, to whom he became personal physician in 1667 and also a political adviser, influenced his personal fortunes. Locke was to serve Shaftesbury in various capacities, becoming, eventually, Secretary to the Council of Trade and Plantations, of which Shaftesbury was President. This body was dissolved in 1675. In the same year Locke’s deteriorating health led to him departing for France. He stayed first in Montpellier, but in Paris was able to make new contacts, including François Bernier, a leading disciple of Gassendi, a philosopher who had almost certainly influenced the development of his thinking, even before this period.2 Locke returned to England, and to an increasingly troubled political scene, in 1679. Before long Shaftesbury was forced to flee to Holland, where he died in 1683, and later that year Locke himself left for Holland, returning only after James II had been deposed and William of Orange had secured the English throne. Locke’s Essay was published not long after, in 1690, and it was regarded at once as both important and controversial. However, apart from engaging in a time-consuming controversy with Edward Stillingfleet, Bishop of Worcester, Locke showed little inclination to get involved in arguments with his critics, not even Leibniz, who attempted repeatedly to engage in correspondence with him, though his New Essays on Human Understanding was not published until long after the death of both men. Locke published other works after his return from Holland, including the Two Treatises of Government, discussed in the next chapter, but his health continued to fail. He was to spend the last years of his life in the house of Sir Francis Masham and his wife Damaris, daughter of the Cambridge Platonist Ralph Cudworth, and herself a woman of impressive intellect with whom Locke, a lifelong bachelor, had, it seems, once been in love. He died in 1704. Even this brief sketch of Locke’s life will be sufficient to show that it was an eventful one, and each stage had its impact on the development of Locke’s intellectual life. He did not publish anything of importance until he was in his fifties, but his Some Thoughts concerning Education (1693) reflects his critical attitude to the sort of education he had himself encountered at Westminster School. His dissatisfaction with the sort of philosophy taught at Oxford when he was there, which he described as ‘perplexed with obscure terms and useless questions’, influenced the development of the Essay, as, more positively, did his reading of Descartes who, he was to tell Stillingfleet, offered him ‘my first deliverance from the unintelligible way of talking’ of the schools. His association with Shaftesbury involved him in practical affairs, and it is no surprise that his publications should include Some Considerations of the Consequences of the Lowering of Interest, and Raising the Value of Money (1692), as well as A Letter concerning Toleration (1689), which championed religious toleration, of which Shaftesbury had been a proponent. The likely influence of Gassendi, which probably antedated Locke’s acquaintance with Bernier, has already been mentioned, and R. I. Aaron is one commentator who has stressed the influence of the Cambridge Platonists, claiming that ‘Much of the fourth book of the Essay might have been written by one of the Cambridge School’.3 One could go on, even in a way that might suggest that Locke was hardly an original thinker at all, though that would be grossly unfair. A fairer estimate would be to see him as a child of his time, certainly, but as making a major contribution to the debates and disputes which characterized the period in a way which led to a recognition of his importance at the time, though not always for the reasons that have been most widely stressed since. In very general terms, he can be seen as a spokesman for his age who also helped mould that age. In addition, he was to come to be seen, somewhat distortedly, as the originator of a school, the British empiricists, diametrically opposed to the rationalism stemming from the philosophy of Descartes. From either point of view his Essay concerning Human Understanding will be seen as an important legacy, and to that we now turn. II There are two well-known passages in the Epistle to the Reader which help focus our minds on the aims and purposes of the Essay, one being that in which Locke praises the ‘Master-Builders’, scientists such as Boyle, with respect to whom he contrasts himself as ‘an UnderLabourer…clearing Ground a little, and removing some of the Rubbish, that lies in the way to Knowledge’. This passage makes his project look modest, but it also suggests that, in so far as he sees himself as having opponents, these are not so much the Cartesians as the Aristotelians, or those proponents of the debased scholasticism which for many still constituted learning, but which was characterized by the ‘frivolous use of uncouth, affected, or unintelligible Terms’ which Locke goes on to complain of. There is much in the Essay that could be described as rubbish-removal, from the attack on innate principles in Book 1, to, for example, criticism of the doctrine of substantial forms. However, this passage does suggest that Locke’s project is negative, so it must be added both that, in practice, rubbish-removal usually goes along with positive alternative doctrines, and that in the other passage in the Epistle he gives a rather different account of his aims. Here he tells us how the Essay came to be written, referring to a meeting with friends—usually thought to have taken place in the winter of 1670–I—when an issue Very remote’ from that discussed in the Essay was being debated and they ‘found themselves quickly at a stand, by the Difficulties that rose on every side’. Locke’s response, he tells us, was to consider whether the question that perplexed them was one they could hope to resolve. More generally, he suggested, ‘it was necessary to examine our own Abilities, and see, what Objects our Understandings were, or were not fitted to deal with’. This topic set the agenda for the Essay. Locke could indeed have given his work the title ‘Human Knowledge: Its Scope and Limits’, which was the title which, over two hundred years later, Bertrand Russell gave to one of his books. Even this, however, can make Locke’s project look very negative, but what he goes on to stress in the first chapter of Book I is the positive advantages of this approach which are, first, that an enquiry into the limits of the understanding will enable us to concentrate our minds upon matters we can tackle with some hope of success, and second, and as a consequence, that we will not retreat into a general scepticism because some issues are beyond human resolution. The same chapter makes it clear that Locke does not take the thought that there are areas in which we cannot expect to have knowledge to imply that in all such areas we must expect to remain ignorant, and that he is as interested in cases where certainty is not possible for us but in which we may have reasonable beliefs. Hence his announced programme, which is ‘to enquire into the Original, Certainty, and Extent of humane Knowledge; together, with the Grounds and Degrees of Belief, Opinion, and Assent’. Hence too a feature of the Essay, that where others might see their inability to solve some problem arising from their overall position on some topic as at least a prima facie objection to that position, Locke may see such difficulties as simply confirming that our powers of comprehension are limited. Sometimes this may strike the tough-minded critic as simply dodging the issues that matter, but this is certainly not Locke’s attitude. So far, then, we know something of Locke’s purpose, but nothing of his strategy for achieving it which he sets out in I.i.3 as being, first, to ‘enquire into the Original of those Ideas, Notions, or whatever else you please to call them, which a Man observes, and is conscious to himself he has in his Mind; and the ways whereby the Understanding comes to be furnished with them’; then ‘to shew, what Knowledge the Understanding hath by those Ideas’; and finally to ‘make some Enquiry into the Nature and Grounds of Faith, or Opinion’. However, while this may seem superficially clear, it in fact gives only an imperfect guide to the overall structuring of the Essay, and it leaves certain questions unanswered, one of these being precisely what Locke means by ‘idea’. This question has vexed commentators ever since, who have not been greatly helped by the knowledge that Locke inherited the term and some of the obscurities that go with it. Locke offers some sort of explanation in I.i.8, but the overall impression one gets is that it strikes him as just obvious that we have ‘ideas’ in our minds—the ideas of, for example, whiteness, thinking, an elephant or an army—and that he is not concerned with what an idea is. Thus the important question becomes simply how we come by our ideas. His reply—‘To this I answer, in one word, From Experience’ (II.i.2)—is what has marked him out as an ‘empiricist’, or as one committed, using a dictionary definition, to ‘The theory which regards experience as the only source of knowledge’. One need not quarrel with this ascription—Locke goes on to stress that ‘In that, all our Knowledge is founded; and from that it ultimately derives it self—so long as one appreciates that, for Locke, it is experience that is the origin of ideas, or what he calls the ‘materials’ of knowledge, and that when, in book IV, he considers ‘what Knowledge the Understanding hath by those Ideas’, it might seem as appropriate to judge him a rationalist. Nor should we assume that because Locke takes it as evident that we have ‘ideas’, or conceptions, such as those of an elephant, existence or God, there is nothing problematic about his talk of ‘ideas’. Locke encourages us to take a relaxed attitude to them, and it would indeed be rash to assume at the outset that they must be images as some have thought,4 but it would be just as rash to assume that questions don’t arise concerning them. For the moment, however, we must just be clear that Book II of the Essay is not concerned with knowledge and belief as such, but with the ‘ideas’ that ground these. Locke will consider, for example, how we come by the ideas of God and existence. If we have knowledge that God exists, this will emerge in Book IV. III Though Locke announces his programme at the beginning of Book I by saying that his first concern will be with how we acquire our ideas, he in fact doesn’t address this question directly until Book II. Instead, after the first chapter in Book I, which introduces the Essay as a whole, three chapters are devoted to what may strike the modern reader as a tiresome digression: an attack on innate principles. It is important to realize, then, Both that the attack on innatism was deemed highly controversial at the time, and that these chapters complement the rest of the Essay. Putting it simply, Locke’s positive claim that all our knowledge derives from experience really amounts to a claim that no knowledge is prior to it, and this would have been seen by his contemporaries as in itself denying that some knowledge is innate. The direct attack on innatism in Book I and the working out of his empiricism in the rest of the Essay are thus two sides of one coin, and both were judged subversive, even by those who insisted that he attacked too crude a version of innatism, leaving more sophisticated versions intact. Whatever precisely they meant by this, many felt it imperative to hold that certain principles which Locke calls ‘practical’, including the fundamental principles of morality and religion, were innate if their authority was not to be jeopardised, and many were convinced that certain ‘speculative’ principles, for example ‘Whatever is, is’ must equally be ‘native’ to the mind, and indeed fundamental to knowledge in general. When, much later in the Essay Locke attacks the scholastic notion that ‘all Reasonings are ex praecognitis, et praeconcessis’, explaining that this means that certain supposedly innate maxims are ‘those Truths that are first known to the Mind’ and those upon which ‘the other parts of our Knowledge depend’ (IV.vii.8), we have an illustration of how Locke could see himself as ‘removing some of the Rubbish, that lies in the way to Knowledge’. We can also see that his attack on innatism was not peripheral to his programme. In the event Locke devotes one chapter to the supposedly innate speculative truths, one to practical truths, and, finally, one largely to innate ideas on the basis that if, for example, the knowledge that God is to be worshipped were innate, the ideas of God and worship would have to be innate too. That the ideas are not innate Locke takes to be evident. As he says, If we will attentively consider new born Children, we shall have little Reason, to think, that they bring many Ideas into the World with them. For, bating, perhaps, some faint Ideas, of Hunger, and Thirst, and Warmth, and some Pains, which they may have felt in the Womb, there is not the least appearance of any settled Ideas at all in them. (I.iv.2) Infants, then, patently lack them, but so too do some adults, both of which would be impossible were they innate. To the modern reader, one problem with Locke’s polemic is likely to be that what he takes to be obvious here—and he takes much the same line on supposedly innate principles—will seem just that, obvious, so that his attack on innatism is likely to seem unnecessarily prolix, particularly given that it might seem that nobody could seriously have held the view he attacks. Thus Descartes, for example, who we know did hold that the idea of God was innate, surely didn’t believe that every infant, or indeed every adult, has the idea consciously formed in his mind. To be fair, Descartes can be found writing in a way that suggests that the idea will be there, fully formed but not attended to—the infant has in itself the ideas of God, itself, and all truths which are said to be selfevident; it has these ideas no less than adults have when they are not paying attention to them, and it does not acquire them afterwards when it grows up but elsewhere he takes the view that what is innate is, rather, a capacity or disposition, comparable to a natural disposition to gout.5 Both notions are designed to take account of the fact that the infant does not entertain conscious thoughts about God, which might seem to cut the ground from under Locke’s objection. In fact, it is clear that neither move would trouble Locke. His tactic throughout the polemic is to take the claim that certain items of knowledge (or ideas) are in the mind from the first quite literally, so that the infant for example should be conscious of them, and then to represent any watering down of the doctrine as a retreat into obscurity or triviality. For example, dealing with the notion that what is innate is a natural capacity, he argues that ‘if the Capacity of knowing be the natural Impression contended for, all the Truths a Man ever comes to know, will, by this Account, be, every one of them, innate’, for, trivially, we must always have had the capacity to acquire any knowledge we eventually acquire, so that ‘this great Point will amount to no more, but only to a very improper way of speaking’ (I.ii.5). At this level, indeed, Locke’s attack on innatism is quite effective; it was clearly necessary, for in one form or another the doctrine that there was innate knowledge was widely received; and even if it did not once and for all end any talk of innate impressions (Leibniz for one attempted to defend it against Locke) it increasingly lost its hold. It has been claimed that ‘there has been no trace of it in recent thought’.6 IV As already stated, Book I complements the rest of the Essay in the sense that the denial of innate knowledge is merely the negative face of the positive claim announced at the beginning of Book II. It follows that Locke himself sees the direct attack as in a way superfluous to his programme (see I.ii.i), though, by the same token, he sees that the attack in Book I will be ‘more easily admitted’ once it has been shown how experience does provide a sufficient basis for our ideas (II.i.1). What follows in the rest of the Essay is thus, in part, an account of how experience gives rise to our ideas, and the knowledge based on them, though, and in a way more importantly, it is an exploration of the implications of this account. The fascination of the work as a whole thus lies in large part in what Locke has to say on a variety of issues, ranging from what sorts of achievement we can expect in natural science, to the nature of the human mind and its relation to the body, personal identity, the status of moral truths, and whether God’s existence can be proved. The emphasis throughout is of course epistemological—on what we can know and what we can reasonably surmise in this or that area—but firm conclusions are drawn, including that there is a God and that this can be proved. For the moment, however, we must stay with Locke’s basic empiricist claim. This is that all our knowledge derives from ‘experience’, but the gloss Locke immediately puts on this is important for three reasons. First, he makes it clear that there are two sources of experience, sensation and what he calls ‘reflection’, which provides the mind with ideas of its own operations, such as perception, thinking and doubting; second because the derivation of an idea from experience is not seen as always a simple matter (on the model of deriving the idea of green from seeing green things), in that it will be necessary to take ‘a full survey’ of our ideas, including ‘their several Modes, Combinations, and Relations’, or as they are ‘with infinite variety compounded and enlarged by the Understanding’ (II.i.5); and, third, because, from the outset, the existence of external objects is apparently taken for granted. Ideas of sensible qualities, such as that of yellow, are thus introduced as those conveyed into the mind ‘from external Objects’ (II.i.3), and it is not until much later (IV.xi) that Locke dwells on the notion, which he even there treats as absurd, that there may be no external objects at all. This may seem surprising given that scepticism on this matter was very much in the air at this time, and indeed that, since Berkeley at least, we have been encouraged to see Locke’s own philosophical position as positively inviting scepticism, so it needs stressing that Locke himself shows no such anxieties. It is worth noting too that the examples of ideas derived from sensation given in II.i.3—yellow, white, heat, cold, soft, hard, bitter, sweet—are all what Locke will call ‘simple’ ideas, and that this is no accident. It is an essential part of what is known as Locke’s ‘compositipnalism’ that ‘simple’ ideas are as it were the basic data, and that, given these, other, complex ideas can be formed, such as those of gold, a centaur or a lie. It would be possible to spend quite a lot of time on the distinction between simple and complex ideas, for there is no doubt that it is, at best, not as clear and straightforward as Locke seems to suggest and it has even been argued that he tacitly abandoned it when it becomes embarrassing. Here we can only note that chapters ii to viii of Book II are officially devoted to ‘simple’ ideas, that chapters ix to xi cover various faculties and operations of the mind, and that from chapter xii on Locke turns to ‘complex’ ideas. That it is not, however, the issue of Locke’s basic compositionalism that is of most interest or importance is suggested by the fact that many of the topics that have most engaged readers then and since can be examined without paying special attention to it.7 There is much in Book II we could linger on, and some things that we shall. Book II of the Essay is in fact a mine of interesting and often important material, though the significance of much of it can only be fully understood in terms of the philosophical concerns of the time, and even then the significance may not be immediately recognizable, at least from the titles of the relevant chapters. Thus, the unpromising title of chapter xiii, for example, is ‘Of simple Modes; and first, of the simple Modes of Space’, but it includes Locke’s rejection of the Cartesian claim that a vacuum is inconceivable, building on a distinction between the ideas of body and space established in chapter iv, as well as observations on the notion of substance, though this will not be the main focus of interest until chapter xxiii. Similarly, chapter viii has the unexciting title ‘Some farther Considerations concerning our Simple Ideas’, but it is here that we find Locke’s classic defence of a distinction between primary and secondary qualities. Chapter xxi—‘Of Power’—includes a long discussion of human freedom; while if we want to know how Locke takes the idea of God to be derived from experience, we must look to four sections (33–6) almost hidden away towards the end of chapter xxiii. One could go on. Suffice it to say that, though the Essay as whole can strike one as rambling and diffuse, so that it becomes tempting to focus on the isolated topics which interest one, the work is better approached as a whole. Certainly, one needs to be alert to various developing themes. V Just which themes are the most important must be to some extent a matter of opinion, and it is certainly true that what was judged most significant in Locke’s own day often differs from what has most exercised commentators more recently. This is hardly surprising, given Locke’s successes in removing what he saw as rubbish, which has meant that what seemed to be important issues then have often ceased to exercise our minds since. Indeed this may be the point to reiterate that in his own time Locke was often regarded as subversive,8 to the extent that some were inclined to suspect a not too well hidden agenda. Stillingfleet or Leibniz could be cited here, but as good an example as any would be another critic, Thomas Burnet, who devoted the first of three sets of published Remarks on the Essay to polite queries, but who concluded the third set by laying his cards on the table and accusing Locke of not doing the same. The ‘key’ to deciphering Locke’s philosophy, indeed ‘the mystery aimed at all along’, is he suggests, the supposition ‘that God and matter are the whole of the universe’. For Burnet, Locke emerges as a deist, whose system provides for only an inadequate conception of both God and the human soul. Shortly afterwards Berkeley was yet another to be struck by what he saw as dangers implicit in Locke’s philosophy, but he was only one of many to be struck by Locke’s suggestion that matter might think. In fact, this particular suggestion occurs in just one section (IV.3.6), where Locke presents it only as an illustration of how limited our knowledge is, and it would be rash to assume that there was a hidden agenda. However, the suggestion can be seen as a natural culmination of much that had gone before. It provides one key, though certainly not the only one, to unravelling some of the intricacies of the Essay. Thus the modern reader approaching even the first chapter of Book II may find it odd that, in defending his claim that we are dependent on experience for our ideas, Locke devotes many sections to an attack on the notion that the soul always thinks, either prior to an individual’s first sensory experiences, or during the course of his life. For, while there is an obvious connection here with Locke’s basic empiricist programme and his rejection of innatism, what we may miss is the significance of the fact that Locke is also undermining the notion that thought is the soul’s essence. For Descartes at least, this notion was central to a proof that the soul was immaterial, so it is unsurprising that those immersed in this tradition could see Locke’s attack on it, and indeed his attack on innatism too, as closely connected with doubts about the soul’s immateriality. Indeed, the dangers could only become more apparent when, in II.xxiii, Locke makes it clear that we are ultimately in the dark about what the soul’s essence is. Here there is alink between his observations on corporeal substance, or the supposed substratum of sensible qualities, which we shall return to, and his comments on the substance underlying mental operations, when he claims that, like the substance of body, ‘The substance of Spirit is unknown to us’ (sect. 30). Admittedly, chapter xxvii, which was added in the second edition, is for the most part devoted to an account of personal identity which attempts to disentangle the idea of the continuance of a person from that of the persistence of any particular sort of substance, and he will hold in IV.iii.6 that our belief in immortality is not threatened whatever the nature of the soul. But the upshot is that Locke can find no proof of the natural immortality of the soul. For Locke, of course, this emerges as one illustration of the limits of human knowledge. For many readers, the dangers were clear.9 VI There is, however, a much more dominant theme running through the Essay, which connects indeed with the last but underlies much that Locke says in Books II, III and IV, for many of Locke’s concerns centre on what might best be described as an exploration of the implications of the corpuscular science associated in particular with Boyle. In Book II, two topics to which this concern is clearly very central are his treatment of primary and secondary qualities in II.viii, and of our idea of substance in II.xxiii. Both have given rise to much discussion, and indeed—with the possible addition of II.xxvii (on personal identity)—these have probably been the most widely discussed chapters in Book II. They are, I think, best treated together, though very often they have been treated separately. Certainly, that Locke’s concern in II.viii is with the implications of the new science can hardly be denied given what he himself says in section 22 where, after noting that “I have in what just goes before, been engaged in Physical Enquiries a little farther than, perhaps, I intended’, he adds that this was necessary, to make the Nature of Sensation a little understood, and to make the difference between the Qualities in Bodies, and the Ideas produced by them in the Mind, to be distinctly conceived, without which it were impossible to discourse intelligibly of them. Nor is it deniable that the natural philosophy Locke has in mind here is the corpuscular system, which, as Locke explicates it, entails that our ideas of colours, odours and tastes for example correspond to secondary qualities, which are but powers in objects depending on ‘the Bulk, Figure, Texture, and Motion of their insensible parts’ (sect. 10). There is indeed much that is problematic in Iviii—for example the implications of his claim that our ideas of primary qualities, but not of secondary qualities, are ‘resemblances’ of them, but the centrality of the new science to what Locke says is evident. What this opposes is, basically, Aristotelian science, which would account for our perception of colours for example by reference to the forms of the colours in the objects, so it seems reasonable to suppose that when Locke complains that Men are hardly to be brought to think, that Sweetness and Whiteness are not really in Manna; which are but the effects of the operations of Manna, by the motion, size, and figure of its Particles on the Eyes and Palate (sect. 18) the men he has in mind will include, not just ordinary folk, but supporters of a soon to be defunct metaphysics. Even if we accept that, however, there is much that could be discussed. It might be asked, for example, what right Locke had to appeal to the new science for the distinction, given that the new science remained controversial; how, if the ‘minute parts’ which are central to the story are ‘insensible’, we could know anything at all about them; and how Locke’s view that some of our ideas are, and some are not, ‘resemblances’ of qualities could ever be established, given, what he will say later, that ‘the Mind…perceives nothing but its own Ideas’. Here, so far as the first of the questions is concerned, it must suffice to say that Locke’s general attitude to the corpuscular hypothesis is that it is the best available (IV.iii.16); that, so far as the particles being ‘insensible’ goes, Locke takes this insensibility to be a merely contingent matter, which would be overcome if our senses were more acute; and that, ultimately it seems, his claims about which ideas are and which are not resemblances of qualities could be justified only in terms of an acceptance of the underlying scientific theory. All we need to add perhaps is that this acceptance was not simply dogmatic. Given this theory, and the distinction between ideas that goes with it, facts such that the same water can feel warm to one hand and cool to the other could be accounted for (II.viii.21).10 The question of what exactly Locke means when he says that ‘the Mind…perceives nothing but its own Ideas’, is perhaps better left for a while. There is more than one way of understanding it. For the moment it is more important that we note that notions that figure prominently in II.viii do re-emerge in II.xxiii, where the attention of commentators has often been focused more on what Locke says about our idea of substance in general, particularly in the earlier sections, than on the topic suggested by the title, which is ‘Of our Complex Ideas of Substances’. On the first of these issues Locke talks of our “obscure and relative Idea of Substance in general’ as ‘something… standing under’, or supporting qualities; but on the second, where his concern is with our ideas of particular sorts of substances such as gold, his claim is that we form these ‘by collecting such Combinations of simple Ideas, as are by Experience and Observation of Men’s Senses taken notice of to exist together, and are therefore supposed to flow from the particular internal Constitution, or unknown Essence of that Substance’. As is so often the case with Locke’s Essay, there has been no clear concensus on precisely what is going on in this chapter,11 but there is growing agreement that what he is struck by is the unhelpfulness of philosophical theorizing in terms of the abstract categories of substance and accident, even though he sees our ordinary ways of talking about objects as reflecting an idea of ‘something’ underlying the observable qualities of things. Suggestions such as that if we had ‘Senses acute enough’ we would ‘discern the minute particles of Bodies, and the real Constitution on which their sensible Qualities depend’ (sect, 11) give us a very obvious link with II.viii, and underwrite the view that, for Locke, speculations about substance in general bring us to the area of ‘obscure terms and useless questions’, contrasting with the intelligible theorizing of the new science. It remains the case, however, that we have here an area where, in Locke’s reasonable seventeenth-century view, the limits of human understanding are clear. Had we ‘Senses acute enough’ we would indeed be able to penetrate into the inner natures of things, but the truth is that we don’t. VII The programme announced in I.i.3 would lead one to expect that, having dealt with the ‘materials’ of knowledge, Locke would next consider knowledge itself. But, as he says at the very end of Book II, he has been struck by the fact that ‘there is so close a connexion between Ideas and Words…that it is impossible to speak clearly and distinctly of our Knowledge…without considering, first, the Nature, Use, and Signification of Language’. In Book III, therefore, he gives us his account of language. The basic picture he offers in the first two chapters in Book III is fairly simple. Words are not necessary for thought itself, but primarily in order for men to communicate their thoughts to others, or ‘to record their own Thoughts for the Assistance of their own Memory’ (III.ii.2). Words, or significant sounds, are therefore signs of our internal conceptions, and can ‘properly and immediately signify nothing but the Ideas, that are in the Mind of the Speaker’ (sect. 4). Men do, however, give them a secondary or ‘secret’ reference in that, precisely because language is used to communicate, they assume that the words they use to signify their own ideas mark the same ideas in the minds of those they converse with, while, ‘Because Men would not be thought to talk barely of their own Imaginations, but of Things as they really are’ they often take them to stand for ‘the reality of Things’ (sect. 5). Locke’s cautionary words at this point—‘it is a perverting the use of Words, and brings unavoidable Obscurity and Confusion into their Signification, whenever we make them stand for any thing, but those Ideas we have in our own Minds’—may strike us as simply perverse—surely if I say ‘John is bald’ I do mean to refer to John himself, but the implications of the remark become much clearer later. Sticking for the moment with the opening chapters, it is necessary only to add that Locke is very conscious that most words do not signify only particular, individual things. Many stand for general ideas. There are, however, nine chapters still to come in Book III, and it must be said at once that here, as quite often in the Essay, one becomes conscious of a mismatch between what probably most interests Locke himself—the points he most wants to get across— and what has most caught the attention of critics and commentators since. This can indeed be illustrated by the fact that Book III ends with three chapters on the ‘abuses’ and ‘imperfections’ of words, and the ‘remedies’ for these, which are clearly important to Locke, given his overall aims, though they have concerned commentators less. It is, however, also apparent even if one turns to chapter iii, which is certainly the most widely discussed. It is entitled ‘Of General Terms’. Clearly the topic of general terms, and the general ideas which they signify, is important to Locke, if only because, as will become plain in Book IV, most of our knowledge will be found to consist in general propositions; but, since Berkeley at least, what has most caught the attention of commentators has been his account of what might be termed the mechanics of abstraction, or the process by which Locke takes it we form general ideas. Taking the word ‘man’ as an example, Locke holds that children will start with the ideas of individuals—Peter, James, Mary and Jane—and then, having noted certain resemblances, frame an idea in which they ‘leave out…that which is peculiar to each, and retain only what is common to them all’. Berkeley was to devote the bulk of the Introduction to the Principles to attacking abstraction, insisting, for example, that ‘the idea of man that I frame to my self, must be either of a white, or a black, or a tawny, a straight, or a crooked, a tall, or a low, or a middle-sized man’ and that ‘I cannot by any effort of thought conceive the abstract idea above described’, and his criticisms have often focused minds on this aspect of Locke’s thought. By contrast, what seems to matter most to Locke is the distinction between real and nominal essences which he spells out later on in the chapter, to which the account of abstraction is a prolegomenon. Certainly, this distinction brings us right back to a dominant theme which we have already looked at, for ‘the real Essences of corporeal Substances’ are located in the ‘real, but unknown Constitution of their insensible Parts, from which flow those sensible Qualities, which serve us to distinguish them one from another’ (sect. 17). And the dominant notion that emerges now is that we rank things into sorts, neither on the basis of these real essences, which we do not know, nor on the basis of the real essences of the scholastics, which they think of as ‘a certain number of Forms or Molds, wherein all natural Things, that exist, are cast, and do equally partake’ (ibid.), but rather according to what Locke calls ‘nominal’ essences. These are, indeed, the abstract ideas already covered, but the crucial thought is that we categorize things into sorts on the basis of certain observed properties which we choose to associate as constituting one sort. Negatively, then, the dominant concern of the chapter is another piece of rubbishremoval, in this case the ‘real essences’ or ‘forms’ of the schools;12 positively it is an account of classification according to which ‘the sorting of Things, is the Workmanship of the Understanding’ (sect. 12). More generally, and as we shall see, the account prepares the way for what Locke will say about the science of nature in Book IV. There is of course much more in Book III, including treatments of the names of simple ideas in chapter iv, of the names of mixed modes and relations (‘adultery’ and ‘gratitude’ are among the examples) in chapter v, of the names of substances again in chapter vi, and of particles (words such as ‘but’ and the ‘is’ of predication) in chapter vii, but this book concludes with the three chapters on remedying ‘abuses’ and ‘imperfections’. Recalling the concern Locke expressed in his Epistle to the Reader about ‘the learned but frivolous use of uncouth, affected, or intelligible Terms’, we can understand that these chapters are not peripheral to Locke’s purposes, and his reference here to ‘gibberish’ such as the Epicurean notion of ‘endeavour towards Motion in their Atoms, when at rest’ (III.x.14) can serve as just one example of the sort of thing he has in mind. In fact he casts his net wide. His observation that, in common use, ‘body’ and ‘extension’ stand for distinct ideas, but that ‘there are those who find it necessary to confound their signification’ (sect. 6) is an obvious reference to the Cartesians.13 VIII Given that one of the main aims of the Essay is to determine the scope of human knowledge, it perhaps comes as something of an anticlimax that, in the event, Locke allows very little that he will count as knowledge. That this will be so is strongly suggested by the very first chapter in Book IV where he defines ‘knowledge’ as ‘the perception of the connexion and agreement, or disagreement and repugnancy of any of our Ideas’, giving as the first two examples ‘White is not Black’ and ‘the three Angles of a Triangle are equal to two right ones’. Locke in fact holds that the first of these involves one of four sorts of agreement or disagreement on which knowledge can be based— ‘Identity, or Diversity’—while the second is based on what he calls ‘relation’. The other sorts of perceived agreement are ‘Co-existence, or necessary connexion’ (one example given is that ‘Iron is susceptible of magnetical Impressions’, which, in so far as we know it, will turn out to be construed as what we would now term an analytic proposition), and ‘Real Existence’, the one example given in IV.i being ‘GOD is’. When we find that in chapter ii he tells us that the primary ways of knowing are ‘intuition’ (anyone who has the two ideas will simply see that white is not black) and ‘demonstration’, of which mathematical proofs are the favoured model, the strong rationalist streak in Locke becomes apparent. Indeed, for him, ‘intuition’, or self-evidence, lies at the root of nearly all he recognizes as ‘knowledge’, for demonstration turns out to be based on nothing more than a series of intuitions. A good illustration of how this is supposed to work would be the series of supposed intuitions which he offers in IV.x as constituting a demonstration that God exists. Locke, then, offers a very restrictive account of ‘knowledge’, and as the chapters proceed we find as much attention being given to things we cannot hope to know with certainty as to what we can. Examples of things lying beyond the scope of our knowledge thus turn out to include that man cannot be nourished by stones (IV.vi.15)—the explanation here being that our idea of man is that of ‘a Body of the ordinary shape, with Sense, voluntary Motion, and Reason join’d to it’ and we can neither intuit nor demonstrate by our reason any ‘necessary connexion’ between that and what will nourish him—and that opium will make a man sleep (IV.iii.25), but these could be multiplied. The proposition that gold is malleable for example is indeed certainly known to be true, but only if, as Locke puts it, ‘Malleableness be a part of the complex Idea the word Gold stands for’. If we happen not to include malleability in the definition of gold, or in the abstract idea, this again is something that cannot certainly be known (IV.vi.9). As he puts it in IV.viii.9, the general Propositions that are made about Substances, if they are certain, are for the most part but trifling, and if they are instructive, are uncertain, and such as we can have no knowledge of their real Truth, how much soever constant Observation and Analogy may assist our Judgments in guessing. There are indeed some areas where Locke’s insistence that we lack ‘knowledge’ is, if not uncontroversial, at least such as to reflect a not unreasonable caution, as for example his denial that we know that matter cannot think, but equally there are many that seem surprising. If I am not now perceiving any men, for example, Locke will deny that I ‘know’ there are other men in the world (IV.xi.9). One question that arises here, then, is precisely why Locke tolerates an account of knowledge that is as restrictive as this. And here no doubt at least part of the answer must be that he simply accepts a tradition whereby ‘knowledge’ does require a very high degree of certainty, and is indeed tied to the notion of necessity. However, this judgement must be tempered by three further observations. One is that, for all his parsimony when it comes to recognizing ‘knowledge’, he does allow some items that, to us, may seem less certain than they did to him. The second is that in some cases where he is bound to say we do and perhaps always will lack ‘knowledge’, he is still guided by a view of what acquiring knowledge in these cases would be like. And the third is that, though he sees that, with the requirements for ‘knowledge’ set this high, our ‘knowledge’ will be very limited, he also insists that what we are then bound to call ‘probability’ may be of a very high order indeed. These three points are essential to an understanding of Locke’s overall position, so I shall elaborate on them briefly in turn. First, then, it is indeed true that Locke denies that we ‘know’ certain things we would normally suppose we knew, but what we also find is that there are two areas of fundamental importance in which he believes demonstrability is attainable. The obvious example here is his supposed proof of the existence of God which, though flawed, he took to be a sound demonstration, but we should note too his repeated claim that ‘Morality is capable of Demonstration, as well as Mathematicks’ (III.xi.16, cf. IV.iii.18, IV.iv.7 and IV.xii.8). To be sure, Locke never claimed to have developed the system he envisaged, but the mere fact that he thought it possible in principle is significant. For if, starting from God’s existence, and the supposed self-evidence of a creature’s obligations to his creator, man could come by certainty in this area at least, ‘knowledge’ would certainly transcend the trivial. As he put it as early as I.i.5, How short soever [men’s] Knowledge may come of an universal, or perfect Comprehension of whatever is, it yet secures their great Concernments, that they have Light enough to lead them to the Knowledge of their Maker, and the sight of their own Duties. Indeed, the second point connects with this, for if Euclidean geometry is seen as providing the model for a demonstrative morality, it is also the model of what it would be like to have certainty in natural philosophy. For here, Locke’s insistence that we don’t for example ‘know’ that hemlock will always kill is combined with thoughts about what would be knowable to one who could penetrate into the real essences of substances. Hence his observation in IV.iii.25 that could we but penetrate into the internal structure of things ‘we should know without Trial several of their Operations one upon another, as we do now the Properties of a Square, or a Triangle’ (IV.iii.25). His assertion that ‘Could any one discover a necessary connexion between Malleableness, and the Colour or Weight of Gold…he might make a certain universal Proposition concerning Gold in this respect’ thus goes along with pessimism about the possibility of our discovering any such a connection, but also with a view about what such a discovery would be like. As he has it, ‘That all Gold is malleable, would be as certain as of this, The three Angles of all right-lined Triangles, are equal to two right ones’ (IV.vi.10). The strong rationalist streak in Locke is thus evident here, in his pessimism about our acquiring much by way of ‘knowledge’ in this area, quite as much as it is in his optimism about the possibility of a demonstrative morality, but it also connects with his lack of any deep concern that our ‘knowledge’ is, on his view, limited. And this brings us to the third point, which concerns the stress he put on the notion that ‘probability’ is not to be despised. For, on Locke’s account, to deny that I ‘know’ that man cannot be nourished by stones turns out to be no more than to assert that this truth is not self-evident or demonstrable, not that ‘constant Observation and Analogy’ don’t justify the high degree of assurance we in fact have, let alone that there are reasonable grounds for doubt. The tone here was in fact set back in I.i.5 with his observation that we should ‘not peremptorily, or intemperately require Demonstration, and demand Certainty, where Probability only is to be had, and which is sufficient to govern all our Concernments’, and the same note is struck later, in IV.xi.10. A truth may be ‘plain and clear’, though not strictly ‘known’. IX It would thus be a mistake to describe Locke as a sceptic, at least solely on the basis that he denies us ‘knowledge’ in certain areas where we would normally suppose we had it.14 Admittedly there are areas in which he thinks our lack of understanding goes deep—‘We have the Ideas of Matter and Thinking, but possibly shall never be able to know, whether any mere material Being thinks, or no’ (IV.iii.6), and we simply don’t understand for example ‘how any size, figure, or motion of any Particles, can possibly produce in us the Idea of any Colour, Taste, or Sound whatsoever’ (IV.iii.13)—but in matters that affect our practice, such as that stones will not nourish us, all we lack is demonstrative proofs. The most that can be said is that there may be one particular area where Locke should have been more sceptical than he was. This brings us back to the area of ‘real existence’, and in particular to sensitive knowledge. The truth here is that, though when he introduces his account of knowledge in IV.i the only example Locke gives of our knowledge of real existence is our demonstrative knowledge that God exists, he in fact recognizes not only our supposedly intuitive knowledge of our own existence (IV.ix.3), but knowledge of the existence of external objects. Admittedly, the scope of this knowledge turns out to be very limited—broadly I ‘know’ that an object exists only when I actually sense it—but all the same it has often been questioned whether Locke is entitled to claim even this. There are two difficulties here. One is that Locke defines ‘knowledge’ as the perception of the agreements and disagreements of ideas, and it seems doubtful that this can allow for ‘knowledge’ of the existence of anything which is not itself an idea, whether God, oneself, or any external thing; and the second is whether he is entitled to claim even an assurance of the existence of bodies, given his apparent belief that we never perceive any. This second difficulty is at best tangentially connected with the definition of ‘knowledge’, and would arise even without it. His notorious comment in IV.iv.3 that ‘the Mind…perceives nothing but its own Ideas’ raises it very forcibly, while bringing us back to the topic of Locke’s idea of ‘idea’. On the first of these supposed difficulties, all that can be said here is that it seems that Locke himself did not think that his definition ruled out any knowledge of ‘real existence’, in that he supposed the existence of God at least could be demonstrated by attending solely to our ideas. What is supposedly established here is, apparently, still a relationship between two ideas, those of God and of real existence. He makes a similar point to Stillingfleet in defending his position on sensitive knowledge,15 though in the Essay itself there are indications that he does have some misgivings about whether, strictly, this should countas ‘knowledge’ at all.16 Even there, however, he certainly claims that in this area ‘we are provided with an Evidence, that puts us past doubting’, so the real issue is whether he was entitled to claim even that. At this stage it is the second difficulty that becomes acute. Very often, traditionally even, Locke has been seen as adopting a Representative Theory of Perception which positively invites scepticism in this area. If ‘the Mind…perceives nothing but its own Ideas’ it seems we do not perceive tables and chairs, and this appears to make their existence genuinely questionable. That Locke himself shows little sign of anxiety about this hardly lessens the difficulty. Unfortunately we can do little more than note this apparent problem, apart from observing that it is of some historical importance (Berkeley’s idealism will have it as its starting-point) and that there has been much controversy on just what view of perception Locke is committed to. Whether those commentators are right who claim that Locke’s ideas of sense are ‘objects’ or ‘entities’, and indeed the only objects of which we are ever aware, rather than ‘perceptions’, or states of awareness of the things themselves, lies beyond the scope of an introductory essay. What must at least be conceded, however, is that there is undeniably a strong streak of what might be called ‘perceptual realism’ in Locke; that in many passages he does talk of perceiving the external things, and that even the claim that ‘the Mind…perceives nothing but its own Ideas’ can be interpreted in the light of his talk of ideas as being ‘found’ in the things themselves.17 Perhaps, but only perhaps, Locke is simply inconsistent, but claims such as that ‘we immediately by our Senses perceive in Fire its Heat and Colour’ (II.xxiii.7) and suggestions that what we do not perceive is the corpuscular structuring on which these qualities depend are significant. A strong case can be made for the view that the key to Locke’s thinking lies there. X It goes without saying that there is much in Locke’s Essay that has not been discussed here. That however is inevitable. His interest is perennial and his importance clear, but just what most interests a particular reader will depend on a number of factors. To his contemporaries his attacks on what he saw as ‘rubbish’ lying in the way to knowledge were of genuine significance, while the perceived implications of his epistemology for theology could and did cause deep concern. The importance he himself attached to, for example, his attack on ‘enthusiasm’ in religion in IV.xix is, though it was only introduced in the fourth edition, evident from its vigour, but the chapter is omitted from a recent abridgement. We now know that Berkeley was soon to attack the very notion of ‘matter’, or of bodies existing without the mind, and though he certainly wasn’t just addressing Locke, Locke has often been seen as his prime target. Locke’s doctrines concerning ideas have thus come to be seen as a stepping-stone to Berkeley’s idealism and indeed to Hume’s scepticism. His accounts of abstract ideas, primary and secondary qualities, substance and so on have been examined over and over again in the light of Berkeley’s criticisms, while others see them as significant in their own right. Again, Locke’s account of personal identity has been no more than touched on here, but he was the first to raise the issue in the form in which it continues to be discussed today, and his contribution is admired and, still, widely discussed. Other features of his position have been warmly praised—one commentator claims that he handles the notion of real essence ‘almost flawlessly’18—yet often he has been used for target practice, and Gilbert Ryle once suggested, though perhaps not wholly seriously, that ‘nearly every youthful student of philosophy both can and does in about his second essay refute Locke’s entire Theory of Knowledge’.19 I imagine that few, certainly few who have delved at all deeply into his thinking, would now second that sort of judgement, but for all that the correct interpretation of his position remains a matter of controversy at almost every point. This is perhaps hardly surprising, for Locke stands at a crucial point in the development of the history of philosophy, epitomizing the shift from ways of thinking that have become largely foreign to us, to ways that seem familiar. University courses entitled ‘History of Modern Philosophy’ thus customarily have Locke’s Essay as their first text originally written in English. His problems have become, in a sense, our problems. Yet we find them emerging from a background that has become less familiar. Getting the most out of Locke’s philosophy will therefore involve using hindsight, for we know its fruits, but also understanding the world from which it emerged. It is only if we do both that Locke’s true genius can be seen. NOTES 1 References to the Essay are to the Clarendon Edition, [3.3], and cite book, chapter and section number. Except in the case of the Epistle to the Reader the italics have been left unchanged. 2 In his John Locke ([3.22], 31–5), first published in 1937, R.I.Aaron noted Leibniz’s comment that Locke ‘writes obviously in the spirit of Gassendi’, and argued that the influence of Gassendi’s thought on him was considerable. Further discussions include Kroll, [3.52], and Michael, [3.56]. 3 Aaron, [3.22], 27. However, both he and Gibson, [3.25], 236–41, also draw attention to important differences of view. For one thing, most of the Cambridge Platonists held that there were innate ideas, and as Gibson notes ‘nothing, Cudworth declared, could more directly promote atheism than the Aristotelian maxim, “Nihil est in intellectu quod non fit prius in sensu”’. 4 As will emerge, for Locke we have ideas in sense experience, and also in thinking and reasoning. The question of whether ideas are images can therefore emerge at two levels. Some have held that he takes the immediate object of perception when we see or otherwise perceive an object to be itself an image, or an entity which somehow stands proxy for the object, while others seem more concerned with whether the ideas that we might now call concepts are images. No doubt the relationship between these two issues is important, but it seems fair to say that most often it has been his view of sense perception that has exercised his readers, though it is ideas as concepts that feature most prominently in the Essay. When, however, Ayers claims ([3.21], 1:44) that, ‘the grounds for holding him an imagist are conclusive’, it is clear from the context both that he regards this judgement as controversial, and that his eye is fixed on ideas as they function in thought. Certainly, the nature of Locke’s idea of ‘idea’ continues to be much discussed. 5 For an examination of Descartes’s doctrine of innate ideas, which includes the relevant passages, see Anthony Kenny, Descartes: A Study of His Philsophy, New York, Random House, 1968, ch. 5. 6 Mabbott, [4.26], 80. Even when this was published, however, a debate was in progress over Noam Chomsky’s claim that his work in linguistics vindicated the rationalists on this issue. This claim was controversial, and it was widely criticized. See, for example, D.E.Cooper, ‘Innateness: Old and New’, Philosophical Review 81 (1972): 465–83. 7 Which is not to say that nothing is lost. Aaron, [3.22], 110–14, and Gibson, [3,25], ch. 3, are among commentators who have played down its importance, but for a survey which takes it seriously, see Stewart, [3.58]. Locke’s compositionalism and its historical background also looms large in, for example Schouls, [3.38], and Ayers, [3.44]. 8 This notion did not rest only on what he wrote in the Essay, nor simply on the issue I shall concentrate on here. His publication of a work entitled The Reasonableness of Christianity in 1695 fuelled doubts as to his orthodoxy, particularly on doctrines such as those of original sin and the Trinity, while his correspondence with Stillingfleet focused attention on the supposed theological implications of the Essay. 9 This is well documented by Yolton, [3.15], 148–66, cf. [3.40], ch. 1 and passim, and [3.41]. If, from our standpoint it might seem absurd that Locke’s contemporaries made so much of a suggestion that is far from prominent in the Essay, we should be clear that things looked very different then, as they did to Leibniz for example. His reaction is examined by Jolley, [3.37], who argues that ‘For all its apparent randomness and lack of direction, the New Essays on Human Understanding is a book dedicated to defending the idea of a simple, immaterial and naturally immortal soul’ (p. 7). 10 This is among a number of phenomena instanced in II.viii. 16–21, which have, since Berkeley at least, often been read as revealing Locke’s acceptance of what is called ‘the argument from the relativity of perception’ to prove or demonstrate the subjectivity of certain supposed qualities. For a quite different, and more plausible account, see Alexander, [3.35], 124–9. 11 See for example Ayers, [3.43], including the references given on p. 78, n. 2. 12 This is just one of a number of references in the Essay to the substantial forms of the schools. For example, in IV.iv.13 Locke again protests the view that ‘there were a certain number of these Essences, wherein all Things, as in Molds, were cast and formed’. It is strongly arguable that commentators who fail to attach due importance to Locke ‘s dissatisfaction with this scholastic notion can only misunderstand many of Locke’s better known pronouncements, including not only a problem he raises earlier in IV.iv—that of how we can know that our ideas ‘agree with Things themselves’—and his answer to it as it relates to our ideas of substances, but also his insistence that words signify ideas, the account of knowledge given in Book IV, and even the content of II.xxiii. There too, in section 3, we find a significant reference to the suspect ‘substantial forms’ of the schools. (For a brief account of the doctrine, as understood by Locke and his contemporaries, see Woolhouse, [3.33], sect. 12.) 13 These examples are of ‘abuses’, but Locke’s treatment of the ‘imperfections’ of words is also important. His initially puzzling insistence that ‘Words…can properly and immediately signify nothing but the Ideas, that are in the Mind of the Speaker’ underlies his analysis of the difficulties we get into with the names of mixed modes (such as ‘murder’) and substances, and the remedies for these. An illustration is a dispute between physicians he reports on in III.ix.16 over ‘whether any Liquor passed through the Filaments of the Nerves’. This was largely resolved when they saw that ‘each of them made [the term ‘liquor’] a sign BIBLIOGRAPHY Collected Works 3.1 In progress: The Clarendon Edition of the Works of John Locke, Oxford, Clarendon Press, 1975–. 3.2 The Works of John Locke, London, T.Tegg, et al., 1823, 10 vols. Editions of the Essay 3.3 Nidditch, P.H. (ed.) An Essay concerning Human Understanding, Oxford, Clarendon of a different complex Idea’. 14 References to Locke as a sceptical philosopher that are found in the literature are, however, not wholly unjustified if they are linked to his observations about the limits of human understanding and, in particular, to his claims about our inability to penetrate into the real essences of things. The one point I want to insist on is that, for Locke, the claim that I don’t ‘know’ for example that stones won’t nourish me does not entail suspension of judgement, nor any suggestion that there are reasonable grounds for doubt. 15 Locke, [3.2], 4:360. 16 Thus Locke’s account of the ‘degrees’ of our knowledge in IV.ii dwells on intuition and demonstration, and he observes at the beginning of section 14 that ‘These two…are the degrees of our Knowledge; whatever comes short of one of these, with what assurance soever embraced, is but Faith, or Opinion, but not Knowledge’. On the face of it, this should rule out knowledge of the existence of things ‘without us’, for in the same section he admits that this falls short of ‘either of the foregoing degrees of certainty’. All the same, it ‘passes under the name of Knowledge’, and this is something Locke immediately endorses. Similarly, his observation in IV.xi.3 that in this area we have ‘an assurance that deserves the name of Knowledge’ is not unnaturally read as conceding that he is making it ‘knowledge’ by special dispensation. 17 Locke’s only sustained treatment of our knowledge of the existence of things ‘without us’ is in IV.xi, so it should be noted that here as in other key passages (e.g. II.viii.12) there is no suggestion that we do not perceive such objects. Indeed, it is said at the outset that it is ‘when by actual operating upon him, it makes it self perceived by him’ that a man knows that an external object exists. This is the sort of thing one has in mind when one talks of a strong streak of perceptual realism in Locke, but it has of course been recognized by those who hold that it cannot be taken at face value. The issue then becomes, I think, whether other things Locke says suggest that, really, all we are aware of is mind-dependent items, or whether the dominant thought is simply that, though we are aware of the things, the way they appear to us will depend in large part on facts about our sensory apparatus. For an analysis of the issues that divide commentators here, see Tipton, [3.59]. 18 Bennet, [3.36], 120. 19 Ryle [3.57], 147. The remark, made in conversation with Bertrand Russell, was set in the context of a recognition that ‘Locke made a bigger difference to the whole intellectual climate of mankind than anyone had done since Aristotle’. The paper in which he reports it is thus not dismissive, but rather Ryle’s attempt to explain what Locke’s great contribution was. Press, 1975. 3.4 Yolton, J.W. (ed.) An Essay Concerning Human Understanding (abr. edn), London, Dent, 1976. Early Criticisms 3.5 Burnet, Thomas Remarks upon an Essay concerning Humane Understanding, London, 1697, Second Remarks (1697), and Third Remarks (1699); ed. G. Watson as Remarks on John Locke, Doncaster, Brynmill Press, 1989. 3.6 Carroll, William A Dissertation upon the Tenth Chapter of the Fourth Book of Mr. Locke’s Essay (etc.) , London, 1706; repr. Bristol, Thoemmes, 1990. 3.7 Lee, Henry Anti-Scepticism: Or, Notes upon each Chapter of Mr. Lockeys Essay (etc.), London, 1702; repr. New York, Garland, 1978. 3.8 Leibniz, G.W. New Essays on Human Understanding, first pub. 1765, trans. and ed. P.Remnant and J.Bennett, Cambridge, Cambridge University Press, 1981. 3.9 Lowde, James A Discourse concerning the Nature of Man…, London, 1694; repr. New York, Garland, 1979. 3.10 Norris, John Cursory Reflections upon a Book call’d, an Essay concerning Human Understanding. Appended to his Christian Blessedness, London, 1690; repr. New York, Garland, 1978. 3.11 Sergeant, John Solid Philosophy Asserted, against the Fancies of the Ideaists, London, 1697; repr. New York, Garland, 1984. 3.12 Stillingfleet, Edward A Discourse in Vindication of the Doctrine of the Trinity, London, 1696. 3.13——The Bishop of Worcester’s Answer to Mr. Locke’s Letter, concerning some Passages relating to his Essay (etc.), London, 1697. 3.14——The Bishop of Worcester’s Answer to Mr. Locke’s Second Letter…, London, 1698. 3.15 Yolton, J.W. John Locke and the Way of Ideas, Oxford, Oxford University Press, 1956. (A survey of many early responses.) Bibliographies 3.16 Christophersen, H.O. A Bibliographical Introduction to the Study of John Locke, Oslo, 1930; repr. New York, Franklin, 1968. 3.17 Hall, R. and Woolhouse, R. Eighty Years of Locke Scholarship, Edinburgh, Edinburgh University Press, 1983. 3.18 The Locke Newsletter, published annually since 1970 by Roland Hall of the Department of Philosophy at the University of York, contains a ‘Recent Publications’ section. Biographies 3.19 Fox Bourne, H.R. The Life of John Locke, London, 1876; repr. Bristol, Thoemmes, 1991. 3.20 Cranston, M. John Locke: A Biography, London, Longmans, 1957. General Surveys 3.21 Ayers, M.R. Locke, 2 vols, London, Routledge, 1991. 3.22 Aaron, R.I. John Locke, 1st edn 1937; 3rd edn, Oxford, Clarendon Press, 1971. 3.23 Brandt, R. (ed.) John Locke: Symposium Wolfenbüttel 1979, Berlin, de Gruyter, 1981. 3.24 Duchesneau, F. L’Empirisme de Locke, The Hague, Nijhoff, 1973. 3.25 Gibson, J. Locke’s Theory of Knowledge and its Historical Relations, Cambridge, Cambridge University Press, 1917. 3.26 Mabbott, J.D. John Locke, London, Macmillan, 1973. 3.27 Mackie, J.L. Problems from Locke, Oxford, Clarendon Press, 1976. 3.28 O’Connor, D.J. John Locke, New York, Dover, 1967. 3.29 Squadrito, K. Locke’s Theory of Sensitive Knowledge, Washington, University Press of America, 1978. 3.30 Tipton, I.C. (ed.) Locke on Human Understanding: Selected Essays, Oxford, Oxford University Press, 1977. 3.31 Webb, T.E. The Intellectualism of Locke, Dublin, 1857; repr. Bristol, Thoemmes, 1990. 3.32 Woolhouse, R.S. Locke’s Philosophy of Science and Knowledge, Oxford, Blackwell, 1971. 3.33——Locke, Brighton, Harvester, 1983. 3.34 Yolton, J.W. Locke and the Compass of Human Understanding, Cambridge, Cambridge University Press, 1970. Comparative Studies and Special Themes 3.35 Alexander, P. Ideas, Qualities and Corpuscles: Locke and Boyle on the External World, Cambridge, Cambridge University Press, 1985. 3.36 Bennett, J. Locke, Berkeley, Hume: Central Themes, Oxford, Clarendon Press, 1971. 3.37 Jolley, N. Leibniz and Locke: A Study of the New Essays on Human Understanding, Oxford, Clarendon Press, 1984. 3.38 Schouls, P.A. The Imposition of Method: A Study of Descartes and Locke, Oxford, Clarendon Press, 1980. 3.39 Yolton, J.W. Perceptual Acquaintance from Descartes to Reid, Oxford, Blackwell, 1984. 3.40——Thinking Matter: Materialism in Eighteenth-Century Britain, Oxford, Blackwell, 1984. 3.41——Locke and French Materialism, Oxford, Clarendon Press, 1991. Articles and Chapters 3.42 Ashworth, E.J. ‘Locke on Language’, Canadian Journal of Philosophy 14 (1984): 45–73. 3.43 Ayers, M.R. ‘The Ideas of Power and Substance in Locke’s Philosophy’, first pub. 1975, repr. in [3.30], above. 3.44 Ayers, M.R. ‘Locke’s Logical Atomism’, in Rationalism, Empiricism and Idealism, ed. A.Kenny, Oxford, Clarendon Press, 1986. 3.45 Barnes, J. ‘Mr. Locke’s Darling Notion’, Philosophical Quarterly 22 (1972): 193– 214. 3.46 Bennett, J. ‘Substratum’, History of Philosophy Quarterly 4 (1987): 197–215. 3.47 Buchdahl, G. ‘Locke: Narrowing the Limits of Scientific Knowledge’, ch. 4 in his Metaphysics and the Philosophy of Science, Oxford, Blackwell, 1969. 3.48 Curley, E.M. ‘Locke, Boyle, and the Distinction between Primary and Secondary Qualities’, Philosophical Review 81 (1972): 438–64. 3.49 Flew, A. ‘Locke and the Problem of Personal Identity’, Philosophy 26 (1951): 53– 68. 3.50 Harris, J. ‘Leibniz and Locke on Innate Ideas’, first pub. 1974, repr. in [3.30], above. 3.51 Kretzmann, N. The Main Thesis of Locke ‘s Semantic Theory’, first pub. 1968, repr. in [3.30], above. 3.52 Kroll, R.W.F. ‘The Question of Locke’s Relation to Gassendi’, Journal of the History of Ideas 45 (1984): 339–59. 3.53 Jackson, R. ‘Locke’s Distinction between Primary and Secondary Qualities’, Mind 38 (1929): 56–76. 3.54 Laudan, L. ‘The Nature and Sources of Locke’s Views on Hypotheses’, first pub. 1967, repr. in [3.30], above. 3.55 Mandelbaum, M. ‘Locke’s Realism’, Essay 1 in his Philosophy, Science and Sense Perception, Baltimore, John Hopkins Press, 1964. 3.56 Michael, F.S. and E. ‘The Theory of Ideas in Gassendi and Locke’, Journal of the History of Ideas 51 (1990): 379–99. 3.57 Ryle, G. ‘John Locke’, first pub. 1967, repr. in his Collected Papers, vol. 1, London, Hutchinson, 1971. 3.58 Stewart, M.A. ‘Locke’s Mental Atomism and the Classification of Ideas’ (in two parts), The Locke Newsletter 10 (1979): 53–82, and 11 (1980): 25–62. 3.59 Tipton, I.C. ‘ “Ideas” and ”Objects“: Locke on Perceiving ”Things” ’, in Minds, Ideas, and Objects: Essays on the Theory of Representation in Modern Philosophy, ed. P.D.Cummins and G.Zoeller, Atascadero, Calif., Ridgeview Publishing Company, 1992. 3.60 Wilson, M.D. ‘Superadded Properties: The Limits of Mechanism in Locke’, American Philosophical Quarterly 16 (1979): 143–50. 3.61 Winkler, K.P. ‘Locke on Personal Identity’, Journal of the History of Philosophy 29 (1991): 201–26.
Routledge History of Philosophy. Taylor & Francis e-Library. 2005.