1. THE IDENTIFICATION OF PARTICULARS
 We think of the world as containing particular things some of which are independent of ourselves; we think of the world's history as made up of particular episodes in which we may or may not have a part; and we think of these particular things and events as included in the topics of our common discourse, as things about which we can talk to each other. These are remarks about the way we think of the world, about our conceptual scheme. A more recognizably philosophical, though no clearer, way of expressing them would be to say that our ontology comprises objective particulars. It may comprise much else besides.
Part of my aim is to exhibit some general and structural features of the conceptual scheme in terms of which we think about particular things. I shall speak, to begin with, of the identification of particulars. I shall not, at the moment, try to give a general explanation of my use of the word 'identify' and associated words, nor of my use of the word 'particular'. This latter word certainly has a familiar core, or central area, of philosophical use, even if the outer boundaries of its application are vague. So all I need say for the moment is that my use of it is in no way eccentric. For instance, in mine, as in most familiar philosophical uses, historical occurrences, material objects, people and their shadows are all particulars; whereas qualities and properties, numbers and species are not. As for the words 'identify', 'identification', &c., these I shall use in a number of different, but closely connected, ways and I shall try to explain each of these uses as I introduce it.
The application of the phrase 'identification of particulars' which I shall first be concerned with is this. Very often, when two
people are talking, one of them, the speaker, refers to or mentions some particular or other. Very often, the other, the hearer, knows what, or which, particular the speaker is talking about; but sometimes he does not. I shall express this alternative by saying that the hearer either is, or is not, able to identify the particular referred to by the speaker. Among the kinds of expressions which we, as speakers, use to make references to particulars are some of which a standard function is, in the circumstances of their use, to enable a hearer to identify the particular which is being referred to. Expressions of these kinds include some proper names, some pronouns, some descriptive phrases beginning with the definite article, and expressions compounded of these. When a speaker uses such an expression to refer to a particular, I shall say that he makes an identifying reference to a particular. It does not follow, of course, from the fact that a speaker, on a given occasion, makes an identifying reference to a particular, that his hearer does in fact identify that particular. I may mention someone to you by name, and you may not know who it is. But when a speaker makes an identifying reference to a particular, and his hearer does, on the strength of it, identify the particular referred to, then, I shall say, the speaker not only makes an identifying reference to, but also identifies, that particular. So we have a hearer's sense, and a speaker's sense, of 'identify'.
It is not merely a happy accident that we are often able, as speakers and hearers, to identify the particulars which enter into our discourse. That it should be possible to identify particulars of a given type seems a necessary condition of the inclusion of that type in our ontology. For what could we mean by claiming to acknowledge the existence of a class of particular things and to talk to each other about members of this class, if we qualified the claim by adding that it was in principle impossible for any one of us to make any other of us understand which member, or members, of this class he was at any time talking about? The qualification would seem to stultify the claim. This reflexion may lead to another. It often enough happens that the identification of a particular of one kind is made to depend on the identification of another particular of another kind. Thus a speaker may, in re-
ferring to a certain particular, speak of it as the thing of a certain general kind which uniquely stands in a certain specified relation to another particular. He may, for example, refer to a house as 'the house that Jack built' or to a man as 'the assassin of Abraham Lincoln'. In such cases, the hearer's identification of the first particular depends on his identification of the second. He knows what particular is referred to by the identifying phrase as a whole because he knows what particular is referred to by a part of it. The fact that the identification of one particular often depends in this way on the identification of another is not very significant in itself. But it suggests the possibility that the identifiability of particulars of some sorts may be in some general way dependent on the identifiability of particulars of other sorts. If this were so, the fact would have some significance for an inquiry into the general structure of the conceptual scheme in terms of which we think about particulars. Suppose, for instance, it should turn out that there is a type of particulars, b , such that particulars of type b cannot be identified without reference to particulars of another type, a , whereas particulars of type a can be identified without reference to particulars of type b . Then it would be a general characteristic of our scheme, that the ability to talk about b-particulars at all was dependent on the ability to talk about a-particulars, but not vice versa. This fact could reasonably be expressed by saying that in our scheme a-particulars were onto-logically prior to b-particulars, or were more fundamental or more basic than they. It seems, perhaps, unlikely that dependence, in respect of member-identifiability, of one type of particulars on another, should take the direct and simple form I have just suggested, unlikely, that is, that it should be generally impossible to make identifying references to particulars of the relatively dependent type without mentioning particulars of the relatively independent type. But there may be other and less direct ways in which the identifiability of one type of particular is dependent on that of another.
 What are the tests for hearer's identification? When shall we say that a hearer knows what particular is being referred to by a
speaker? Consider first the following case. A speaker tells a story which he claims to be factual. It begins: 'A man and a boy were standing by a fountain', and it continues: 'The man had a drink'. Shall we say that the hearer knows which or what particular is being referred to by the subject-expression in the second sentence? We might say so. For, of a certain range of two particulars, the words 'the man' serve to distinguish the one being referred to, by means of a description which applies only to him. But though this is, in a weak sense, a case of identification, I shall call it only a story-relative, or, for short, a relative identification. For it is identification only relative to a range of particulars (a range of two members) which is itself identified only as the range of particulars being talked about by the speaker. That is to say, the hearer, hearing the second sentence, knows which particular creature is being referred to of the two particular creatures being talked about by the speaker; but he does not, without this qualification, know what particular creature is being referred to. The identification is within a certain story told by a certain speaker. It is identification within his story; but not identification within history.
We need a requirement stringent enough to eliminate relative identification. The hearer, in the example, is able to place the particular referred to within the picture painted by the speaker. This means that in a sense he can place the particular in his own general picture of the world. For he can place the speaker, and hence the speaker's picture, in that general picture of his own. But he cannot place the figures, without the frame, of the speaker's picture in his own general picture of the world. For this reason the full requirement for hearer's identification is not satisfied.
A sufficient, but not necessary, condition of the full requirement's being satisfied is -- to state it loosely at first -- that the hearer can pick out by sight or hearing or touch, or can otherwise sensibly discriminate, the particular being referred to, knowing that it is that particular. This condition I shall slightly liberalize to cover certain cases where one cannot at the very moment of reference sensibly discriminate the particular being referred to -- owing, for example, to its having ceased or disappeared -- but could do so a moment before. Such cases will be among those in
which 'that' is a more appropriate demonstrative than 'this'; as when one says 'That car was going very fast', or 'That noise was deafening'. In general, then, this sufficient condition is satisfied only in the case of particulars which one can perceive now, or at least could perceive a moment ago. It is obvious that there are many cases of identification falling under this condition. An expression is used which, given the setting and accompaniments of its use, can properly, or at least naturally, be taken, as then used, to apply only to a certain single member of the range of particulars which the hearer is able, or a moment before was able, sensibly to discriminate, and to nothing outside that range. Cases of this kind are the cases, par excellence, for the use of demonstratives, whether helped out by descriptive words or not; though, of course, the use of demonstratives is not confined to cases of this kind, and expressions of other kinds may also be used in these cases. I shall say, when this first condition for identification is satisfied, that the hearer is able directly to locate the particular referred to. We may also speak of these cases as cases of the demonstrative identification of particulars.
It is obvious that not all cases of identification of particulars are cases of demonstrative identification in the sense which I have just given to this phrase. In this fact lies the ground of an old worry, which is both practically and theoretically baseless. The reasons for its practical and its theoretical baselessness are in the end the same. The nature of this worry and the reasons for its baselessness must now be made plain.
Demonstrative identification of a particular is not always an easy matter. The scene may be blurred, its elements confused. Different sections of the scene may be very like each other, and so may the items to be discriminated; and it is easy to make mistakes in applying such descriptions as 'the twelfth man from the left in the fifteenth row from the top'. Nevertheless one thing at least is clear in demonstrative identification: viz, the identity of the range of particulars, of the sector of the universe, within which the identification is to be made. It is just the entire scene, the entire range of particulars now sensibly present. (It may be said that its limits may be different for speaker and hearer. I leave the reader
to solve any problems raised by this fact.) There can be no question as to which scene we are talking about, though there may be question enough as to which part of it, which element in which part of it, and so on. These are questions which we have the linguistic means of settling.
But now consider the cases where demonstrative identification, in the sense I have given to this phrase, is not possible, because the particular to be identified is not within the range of those sensibly present. What linguistic means of identification have we available? We can use descriptions or names or both. But it is no good using a name for a particular unless one knows who or what is referred to by the use of the name. A name is worthless without a backing of descriptions which can be produced on demand to explain its application. So, it may seem, in the non-demonstrative identification of particulars, we depend ultimately on description in general terms alone. Now one may be very well informed about a particular sector of the universe. One may know beyond any doubt that there is only one particular thing or person in that sector which answers to a certain general description. But this, it might be argued, does not guarantee that the description applies uniquely. For there might be another particular, answering to the same description, in another sector of the universe. Even if one enlarges the description so that it incorporates a description of the salient features of the sector of the universe concerned, one still lacks a guarantee that the description individuates. For the other sector might reproduce these features too. However much one adds to the description of the sector one knows about -- its internal detail and its external relations -- this possibility of massive reduplication remains open. No extension of one's knowledge of the world can eliminate this possibility. So, however extensive the speaker's knowledge and however extensive the hearer's, neither can know that the former's identifying description in fact applies uniquely.
To this argument it may be replied that it is not necessary to know that the identifying description applies uniquely. All that is necessary, in order for identification to be secured, is that the hearer should come to know, on the strength of the speaker's
words, what, or which, particular the speaker is in fact referring to. Now for a speaker to use the words of a description with a certain reference, and for a hearer to understand them as making a certain reference -- whether or not the intended reference and the understood reference are in fact the same -- it is at least required that each should know of a particular which the description fits. (Or the hearer may at that instant learn, from the speaker's words, of such a particular.) But each may know of only one such particular; and each may have conclusive reason to suppose that the other knows of only one such particular, and that the particular the other knows of is the same as the particular he himself knows of. Or, even if this condition is not satisfied in full, each may still have conclusive reasons for thinking that the particular which one is referring to is the same as the particular which the other takes him to be referring to.
This reply is adequate to show the practical baselessness of doubts about the possibility of non-demonstrative identification, where such doubts have their ground in the foregoing argument. But the reply concedes too much and explains too little. It does not explain the possibility of our having the conclusive reasons we may have. It yields no clues to the general structure of our thinking about identification. It is better, if we can, to meet the argument on its own theoretical terms; for by doing so we may learn something of that general structure.
To meet the argument on its own terms, it is sufficient to show how the situation of non-demonstrative identification may be linked with the situation of demonstrative identification. The argument supposes that where the particular to be identified cannot be directly located, its identification must rest ultimately on description in purely general terms. But this supposition is false. For even though the particular in question cannot itself be demonstratively identified, it may be identified by a description which relates it uniquely to another particular which can be demonstratively identified. The question, what sector of the universe it occupies, may be answered by relating that sector uniquely to the sector which speaker and hearer themselves currently occupy. Whatever the possibilities of massive
reduplication in the universe, these possibilities create, from the point of view of identification, no theoretical difficulties which cannot theoretically be overcome in this way.
Now we can see why the previous reply conceded too much. It conceded, in the face of the argument from the possibility of reduplication, that, where non-demonstrative identification was in question, we could never be sure that an identifying description in fact applied uniquely; and then claimed that this did not matter, in view of other things we could be sure of. The reply did not say exactly what these other things might be. But now, in seeing what they might be, we see also that the argument from the possibility of reduplication has no force at all to show that we cannot be sure that an identifying description in fact applies, uniquely. For non-demonstrative identification may rest securely upon demonstrative identification. All identifying description of particulars may include, ultimately, a demonstrative element.
The solution raises a further question. Is it plausible to suppose -- unless indeed we are to fall back on relative identification -- that of every particular we may refer to there is some description uniquely relating it to the participants in, or the immediate setting of, the conversation in which the reference is made? The particulars we refer to are so very diverse. Can we plausibly claim that there is a single system of relations in which each has a place, and which includes whatever particulars are directly locatable? To this question the reply, very general at first, may run as follows. For all particulars in space and time, it is not only plausible to claim, it is necessary to admit, that there is just such a system: the system of spatial and temporal relations, in which every particular is uniquely related to every other. The universe might be repetitive in various ways. But this fact is no obstacle in principle to supplying descriptions of the kind required. For by demonstrative identification we can determine a common reference point and common axes of spatial direction; and with these at our disposal we have also the theoretical possibility of a description of every other particular in space and time as uniquely related to our reference point. Perhaps not all particulars are in both time and
space. But it is at least plausible to assume that every particular which is not, is uniquely related in some other way to one which is.
 This is a theoretical solution to a theoretical problem. We do not in fact regard ourselves as faced with the possibility of massive reduplications of patterns of things and events. Nevertheless, the fact that the theoretical solution is available, is a very important fact about our conceptual scheme. It shows something of the structure of that scheme; and it has a connexion with our practical requirements in identification.
The connexion may not be obvious. It seems that the general requirements of hearer-identification could be regarded as fulfilled if the hearer knew that the particular being referred to was identical with some particular about which he knew some individuating fact, or facts, other than the fact that it was the particular being referred to. To know an individuating fact about a particular is to know that such-and-such a thing is true of that particular and of no other particular whatever. One who could make all his knowledge articulate would satisfy this condition for particular-identification only if he could give a description which applied uniquely to the particular in question and could nontautologically add that the particular to which this description applied was the same as the particular being currently referred to; but we need not insist that the ability to make one's knowledge articulate in just this way is a condition of really knowing who, or what, a speaker is referring to. This, then, is the general condition for hearer-identification in the non-demonstrative case; and it is obvious that, if a genuine reference is being made, the speaker, too, must satisfy a similar condition. To rule out merely 'story-relative' identification, we must add a further requirement: viz, that the known individuating fact must not be such that its statement essentially involves identifying the particular in question by reference to someone's discourse about it, or about any other particular by reference to which it is identified.
Now how are these conditions satisfied in practice? We may note, to begin with, that they would be amply satisfied by anyone who could give such descriptions as would alleviate the theoretical
anxieties discussed in section . The conditions just laid down are formally less exacting than those anxieties: whatever would allay the latter in a particular case would also meet the former. But we can conclude nothing decisive from this; it was admitted that those anxieties were, in practice, unreal. So the connexion between our theoretical solution and the satisfaction of our practical requirements is still not obvious.
It might seem, indeed, remote. Surely we do not know, or need to know, of every particular we refer to or understand another's reference to, an individuating fact which relates it uniquely to the present situation of reference, to objects or people which figure in that situation? But we must consider whether this suggestion is really as absurd as it sounds. Of course we do not often, in practice, explicitly relate the particulars of which we speak to ourselves or to other items in the present situation of reference. But this fact may show no more than a justified confidence that there is no need for such explicit indications; since the circumstances of a conversation, the participants' knowledge of each other's background, are in general such that a lot may be taken for granted. Again we may sometimes be content with 'story relative' identifications, not caring for anything more, not wishing, at least at the moment, to fit the spoken-of particulars directly into the framework of our knowledge of the world and its history.
Yet it cannot be denied that each of us is, at any moment, in possession of such a framework -- a unified framework of knowledge of particulars, in which we ourselves and, usually, our immediate surroundings have their place, and of which each element is uniquely related to every other and hence to ourselves and our surroundings. It cannot be denied that this framework of knowledge supplies a uniquely efficient means of adding identified particulars to our stock. This framework we use for this purpose: not just occasionally and adventitiously, but always and essentially. It is a necessary truth that any new particular of which we learn is somehow identifyingly connected with the framework, even if only through the occasion and method of our learning of it. Even when the identification is 'story-relative', the connexion
with the framework remains, through the identity of the storyteller. When we become sophisticated, we systematize the framework with calendars, maps, co-ordinate systems; but the use of such systems turns, fundamentally, on our knowing our own place in them; though a man can lose his place, and have to be told it. Such systems, developed or embryonic, help us to escape from story-relative identification to full identification. Of course, nothing in what I say has the consequence that a man is unable to identify a particular unless he can give precise spatio-temporal locations for it. This is by no means required. Any fact uniquely relating the particular to other, identified elements in the framework will serve as an individuating fact. A description, itself in no way locating, may be known to individuate within a very extensive spatio-temporal range of particulars; all that is then required is that that range should itself be located in the framework at large.
But why, it may be asked, accord any pre-eminence to spatiotemporal relations to a common point of reference? Are there not other kinds of relation enough which will serve the same purpose? All that is formally required is a kind of relation such that, given an already identified object, O, it is possible for us to know that there is, in fact, only one thing answering to a certain description which is related by that relation to O. Does not almost any relation which one thing may have to another thing satisfy this not very exacting requirement? Indeed, some relations carry a guarantee that there is only one such thing. Thus, though we may indeed know, perhaps by being told, that there is in fact only one bridge across a certain stretch of river, we know without being told that there cannot be more than one man who is a certain man's paternal grandfather.
To this it may be replied that the system of spatio-temporal relations has a peculiar comprehensiveness and pervasiveness, which qualify it uniquely to serve as the framework within which we can organize our individuating thought about particulars. Every particular either has its place in this system, or is of a kind the members of which cannot in general be identified except by reference to particulars of other kinds which have their place in it; and every particular which has its place in the system has a unique
place there. There is no other system of relations between particulars of which all this is true. Indeed any antithesis between this and other systems of relations between particulars would be a false antithesis. Though we may freely depend on heterogeneous relations in framing identifying descriptions, the system of spatiotemporal relations remains the groundwork of these additions; most other relations between particulars incorporate spatiotemporal elements, involve or are symbolized by spatio-temporal transactions, the relative movements of bodies.
A general doubt may remain. The formal conditions of identification are satisfied if an individuating fact is known about the particular concerned. But why should such an individuating fact be such as to relate the particular concerned in any way to other items in that unified framework of knowledge of particulars of which each of us has a part in his possession? Descriptions can be framed which begin with phrases like 'the only.. .' or 'the first. . .' and thus proclaim, as it were, the uniqueness of their application. Let us call them 'logically individuating descriptions'. No doubt, in general, logically individuating descriptions will also incorporate proper names of persons, or place-names, or dates, and thereby relate the particulars they apply to to other items in the unified framework of knowledge of particulars; or, if they contain none of these, they will in general incorporate demonstrative indications, or will rely in some way on the setting of their use to assist in determining their reference. But we can also frame logically individuating descriptions which are altogether free from such features. Let us call these 'pure individuating descriptions'. 'The first boy in the class' is not a pure individuating description, for it depends on the context of its use to determine its application. 'The first dog to be born in England in the nineteenth century' is not a pure individuating description, for it contains a date and a place-name. But 'the first dog to be born at sea' is a pure individuating description; so is 'the only dog to be born at sea which subsequently saved a monarch's life'. Besides pure individuating descriptions we may recognize a class of quasi-pure individuating descriptions, which depend on the setting of their utterance to determine their application only in the sense that their application
is restricted to what existed before or exists at the same time as the moment of utterance. They are like pure individuating descriptions with the addition of the words 'so far'. An example of a quasi-pure individuating description would be 'the tallest man who ever lived'. Now surely, it might be said, we can sometimes know that a pure or quasi-pure individuating description has application; and granted that such a phrase has application, its acceptance by both hearer and speaker is sufficient to guarantee that each understands by it one and the same particular. Our individuating thought about particulars need not, therefore, involve incorporating them in the single unified framework of knowledge of particulars.
But one who makes this objection is himself in the position of remote and impractical theorist. There are many replies to him. Suppose a speaker and a hearer claimed to have identified a certain particular by agreement on a pure or quasi-pure individuating description; and suppose they accompanied the claim with the remark that they knew nothing else whatever about the particular in question. That is to say, they were quite unable to locate the particular concerned within any definite spatio-temporal region of the common framework, however extensive, or to connect it in any definite way with any item which they could so locate; they were quite unable even to relate it to any occasion of discourse which they could connect with some item in the common spatiotemporal framework. They could not, for example, say that either of them had been authoritatively told of it. In general, they disclaimed any ability to connect the particular of which they claimed to speak with their general unified framework of knowledge of particulars, and disclaimed any ability to recognize any such connexion, if it were to be suggested to them, as one which they had been aware of, but had forgotten. There would appear to be an element of frivolity in any such claim, so accompanied. In the first place, we should be inclined to infer, from the accompanying disclaimer, that the speaker and hearer had in fact no grounds, except those of general probability, for thinking that the pure individuating description had application at all. A pure individuating description, like any other logically individuating
description, may fail of application not only when there are no candidates for the title, but also when there are two or more candidates with equally good and hence mutually destructive claims and no candidate with a better claim. Thus the description, 'the first dog to be born at sea', would fail of application not only if no dog was born at sea, but if the first two dogs to be born at sea were born simultaneously. We may indeed increase the improbability of the second kind of application-failure by adding to the detail of the description; but we thereby increase at the same time the probability of the first kind of application-failure. The only safe way, in general, to elaborate the description sufficiently to eliminate the one risk, without increasing the other, would be to draw on our actual knowledge of stretches of the world and its history; but in so far as we do this, we can no longer sincerely claim to be unable to connect our description at any point with items belonging to the unified framework of our knowledge of particulars. This first reply, then, is tantamount to disputing that it is possible to know an individuating fact about a particular unless something is known about the relations of that particular to identified items in the spatio-temporal framework. It might be possible, with sufficient ingenuity, to produce cases which would circumvent this objection. But other objections would then arise. Even if it were possible to satisfy the formal conditions of particular-identification in a way which left the particular completely detached and cut off, as it were, from the general unified framework of knowledge of particulars, the achievement would be a peculiarly useless one. So long as our knowledge of it retained this completely detached character, the particular would have no part to play in our general scheme of knowledge; we could for example, learn nothing new about it except by learning new general truths. I do not think we need pursue the question any further; for it is obvious enough that the possibility envisaged, if it is one, plays no significant part in our general scheme of knowledge of particular things.
We may agree, then, that we build up our single picture of the world, of particular things and events, untroubled by possibilities of massive reduplications, content, sometimes, with the roughest
locations of the situations and objects we speak of, allowing agreed proper names to bear, without further explanation, an immense individuating load. This we do quite rationally, confident in a certain community of experience and sources of instruction. Yet it is a single picture which we build, a unified structure, in which we ourselves have a place, and in which every element is thought of as directly or indirectly related to every other; and the framework of the structure, the common, unifying system of relations is spatio-temporal. By means of identifying references, we fit other people's reports and stories, along with our own, into the single story about empirical reality; and this fitting together, this connexion, rests ultimately on relating the particulars which figure in the stories in the single spatiotemporal system which we ourselves occupy.
We might now ask whether it is inevitable, or necessary, that any scheme which provides for particulars capable of being the subject-matter of discourse in a common language -- or at least any such scheme as we can envisage -- should be a scheme of the kind I have just described. Certainly it does not seem to be a contingent matter about empirical reality that it forms a single spatio-temporal system. Suppose someone told of a thing of a certain kind, and of certain things that had happened to it; and, when asked where that thing had been, and when the events he recounted had occurred, said, not that he did not know, but that they did not belong at all to our spatio-temporal system, that they did not take place at any distance from here or at any distance of time from now. Then we should say, and take him to be saying, that the events in question had not really occurred, that the thing in question did not really exist. In saying this, we should show how we operate with the concept of reality. But this is not to say that our concept might not have been different, had the nature of our experience been fundamentally different. Later I shall explore some ways in which it might have been different; and there are others which I shall not explore. We are dealing here with something that conditions our whole way of talking and thinking, and it is for this reason that we feel it to be non-contingent. But this fact need not prevent us from undertaking a deeper analysis of the
concept of a particular, and considering, though at no small risk of absurdity, quite different possibilities.
For the time being I shall leave aside such possibilities, and raise, instead, questions about our own conceptual scheme. There are questions enough to be raised. But it is worth first reemphasizing the illusoriness of certain difficulties. There is, for example, the belief which we made our starting-point, the belief that however elaborate a description we produce of a network of spatially and temporally related things and incidents, we can never be sure of producing an individuating description of a single particular item, for we can never rule out the possibility of another exactly similar network. To experience this theoretical anxiety is, as we have seen, to overlook the fact that we, the speakers, the users of the dating and placing systems, have our own place in that system and know that place; that we ourselves, therefore, and our own immediate environment, provide a point of reference which individuates the network and hence helps to individuate the particulars located in the network. A different, but not unrelated, error is made by those who, very well aware that here-and-now provides a point of reference, yet suppose that 'here' and 'now' and 'this' and all such utterance-centred words refer to something private and personal to each individual user of them. They see how for each person at any moment there is on this basis a single spatio-temporal network; but see also that, on this basis, there are as many networks, as many worlds, as there are persons. Such philosophers deprive themselves of a public point of reference by making the point of reference private. They are unable to admit that we are in the system because they think that the system is within us; or, rather, that each has his own system within him. This is not to say that the schemes they construct may not help us to understand our own. But it is with our own that we are concerned. So we shall not give up the platitude that 'here' and 'now' and 'this' and 'I' and 'you' are words of our common language, which each can use to indicate, or help to indicate, to another, who is with him, what he is talking about.
 We operate with the scheme of a single, unified spatiotemporal system. The system is unified in this sense. Of things of which it makes sense to inquire about the spatial position, we think it always significant not only to ask how any two such things are spatially related at any one time, the same for each, but also to inquire about the spatial relations of any one thing at any moment of its history to any other thing at any moment of its history, when the moments may be different. Thus we say: A is now in just the place where B was a thousand years ago. We have, then, the idea of a system of elements every one of which can be both spatially and temporally related to every other.
Let us consider, first, some conditions, and then some consequences, of our possession and use of this scheme. One of the conditions of our use of this scheme is that we should be able to identify particulars in a sense, or application, of the word 'identify' different from that which I have so far considered. If a man in my presence, refers to a copy of a book which he has in his hand, I may, in the application of the word we have so far considered, identify the particular he is referring to: it is the book in his hand. But in another application of the word I may fail to identify that particular. I may think I have never seen it before, when it is in fact my own copy. I fail to identify it as, say, the copy I bought yesterday.
Now if we are to operate the scheme of a single unified spatiotemporal system or framework of particulars, it is essential that we should be able sometimes to identify particulars in the way I have just illustrated. More generally, we must have criteria or methods of identifying a particular encountered on one occasion, or described in respect of one occasion, as the same individual as a particular encountered on another occasion, or described in respect of another occasion. For the sake of terminological clarity we may, when necessary, distinguish between referential, or speaker-hearer, identification on the one hand, and reidentification on the other. It is not surprising that it should be natural to use the word 'identify' in both connexions. In both kinds of case, identifying involves thinking that something is the same:
that the particular copy I see in the speaker's hand is the same particular as that to which he is referring; that the copy in his hand is the same particular as the copy I bought yesterday.
Why are criteria of reidentification necessary to our operating the scheme of a single unified spatio-temporal framework for referential identification? The necessity may be brought out in the following way. It is not the only way. Evidently we can sometimes referentially identify a member of the spatio-temporal framework by giving, or being given, its position relative to others. No less evidently we cannot make the identification of every element in the system in this way relative to that of other elements. An immediate answer is that we have no need to, because we can identify some elements by direct location. But this answer, by itself, is insufficient. For we do not use a different scheme, a different framework, on each occasion. It is the essence of the matter that we use the same framework on different occasions. We must not only identify some elements in a non-relative way, we must identify them as just the elements they are of a single continuously usable system of elements. For the occasions of reference themselves have different places in the single system of reference. We cannot attach one occasion to another unless, from occasion to occasion, we can reidentify elements common to different occasions.
Our methods, or criteria, of reidentification must allow for such facts as these: that the field of our observation is limited; that we go to sleep; that we move. That is to say, they must allow for the facts that we cannot at any moment observe the whole of the spatial framework we use, that there is no part of it that we can observe continuously, and that we ourselves do not occupy a fixed position within it. These facts have, among other consequences, this one: that there can be no question of continuous and comprehensive attention to the preservation or change of spatial boundaries and the preservation or continuous change of spatial relations on the part of things mostly undergoing no, or only gradual, qualitative change. Perhaps some philosophers of a Hume-like turn of mind have felt that only by this impossible method could we be sure of the continued identity
of physical things; that in its absence identity was something feigned or illusory or at best doubtful. The conclusion, like all philosophically sceptical conclusions, is necessarily avoidable. But the fact from which it has seemed to follow is important. Whatever our account may be, it must allow for discontinuities and limits of observation. So it must lean heavily on what we may for the moment call 'qualitative recurrences' -- that is to say, on the fact of repeated observational encounters with the same patterns or arrangements of objects -- where, for the moment, we allow to this phrase 'same patterns or arrangements of objects' all the ambiguity, as between qualitative and numerical (or particular) identity, that it confusingly, but also helpfully, has. But now it might seem that if we do in fact lean thus heavily on such recurrences, then either we are driven to scepticism about particular-identity or the whole distinction between qualitative and numerical identity comes into question, except when it applies to what falls within the field of an uninterrupted stretch of observation. What I mean by the whole distinction coming into question is something like this. When we say 'the same' of what does fall within the field of an uninterrupted stretch of observation, we can clearly distinguish between the cases where we mean to speak of qualitative identity and the cases where we mean to speak of numerical identity.
If, for instance, we say:
The figure in the top-left-hand corner of this diagram is the same as the figure which has a parallellogram to the right of it and a circle beneath it,
we use 'the same' to speak of numerical identity; whereas if we say:
The figure in the top-left-hand corner of the diagram is the same as the figure in the bottom-right-hand corner of the diagram,
we have a simple case of using 'the same' to speak of qualitative identity. Where we say 'the same' of what is not continuously observed, we think we can as clearly make just this same distinction. But can we? Since spatio-temporally continuous existence is, by hypothesis, observed neither in the case where we are inclined to speak of qualitative identity nor in the case where we are inclined to speak of numerical identity, by what right do we suppose that there is a fundamental difference between these cases, or that there is just the difference in question? There are differences, certainly; but they are just differences in the ways in which observation-situations or scenes resemble and differ from one another; or in the ways in which certain features of observation-situations or scenes resemble one another and differ from one another. To take a Hume-like position, we might say: these differences suggest to us an unobserved continuity in one set of cases and its absence in another set, make us perhaps imagine this; and thus we are led to confuse these differences with the difference between numerical and qualitative identity. But really all we have, in the case of non-continuous observation, is different kinds of qualitative identity. If we ever mean more than this in talking of identity, in cases of non-continuous observation, then we cannot be sure of identity; if we can be sure of identity, then we cannot mean more than this.
But now we see we are just in one of the characteristic situations of philosophical scepticism: which allows us the alternatives of meaning something different from what we do mean, or of being for ever unsure; because the standard for being sure while meaning what we do mean is set self-contradictorily high, viz, having continuous observation where we have non-continuous observation. So the complaint that you cannot be sure reduces to the tautology that you do not continuously observe what you do not continuously observe.
But the point can be better put another way. There is no doubt that we have the idea of a single spatio-temporal system of material things; the idea of every material thing at any time being spatially related, in various ways at various times, to every other at every time. There is no doubt at all that this is our conceptual scheme. Now I say that a condition of our having this conceptual scheme is the unquestioning acceptance of particular-identity in at least some cases of non-continuous observation. Let us suppose for a moment that we were never willing to ascribe particular-identity in such cases. Then we should, as it were, have the idea of a new, a different, spatial system for each new continuous stretch of observation. (Most of the common concepts of material things that we have would not exist; for the continuous stretches of observation that do occur are not long enough or comprehensive enough to allow of any use for them.) Each new system would be wholly independent of every other. There would be no question of doubt about the identity of an item in one system with an item in another. For such a doubt makes sense only if the two systems are not independent, if they are parts, in some way related, of a single system which includes them both. But the condition of having such a system is precisely the condition that there should be satisfiable and commonly satisfied criteria for the identity of at least some items in one sub-system with some items in the other. This gives us a more profound characterization of the sceptic's position. He pretends to accept a conceptual scheme, but at the same time quietly rejects one of the conditions of its employment. Thus his doubts are unreal, not simply because they are logically irresoluble doubts, but because they amount to the rejection of the whole conceptual scheme within which alone such doubts make sense. So, naturally enough, the alternative to doubt which he offers us is the suggestion that we do not really, or should not really, have the conceptual scheme that we do have; that we do not really, or should not really, mean what we think we mean, what we do mean. But this alternative is absurd. For the whole process of reasoning only starts because the scheme is as it is; and we cannot change it even if we would. Finally, we may, if we choose, see the sceptic as offering for contemplation
the sketch of an alternative scheme; and this is to see him as a revisionary metaphysician with whom we do not wish to quarrel, but whom we do not need to follow.
There are a hundred complications about the idea of a stretch of continuous observation, about what would count as such a stretch. To go into these fully we should have to consider many facts and questions: ranging from questions about the special position of our own bodies, and about the relations between sight and touch, to simple facts like the fact that we cannot look in all directions at once. But I am not now concerned with these complications, though to some of these questions -- e.g. that of the special position of one's own body -- I shall have to return later.
 There is, however, one complication of a quite different kind which I must mention now. The description which I gave of the condition of our having the scheme we do have -- the scheme of a single spatio-temporal system of physical things -- is in a certain respect incomplete. It is not enough that we should be able to say 'the same thing'; we must also be able to say 'the same place'. For suppose I encounter a thing x at a time t and reidentify x at a later time t'. Then, it appears, the fact that I know the spatial relations which an objecty stood to x at t, and the spatial relations in which an object z stands to x at t' does not mean that I know anything at all about the spatial relations between y and z. Yet if we are to operate the scheme of a single spatio-temporal framework there must be an answerable question of the form: What are the spatial relations between y at t and z at t'?; or, more perspicuously: What, in relation to the spatial position of z at t', was the spatial position of y at t? And if I cannot answer this question on the strength of knowing the spatial relations of y at t and of z at t' to one and the same thing, namely x, how can I answer it at all? To be able to answer such questions, I must be able to reidentify not only things, but places.
Yet this is a misleading way to bring out the incompleteness of the account I gave. For the reidentification of places is not something quite different from, and independent of, the reidentification
of things. There is, rather, a complex and intricate interplay between the two. For on the one hand places are defined only by the relations of things; and, on the other, one of the requirements for the identity of a material thing is that its existence, as well as being continuous in time, should be continuous in space. That is to say, for many kinds of thing, it counts against saying that a thing, x, at one place at one time is the same as a thing, y, at another place at another time, if we think there is not some continuous set of places between these two places such that x was at each successive member of this set of places at successive times between these two times and y was at the same member of the set of places at the same time.
So the identification and distinction of places turn on the identification and distinction of things; and the identification and distinction of things turn, in part, on the identification and distinction of places. There is no mystery about this mutual dependence. To exhibit its detail is simply to describe the criteria by which we criticize, amend and extend our ascription of identity to things and places. I shall not try to exhibit its detail in full. I shall just describe one side of this dependence. If we encounter a set of things which we are prepared to call the same as a previously encountered set, and if the relative spatial positions of these things are unchanged, then, so long as we confine our remarks within the limits of that set of things, we say that each member of the set is in the same place as it was before. If some, but not all, members of such a set have changed their relative positions, then we may say of some that they are in different places and of some that they are in the same place. Of which we shall say which, depends on our selection of certain members of the set as constituting a dominant framework for the set as a whole. This selection need in no way depend, though it may depend, on our surreptitiously thinking outside the limits of the set. On the whole, we shall select those elements of the set, if any, which can be thought of as containing or supporting the remainder, or on which the set can be thought of as centred. We do not change these criteria, but merely enlarge their application, when we consider the place of the set itself, or of things in it, in relation to other things or sets of things. It is
easy to see how, consequently, we can construct antinomies, if we choose, by varying the frame of reference in which we ask of one thing the question: Is it in the same place? My hat is in the same place as it was; for it is still on the back seat of the car. But it is in a different place; for the car has travelled from London to Manchester. But these antinomies should perplex no one. They certainly do not count against the principle that we employ the scheme of a single unified spatio-temporal system for the things we talk about. They show merely how, in different contexts of discussion, we may narrow or broaden the range of our talk. The grip of the principle on our discourse about particulars is never abandoned; but it is not so tight as to inhibit shifts in the frames of reference of our spatial talk.
3. BASIC PARTICULARS
 We can make it clear to each other what or which particular things our discourse is about because we can fit together each other's reports and stories into a single picture of the world; and the framework of that picture is a unitary spatio-temporal framework, of one temporal and three spatial dimensions. Hence, as things are, particular-identification in general rests ultimately on the possibility of locating the particular things we speak of in a single unified spatio-temporal system. Many qualifications are covered by the word 'ultimately'. We can, for example, be arguing about the same man, though we disagree about his dates. We can speak of the same thing, though we disagree about its position in space at different times. But such disagreements are possible only in a context of larger, if looser, agreement about the relations of these entities to others about which we do not disagree.
The question I want now to ask is one already foreshadowed. Given the general character of the conceptual scheme I have described, is there any one distinguishable class or category of particulars which must be basic from the point of view of particular-identification? This question resolves itself into two. First, is there a class or category of particulars such that, as things are, it would not be possible to make all the identifying references which we do make to particulars of other classes, unless we made
identifying references to particulars of that class, whereas it would be possible to make all the identifying references we do make to particulars of that class without making identifying reference to particulars of other classes? Second, can we argue to an affirmative answer to this question from the general character of the conceptual scheme I have described?
It seems that we can construct an argument from the premise that identification rests ultimately on location in a unitary spatiotemporal framework of four dimensions, to the conclusion that a certain class of particulars is basic in the sense I have explained. For that framework is not something extraneous to the objects in reality of which we speak. If we ask what constitutes the framework, we must look to those objects themselves, or some among them: But not every category of particular objects which we recognize is competent to constitute such a framework. The only objects which can constitute it are those which can confer upon it its own fundamental characteristics. That is to say, they must be three-dimensional objects with some endurance through time. They must also be accessible to such means of observation as we have; and, since those means are strictly limited in power, they must collectively have enough diversity, richness, stability and endurance to make possible and natural just that conception of a single unitary framework which we possess. Of the categories of objects which we recognize, only those satisfy these requirements which are, or possess, material bodies -- in a broad sense of the expression. Material bodies constitute the framework. Hence, given a certain general feature of the conceptual scheme we possess, and given the character of the available major categories, things which are, or possess, material bodies must be the basic particulars.
I shall have more to say later about this qualifying phrase 'given the character of the available major categories'. But one point I shall mention now. We might regard it as a necessary condition of something being a material body, that it should tend to exhibit some felt resistance to touch; or, perhaps more generally, that it should possess some qualities of the tactual range. If we do, then this is a more stringent requirement than any that Descartes intended by 'extension' or Locke by 'solidity'; that is
to say, it is a more stringent requirement than that of the three-dimensional occupation of space. For this latter requirement, which is what the argument seems to lead to, might be satisfied empirically, it seems, by purely visual occupiers-of-space. (It is in fact satisfied for the blind by purely tactual occupiers-of-space.) In practice, not many purely visual occupiers-of-space are to be found: some cases that might be suggested, such as ghosts, are altogether questionable; others, such as shafts of light or volumes of coloured gas, certainly do not satisfy the requirements of richness, endurance and stability. But in so far as they are to be found, we do hesitate to call them material bodies. So it appears that there exists the theoretical possibility that the requirements of the argument might be met by a category of entities which we should not call material bodies; though, as things are, these requirements are met only by what we are ready to call material bodies. The theoretical possibility, if it is one, seems of only moderate interest, and I shall refrain from exploring it. In any case we can satisfy ourselves formally, by introducing a weak sense of 'material body' for which the supposed purely visual three-dimensional objects are allowed to qualify; and then re-state the conclusion of the argument more simply as follows. Given a certain general feature of the conceptual scheme of particular-identification which we have, it follows that material bodies must be the basic particulars.
The form of this argument might possibly mislead. It is not that on the one hand we have a conceptual scheme which presents us with a certain problem of particular-identification; while on the other hand there exist material objects in sufficient richness and strength to make possible the solution of such problems. It is only because the solution is possible that the problem exists. So with all transcendental arguments.
 To rest any philosophical position on an argument so general and so vague would be undesirable. But there is no need to do so. We can inquire more directly and in greater detail whether there is reason to suppose that identification of particulars belonging to some categories is in fact dependent on identification
of particulars belonging to others, and whether there is any category of particulars which is basic in this respect.
I remarked earlier that speaker and hearer often identify one particular by reference to another; that is to say, that often an identifying reference to one particular, when supplemented, if necessary, from the linguistic context, contains a mention of another particular; and that a hearer's successful identification of the first may then depend on his successful identification of the second. The clearest possible case of general identifiability-dependence of one type of particular on another would be the case in which it was impossible to identify a particular of one type without this kind of dependence on the identification of a particular of the other type. Perhaps there are no pure cases of such direct identifiability-dependence. But there is at least one very important case which approximates to being of this kind. That is to say, there are two important general types or categories of particular, the identification of the members of one of which is, in almost this way, dependent on the identification of members of the other. The dependent type is the class of what might be called 'private particulars' -- comprising the perhaps overlapping groups of sensations, mental events and, in one common acceptance of this term, sense-data. The type on which it is dependent is the class of persons. (Perhaps we should add 'or animals'; for perhaps we sometimes refer identifyingly to the particular experiences of animals. But this is a complication I shall neglect.) On other criteria than the present, private experiences have often been the most favoured candidates for the status of 'basic' particulars; on the present criteria, they are the most obviously inadmissible. The principles of individuation of such experiences essentially turn on the identities of the persons to whose histories they belong. A twinge of toothache or a private impression of red cannot in general be identified in our common language except as the twinge which such-and-such an identified person suffered or is suffering, the impression which such-and-such an identified person had or is having. Identifying references to 'private particulars' depend on identifying references to particulars of another type altogether, namely persons.
There might seem to be an obvious objection to this view. If someone is writhing on the ground and says. "This (the) pain is terrible', has he not made an identifying reference to a private particular, viz, his sensation of pain, without mentioning or referring to the person who is suffering the pain, viz, himself? Certainly there need be no linguistic context, involving reference to another particular, with which the hearer need supplement the reference in order to identify the particular concerned. He identifies it straight away as the pain that the speaker is suffering. Similarly a doctor may apply a pressure to a patient and then ask: 'How severe was that pain?' and the patient will successfully identify the pain the doctor refers to as that which he, the hearer, has just suffered or is suffering. In these cases, however, it may fairly be said of the demonstrative phrases that they really do have the function which is sometimes mistakenly said to be always theirs. That is to say, they really do contain an implicit reference to a particular person; they really are a kind of shorthand for 'the pain I am suffering', in the first example, or 'the pain you have just suffered', in the second. If it is asked why a similar thing is not true of any identifying demonstrative phrase referring to a public object, e.g. why 'This tree' is not short for 'The tree you (I) can see over there', the answer is as follows. The demonstrative identifying phrase, 'This tree', used of a particular tree, may be spoken to anybody by anybody, in the appropriate surroundings, without change of identificatory force. No implicit reference to a particular person is essential to its identificatory force; all that is essential is that the surroundings and context are such that the reference is clearly to a particular tree. The implicit reference to a particular person is, however, essential to the identificatory force of demonstrative phrases referring to private experiences. This constitutes a sufficient reason for distinguishing the two types of case in the way I have suggested, and hence for maintaining that the apparent exception is not a real one.
Another way of putting the point, which may later have certain advantages, is as follows. We may admit, if we like, that an implicit reference to speaker and hearer is involved in any demonstrative identifying reference made in the presence of the object
referred to; and then say that this implicit reference to persons, being absolutely general in such situations, is to be discounted in the context of the present discussion, so long as it is simply a consequence of the fact that the persons concerned are respectively speaker and hearer. Now the implicit reference to a person in the case we are concerned with -- the case of a private experience -- is not simply a consequence of this fact, but also of the fact that he is the person whose private experience we are referring to. That this is so may be seen clearly from the case in which A says to B, apropos the manifestly suffering C, in whose presence they are, 'The pain must be acute'. The implicit reference to C is here quite independent of his having the role of speaker or hearer; for he does not have either role.
Why then did I qualify my initial statement of the relation of identifiability-dependence between 'private' particulars and persons? I qualified it for the following reason. It would be possible for an experience to be identified as the one experience of a certain kind suffered in a certain identified place at a certain time; it would be possible for someone to be authoritatively told that such a description had application, and hence to identify the experience when it was referred to, without any independent knowledge of the identity of the sufferer of the experience. This, then, would be a case in which the most direct relation of identifiability-dependence between experiences and persons did not hold. The qualification which such a possibility necessitates, however, is not very important or far-reaching. For it could be known that such an identifying description had applicatien only under certain conditions. It would be necessary, in order for the experience-description to be given currency, that someone or other, who gave it currency, should also have been able to give an independent identification of the sufferer of the experience. So even though, on a particular occasion of reference, the identification of a private experience need not be directly dependent on the identification of the person whose experience it was, it must still be indirectly so dependent.
With this qualification, which is in practice of small importance, we may say, then, that private particulars exhibit the most direct
kind of identifiability-dependence on particulars of another type. In extreme contrast with the class of private experiences lies another, though less well-defined, class of particulars, which suffers equally obviously from identifiability-dependence. This is the class of particulars which might be called 'theoretical constructs'. Certain particles of physics might provide one set of examples. These are not in any sense private objects; but they are unobservable objects. We must regard it as in principle possible to make identifying references to such particulars, if not individually, at least in groups or collections; otherwise they forfeit their status as admitted particulars. Perhaps we do not often make such references in fact. These items play a role of their own in our intellectual economy, which it is not my concern to describe. But it is clear enough that in so far as we do make identifying references to particulars of this sort, we must ultimately identify them, or groups of them, by identifying reference to those grosser, observable bodies of which perhaps, like Locke, we think of them as the minute, unobservable constituents.
Particles of physics are one kind of example of particulars of this class. I mentioned them first, because, like private experiences, they exhibit the most direct kind of identifiability-dependence. There are many others which need exhibit no more than a general identifiability-dependence. I spoke of the class as ill-defined; and clearly it is, so far, no better defined than the extremely vague concept of observability. We speak of a particular political situation or economic depression. We may even speak of observing such phenomena. But it would be clearly vain to hope to find basic particulars among such items as these. The possession of the concepts under which such particulars fall all too evidently presupposes the possession of other concepts under which fall particulars of wholly different and far less sophisticated types. We could not, for example, have the concept of a strike or a lockout unless we had such concepts as those of men, tools and factories. From this there follows immediately a general identifiability-dependence of particulars of the more sophisticated, upon particulars of the less sophisticated, type. For we could not speak of, and hence, identify, particulars of the more sophisticated type
unless we could speak of, and hence identify, particulars of the less sophisticated type. This does not mean that on any particular occasion of reference we must mediate an identifying reference to a particular of a more sophisticated type by an identifying reference to a particular of a less sophisticated type. We might refer quite directly, for example, to 'the present economic depression'.
If, then, there are any basic particulars in the sense I have indicated, it seems that the sense in which they must be observable is not merely this: that it should be correct to speak of observing them. It seems likely, rather, that they must be public objects of perception, particular objects of such kinds that different people can quite literally see or hear or feel by contact or taste or smell the same objects of these kinds. They must, it seems, be objects belonging to kinds such that objects of these kinds can be directly located by both hearer and speaker on some particular occasions of discourse. Nevertheless, I shall construe the limits of the class of the publicly observable fairly liberally. The more liberally these limits are construed, the less is my dependence on the argument from presupposition of concepts. It is desirable to reduce dependence on this aigument as much as possible. Its application would be a matter of detail and dispute; and its explanatory power is small. We shall return later to consider further a more exact form of the argument.
Now it is evident that any item which can be directly located, can to that extent be identified without a mediating reference to any other particular at all, and hence without reference to any particular of a type or category other than its own. But, of course, it does not follow from this that the category to which such an item belongs is a category of basic particulars. For the range of actual particular items directly locatable on any particular occasion of discourse is severely restricted; and it may well be that the identifiability on a particular occasion of some items which lie outside that range is dependent on the identifiability of other items of different types or categories from theirs. The fact that an item falls within the general class of the publicly perceptible does not, therefore, preclude its belonging to some category which
suffers from identifiability-dependence on some other category also falling within the general class of the publicly perceptible.
But how shall we divide publicly perceptible, or publicly observable, particulars into types or categories? Clearly there are many ways of doing so, adapted to different philosophical purposes. I shall be content with the roughest of divisions. I shall speak, for example, of events and processes, states and conditions on the one hand; and of material bodies or things possessing material bodies, on the other. I shall use these terms loosely: for example, a field or a river will count as material bodies or things possessing material bodies. In general, I shall not claim that my distinctions are very clear, or that they are precise or exhaustive. They may nevertheless serve my purpose. Another distinction, worth mentioning now, to which I shall later refer is that between, e.g. events and processes which, as named and conceived of by us, necessarily are of, or performed or undergone by, material bodies or things possessing material bodies, and events and processes not of this kind. Thus a death is necessarily the death of some creature. But that a flash or a bang occurred does not entail that anything flashed or banged. 'Let there be light' does not mean 'Let something shine'.
We have already seen that it is quite possible, in certain circumstances, to identify, e.g., events and processes without any dependence on identification of particulars of other types. For public events and processes may he directly locatable. Such expressions as 'That flash', uttered immediately after there has been a flash, 'That terrible noise', uttered while the noise continues, enable the hearer directly to locate the particular in question. They involve no reference to any other particular at all, except at most for the discountable implicit references to hearer and speaker which have already been discussed, and a fortiori no reference to particulars of other types. This is surely not the only case in which such a particular can be identified without reference to particulars of other types. Suppose, for example, all the flashes and bangs that occurred could be ordered in a single temporal series. Then, in principle, every member of the series could be identified without reference to anything that was not a member of the series: it could
be identified, say, as the bang that immediately preceded the nth flash before the last. Now, on occasion, we can work with the idea of a partial sequence, or series, of a somewhat similar kind. We can work with it, for example, in the case of what I shall call a directly locatable sequence. This concept is to be understood as relative in its application to a time, and to a speaker-hearer pair. Thus a directly locatable sequence of bangs for a speaker-hearer pair at a certain time would be a series of bangs which was going on at that time, or had just ceased at that time, and all the members of which were audible to both members of the pair. So long as the range of reference was understood as restricted within the limits of the series, every member of the series could be identified, on the model indicated above, without reference to any particular of a type other than its own.
But of course not all flashes and bangs that may be identifyingly referred to are, on the occasion of the reference, members of a directly locatable sequence for those who refer to them. Nor is there any other kind of humanly constructible flash-bang sequence, with the two properties (1) that at least one member of such a sequence can always be identified directly, i.e. without reference to any other particular at all, and (2) that every reference to any other such particular can identify it solely by its position relative to that of other members of such a sequence. Perhaps this is merely a contingent limitation of the human condition. If so, it is a limitation which determines the nature of our identifying reference to flashes and bangs. In practice, when we wish to refer identifyingly to a particular phenomenon of this kind, and are not in the artificially favourable position of being able to do so by placing it in a directly locatable sequence, we do so by way of a reference, usually implicit in the linguistic context, to a particular of some quite different sort; for example, to a place at which it was audible or visible, or to a particular material object which was causally connected with it. In practice, that is to say, there are other dimensions of identification involved besides the simple one of temporal position within a single determinable series of roughly homogeneous particulars.
The point may be made clearer by considering one or two
moderately convincing instances of humanly constructible series of particular states or processes, such that there are no particulars of the kind concerned which are not members of this single series, and such that one member of the series can always be directly identified. The sequence of nights and days, considered simply as alternating periods of prolonged and general light or darkness, is one example, and the sequence of years, regarded simply as seasonal cycles, another. This must be understood with certain qualifications: for instance, we must ignore the confusing consequences of going round the world. With these reservations, we may say that since there are no nights and days, or seasonal cycles, which are not members of such a single series, any particular member can be identified as the nth before, or after, the present one. It is no accident that our dating system makes use of such convenient phenomena.
If we inquire about the underlying reasons for this difference between the two types of phenomena, a part, though only a part, of the answer is this. The members of the night-day sequence are relatively general, in the sense of generally discriminable, throughout the areas of space we are concerned with. (Here again certain obvious reservations are to be made.) But this is by no means true of the members of any hypothetical flash-bang sequence that we may dream of. The day that dawns in Scotland dawns in England too. But the bang made by an exploding tyre in London is not audible in Edinburgh.
Apart from such special, and dubious, cases as the night-day sequence, what I have said of the jejune example of flashes and bangs holds for other publicly observable events and processes, states and conditions. This, I think, is true, however liberally we construe the concept of a humanly constructible identification-series, of which the members are to be only particulars of these types, and of which at least one member is always to be identifiable without reference to any other particular at all. Thus we might, perhaps, allow a series of battles to constitute such a series for two generals now engaged in a particular war; a series of viva-voce examinations to constitute another for the examiners conducting them. Then any particular battle, or any particular
viva-voce examination within the series, could be identified by means of its position in the series. Further, we must allow, in principle, for the construction of complex series, series of heterogeneous events or processes, in which identifying references would take such a form as 'The first j before the last y before the second c before the last'. But obviously this method of identifying events, processes or states, while avoiding reference to particulars of other types than these, suffers in general from severe practical limitations of the kind we have already encountered. Except in such special cases as that of a directly locatable sequence, there is no reason to suppose that any such series which any one person was able to make use of for identificatory purposes would be identical with any similar series which any other person was able to make use of for these purposes. It is useless to appeal to such a theoretical notion as that of the complete series of events of one specific kind, e.g. of deaths. For it is obvious that no one who wishes to refer to a particular death could know its position in that series. Again, this is perhaps a contingent matter; but one that radically conditions the nature of identifying reference.
It might appear that in concentrating on what could be seen as contingent limitations of human powers, I have neglected to use two powerful theoretical arguments against the general possibility of identifying events, processes, states and conditions by the method described, without reference to particulars of other types. The first argument is that this method of identifying events &c. provides no means of distinguishing simultaneous similar events in any given series; since they are always identified by their position in a temporal order only. But this is easily answered. For there is no logical reason why the relations exploited in the construction of such a series should be those of temporal order alone. For instance, we often say that one event was the cause of another; and clearly, of two simultaneous events of the same specific kind, one will indeed have causal antecedents and consequences which the other lacks. Nor does the fact that reference is restricted to, say, events and processes, preclude the use of spatial discriminations. If we consider again the favourable case of a directly locatable sequence, it may be perfectly possible to distinguish between
simultaneous similar members of such a sequence by means of their spatial relations, without reference to particulars of other types. Imagine, for example, a series of moves in chess, which in fact constitute two distinct games played by two distinct pairs of players: but the moves in each game are identical and simultaneous. Nevertheless a watching speaker and hearer can distinguish between the two streams of moves as, say, the left-hand and the right-hand stream, and hence can refer identifyingly to the last move but one in the left-hand stream. The objection, therefore, is not decisive. But it is not without value. For it serves to emphasize once again the severe practical limitations of the method.
The other theoretical argument which I might seem to have neglected is this. It is true of a significant, perhaps of a preponderant, proportion of the kinds of events, processes, states or conditions for which we have names, that these events or processes are necessarily the actions or undergoings of things which are not themselves processes, states or events; that these states or conditions are necessarily states or conditions of things which are not themselves states, conditions, processes or events. It might be thought that from this fact alone it could be argued directly that the identification of most events, states or processes must proceed via the identification of those particulars of other types to the history of which they belonged; that e.g. where a particular event was of a kind such that all events of this kind necessarily happen to things of another type, then the identification of the particular event necessarily involved the identification of the particular thing to which it happened. Thus no particular death could be identifyingly referred to without an at least implicit identifying reference to the creature whose death it was; for all deaths are necessarily deaths of creatures. For someone directly to locate a death, he would have directly to locate the creature whose death it was. Thus 'This death', when used as a true demonstrative identifying reference, i.e. in the presence of the death concerned, would have the force of 'The death of this creature'.
This argument is unsatisfactory as it stands. For it is simply untrue that we cannot refer identifyingly to an observable event of a kind such that the occurrence of events of that kind entails the
existence of particulars of a different type, without dependence upon an implicit identifying reference to some particular of that type. My identifying reference to a scream need in no way depend, for its idcntificatory force, on an implicit identifying reference to the screamer. The original argument errs in trying to infer from a conceptual dependence too direct a kind of identifiability-dependence of particulars.
The argument may, however, be replaced by one with a weaker conclusion. Suppose that b s are necessarily b s of a s (e.g. that births are necessarily births of animals). Then, though on a particular occasion I may identify a particular b without identifying the a it is of, yet it would not in general be possible to identify bs unless it were in general possible to identify as. For we could not speak of bs as we do speak of them, or have the concept we do have of bs, unless we spoke of as; and we could not speak of as unless it were in principle possible to identify an a. So, in a general sense, bs show identifiability-dependence on as.
But now the amended argument seems to prove too much. For if we say that having the concept we do have of a birth entails having the concept we do have of an animal, on the ground that This is a birth entails There is some animal of which this is the birth, we must, it seems, also say that having the concept we do have of an animal entails having the concept we do have of a birth; for This is an animal entails There is some birth which is the birth of this animal. Whence, by parity of reasoning, the argument shows a mutual identifiability-dependence between births and animals. And so the argument is useless to us. For we are interested only in non-symmetrical relations of dependence.
Nevertheless, I think the amended argument can be restated so as to avoid this consequence. For there is after all a certain asymmetry in the relations between the concept of an animal and the concept of a birth. It is true that This is an animal entails There is some birth which is the birth of this. But this entailment admits of the following paraphrase: This is an animal entails This was born. Now while it may seem reasonable to maintain that our concept of an animal would be different if we could not express the entailment in the second form, it also seems reasonable to deny that our concept
of an animal would be different if we merely lacked a means of expressing the entailment in its first form. In other words, it can reasonably be maintained that in order to speak of animals with the sense which this word in fact has for us; we must find a place in our discourse for the concept being born; but there is no reason to conclude from the fact that we speak of animals with the sense this word has for us, that we must also find a place in our discourse for the idea of a certain range of particulars, viz, births. Whether we also do this or not is irrelevant to our having the concept of an animal that we do have. Here there is a real asymmetry. For there is no corresponding paraphrase of the entailment from This is a birth to There is an animal of which this is the birth. We can paraphrase one entailment so as to eliminate what logicians might call quantification over births; but we cannot paraphrase the other so as to eliminate quantification over animals. In other words, the admission into our discourse of the range of particulars, births, conceived of as we conceive of them, does require the admission into our discourse of the range of particulars, animals; but the admission into our discourse of the range of particulars, animals, conceived of as we conceive of them, does not require the admission into our discourse of the range of particulars, births.
As finally amended, the argument, I think, is sound. A large class of particular states and conditions, events and processes, are conceived of as necessarily states and conditions of, or as performed or suffered by, particulars of other types, notably things which are or have material bodies. The argument establishes a general and one-way identifiability-dependence of the former class of particulars on the latter, given just the concepts that we have. The reason why it is desirable to rest as little weight as possible upon the argument is that, though it is sound, it has, as I have already suggested, little or no explanatory power. The argument does not explain the existence of the general identifiability-dependence it establishes. It remains a question why particulars which figure in our conceptual scheme should exhibit the relation on which the argument draws, why we should conceive of the relevant particulars just in these ways.
Let us return, then, to those already noticed general limitations to which events, processes, states and conditions are subject as candidates for identification without reference to other types of thing. To summarize what I have said about these limitations. The minimum conditions of independent identifiability for a type of particulars were that its members should be neither private nor unobservable. Many kinds of state, process, event or condition satisfy these two conditions. In suitable circumstances such a particular can be directly located and thus identified without reference to any other particular at all. Even when not directly locatable, such a particular may be identified without any reference, explicit or implicit, to any particular which is not itself a state, process, event or condition, as the case may be. But the cases in which this intra-typical identification is possible are severely restricted. For they require that the parties to an identifying reference should be operating with one and the same type-homogeneous referential framework. And the fundamental limitations of states, processes, events and conditions, as in dependently identifiable particulars, is their failure to supply frameworks of this kind which are at all adequate to our referring needs. Still less can they supply, of themselves, a single, comprehensive and continuously usable framework of this kind. So we enormously extend the range of our possible identifying references to states, processes & c. by allowing them to be mediated by reference to places, persons and material things.
Now, in the respects just mentioned, material bodies appear to be much better candidates for the status of basic particulars than any we have so far considered. They supply both literally and figuratively, both in the short and in the long term, both widely and narrowly, our physical geography, the features we note on our maps. They include, that is to say, a sufficiency of relatively enduring objects (e.g. geographical features, buildings &c.) maintaining with each other relatively fixed or regularly changing spatial relations. Here 'sufficient' and 'relative' refer to our human situation and needs. When we were considering states, processes &c., we noted that there was no rich complexity of time-taking things which were generally discriminable and
similarly related throughout the areas of space we are concerned with. But there is a rich complexity of space-taking things which are relatively enduring and similarly related throughout the tracts of time we are concerned with. Material bodies, in a broad sense of the word, secure to us one single common and continuously extendable framework of reference, any constituent of which can be identifyingly referred to without reference to any particular of any other type. This is the framework for spatial location in general. The detailed constitution of this framework changes; but without detriment to its unity. Knowledge of the detail of its composition varies from one person to another; but without detriment to its identity. Of course not all material bodies, or things which have them, are regarded as even transient parts of such a framework: many bodies are too much in movement, or too ephemeral, or both. One would not, so to speak, use them in giving spatial directions unless they were then and there observable. But that does not preclude their identification, when necessary, by reference, first, to each other, and ultimately, to constituent elements of the framework. If we take as a sufficient condition of type-homogeneity, for these purposes, the being or possessing a material body, we may venture to think that all things which satisfy this condition qualify as basic particulars. The fact that identification in general has a temporal as well as a spatial aspect is no objection. For material bodies, or things which have them, exhibit relations between themselves which have a temporal aspect. One thing replaces or begets another. Things pass through places.
It is not, then, only in special circumstances that material bodies, in the broad sense in which I am using the expression, may be identified without reference to particulars of types other than their own. For the fundamental condition of identification without dependence on alien types -- viz. the forming of a comprehensive and sufficiently complex type-homogeneous framework of reference -- is satisfied for the case of material bodies. On the other hand, it is, as we have seen, only in special circumstances that identification of particulars of other types may avoid any dependence on reference to things which are or possess material
bodies. Material bodies, therefore, are basic to particular-identification.
The conclusion may be reinforced by giving the argument a different turn. I have argued that a fundamental condition of identifying reference without dependence on alien types is the possession of a common, comprehensive and sufficiently complex type-homogeneous framework of reference. I have claimed that this condition is satisfied in the case of material bodies, and not generally in other cases. But earlier, in the second part of this chapter, I asserted that a condition, in turn, of the possession of a single, continuously usable framework of. this kind, was the ability to reidentify at least some elements of the framework in spite of discontinuities of observation: that is to say, one must be able to identify some particular things as the same again as those encountered on a previous occasion. Evidently the ability to do this entails the existence of general criteria or methods of reidentification for different kinds of particular. These considerations taken together suggest that, if material bodies are basic from the point of view of referential identification, they must also be basic from the point of view of reidentification. That is to say, the reidentification criteria for material bodies should not be found to turn on the identities of other particulars except such as themselves are or have material bodies, whereas the reidentification criteria for particulars of other categories should be found to turn in part on the identity of material bodies. This expectation is amply fulfilled. If, for example, we take any familiar process-name, such as 'thaw' or 'battle', we shall find it impossible to give a detailed account of means of identifying a particular process of the kind concerned as the same again, which do not involve any reference to some material bodies or other -- either those which make up its setting, its surroundings, or the places through which it passes; or some causally connected with it in some way; or some which the process involves more directly, e.g. the body or bodies undergoing or taking part in it; or some in some other way connected with the identity of the process. If, on the other hand, we consider the identity through time of material bodies themselves, we shall indeed find that a fundamental requirement is that which
we have already noted, viz, continuity of existence in space; and determining whether this requirement is fulfilled may turn on identifying places; but this, in its turn, rests upon the identification of bodies.
Both from the point of view, then, of distinguishing a particular non-demonstratively referred to from others of the same general kind, and from the point of view of identifying a particular encountered on one occasion, or described in respect of one occasion, with a particular encountered on another, or described in respect of another, we find that material bodies play a unique and fundamental role in particular-identification. This conclusion should be in no way surprising or unexpected, if we recall that our general framework of particular-reference is a unified spatiotemporal system of one temporal and three spatial dimensions, and reflect once more that, of the available major categories, that of material bodies is the only one competent to constitute such a framework. For this category alone supplies enduring occupiers of space possessing sufficiently stable relations to meet, and hence to create, the needs with which the use of such a framework confronts us.
Two objections may now be briefly mentioned.
First, it might be objected that the argument rests on a fundamental, but in fact dubious, opposition or contrast between material bodies and processes. After all, it may be said, the erosion of a cliff can last as long as the cliff, and maintain as constant a spatial relation to the erosion of the next cliff as the two cliffs do to each other. The growth and senescence of a man lasts as long as the man, and can also be said to have the same spatial relations at various times to other processes as he is said to have to other things: it goes on just where he is. With what justification is a fundamental distinction of category assumed between things and processes? So some philosophers have reasoned, making their point by saying, for example, that 'Caesar' is the name of a series of events, a biography. In so reasoning, they may be said to draw attention to the possibility of our recognizing a category of objects which we do not in fact recognize: a category of four-dimensional objects, which might be called 'process-things', and of which
each of the temporally successive parts is three-dimensional, is, as it were, the thing taken at successive stages of its history from the beginning to the end. But the way in which I have to describe these objects shows that they are not to be identified either with the processes which things undergo or with the things which undergo them. I remarked earlier that I was concerned to investigate the relations of identifiability-dependence between the available major categories, the categories we actually possess; and the category of process-things is one we neither have nor need. We do in fact distinguish between a thing and its history, or the phases of its history; we cannot appropriately speak of one in the ways appropriate to the other; and we do not speak of either in ways appropriate to the category of process-things. Granted the distinction we do draw, there is, as we have already seen, a general identifiability-dependence of processes which things undergo upon the things which undergo them, and not vice versa. This is partly, though not only, because, granted that distinction, it is the things themselves, and not the processes they undergo, which are the primary occupiers of space, the possessors not only of spatial position, but of spatial dimensions. If one tried to give the spatial dimensions of such a process, say a death or a battle, one could only trace the outline of the dying man or indicate the extent of the ground the battle was fought over.
A more tentative, yet more serious, objection might be advanced. We began by considering a certain type of speech-situaton, that in which identifying references to particulars were made and understood. We were to consider the conditions of successful identification in this kind of situation. Yet it is far from obvious how the very general and theoretical considerations advanced in the course of these arguments bear upon or reflect our actual speech-procedures, and correspondingly far from obvious in what sense, if in any, it has really been established that material bodies and things possessing them enjoy a primacy from the point of view of identification.
This objection must, in a sense, be allowed to stand. It would be a task of enormous complexity to show exactly how these general considerations are related to our actual procedures in
learning and speech. If we attempted it, we should lose the generality in the detail. But a point may be made in mitigation of the refusal to attempt it. Clearly we do not, in ordinary conversation, make explicit the referential frameworks we employ. We do indeed often use demonstratives in reference to things in our immediate surroundings. But when our talk transcends them, we do not elaborately relate the things we speak of to the things we see. The place of the explicit relational framework is taken in part by that linguistic device which has so often and so justly absorbed the attention of logicians -- the proper name. Demonstratives or quasi-demonstratives apart, it is proper names which tend to be the resting-places of reference to particulars, the points on which the descriptive phrases pivot. Now, among particulars, the bearers par excellence of proper names are persons and places. It is a conceptual truth, as we have seen, that places are defined by the relations of material bodies; and it is also a conceptual truth, of which we shall see the significance more fully hereafter, that persons have material bodies.