Local signs. tion, but it will be convenient to include it when speaking impatience, that this amounts to the monstrous absurdity | hardly perhaps implied in the mere massiveness of a sensa- 1 To illustrate what is meant by different complexes it will be enough to refer to the psychological implications of the fact that scarcely two portions of the sensitive surface of the human body are anatomically alike. Not only in the distribution and character of the nerve-endings but in the variety of the underlying parts-in one place bone, in another fatty tissue, in others tendons or muscles variously arranged-we find ample ground for diversity in "the local colouring of sensations. And comparative zoology helps us to see how such diversity has been developed as external impressions and the answering movements have gradually differentiated an organism originally almost homogeneous and symmetrical. Between one point and another on the surface of a sphere there is no ground of difference; but 2 The improvements in the sensibility of our spatial sense consequent on its variations under practice, the action of drugs, &c., are It must seem strange, if this conception of extensity is essential to a psychological theory of space, that it has escaped notice so long. The reason may be that in investigations into the origin of our knowledge of space it was always the conception of space and not our concrete space perceptions that came up for examination. Now in space as we conceive it one position is distinguishable from another solely by its co-ordinates, i.e., by the magnitude and signs of certain lines and angles, as referred to a certain datum position, or origin; and these elements our motor experiences seem fully to explain. But on reflexion we ought, surely, to be puzzled by the question, how these coexistent positions could be known before those movements were made which constitute them different positions. The link we thus suspect to be missing is supplied by the more concrete experiences we obtain from our own body, in which two positions have a qualitative difference or "local colour" independently of movement. True, such positions would not be known as spatial without movement; but neither would the movement be known as spatial had those positions no other difference than such as arises from movement. We may now consider the part which movement plays Movein elaborating the presentations of this dimensionless ment. continuum into perceptions of space. In so doing we must bear in mind that this continuum implies the incopresentability of two impressions having the same local sign, but allows not only of the presentation of impressions of varying massiveness but of several distinct impressions at the same time. As regards the motor element itself, the first point of importance is the incopresentability and invariability of a series of auxilio-motor presentations, PPPP4 P1 cannot be presented along with P2, and from P it is impossible to reach P1 again save through P3 and P. Such a series, taken alone, could afford us, it is evident, nothing but the knowledge of an invariable sequence of impressions which it was in our own power to produce. Its psychological interest would lie solely in the fact that, whereas other impressions depend on an objective initiative, these depend on a subjective. But in the course of the movements necessary to the exploration of obviously no real contradiction to this; on the contrary, such facts are all in favour of making extensity a distinct factor in our space experience and one more fundamental than that of movement. the body-probably our earliest lesson in spatial perception | But in the evolution of our spatial experience impressions and -these auxilio-motor presentations receive a new significance from the active and passive touches that accompany them, just as they impart to these last a significance they could never have alone. It is only in the resulting complex that we have the presentations of position and of spatial magnitude. For space, though conceived as a coexistent continuum, excludes the notion of omnipresence or ubiquity; two positions la and 1, must coexist, but they are not strictly distinct positions so long as we conceive ourselves present in the same sense in both. But, if F and F, are, e.g., two impressions produced by compass-points touching two different spots as 7 and 1, on the hand or arm, and we place a finger upon and move it to l,, experiencing thereby the series P1, P2P3,P4, this series constitutes la and l, into positions and also invests F and F, with a relation not of mere distinctness but of definite distance. The resulting complex perhaps admits of symbolization as follows:Fa Fb Fc Fd F. F, F, Fr Fr Tttt P1PaPa Ps 1 Here the first line represents a portion of the tactual continuum, F and F, being distinct "feels," if we may so say, or passive touches presented along with the fainter sensations of the continuum as a whole; T stands for the active touch of the exploring finger and P1 for the corresponding auxilio-motor object; the rest of the succession, as not actually present at this stage but capable of revival from past explorations, is symbolized by the ttt and P2P3P4 When the series of movements is accompanied by active touches without passive there arises the distinction between one's own body and foreign bodies; when the initial movement of a series is accompanied by both active and passive touches, the final movement by active touches only, and the intermediate movements are unaccompanied by either, we get the further presentation of empty space lying between us and them, but only when by frequent experience of contacts along with those intermediate movements we have come to know all movement as not only succession but change of position. Thus active touches come at length to be projected, passive touches alone being localized in the stricter sense. But in actual fact, of course, the localization of one impression is not perfected before that of another is begun, and we must take care lest our necessarily meagre exposition give rise to the mistaken notion that localizing an impression consists wholly and solely in performing or imaging the particular movements necessary to add active touches to a group of passive impressions. That this cannot suffice is evident merely from the consideration that a single position out of relation to all other positions is a contradiction. Localization, though it depends on many special experiences of the kind described, is not like an artificial product which is completed a part at a time, but is essentially a growth, its several constituent localizations advancing together in definiteness and interconnexion. So far has this development advanced that we do not even imagine the special movements which the localization of an impression implies, that is to say, they are no longer distinctly represented as they would be if we definitely intended to make them: the past experiences are "retained," but too much blended in the mere perception to be appropriately spoken of as remembered or imaged. Apropos of this almost instinctive character of even our earliest spatial perceptions it will be appropriate to animadvert on a misleading implication in the current use of such terms as "localization," projection," "bodily reference," "spatial reference," and the like. The implication is that external space, or the body as extended, is in some sort presented or supposed apart from the localization, projection, or reference of impressions to such space. That it may be possible to put a book in its place on a shelf there must be (1) the book, and (2), distinct and apart from it, the place on the shelf. positions are not thus presented apart. We can have, or at least localized; but if it is localized this means that a more complex we can suppose, an impression which is recognized without being presentation is formed by the addition of new elements, not that a second distinct object is presented and some indescribable connexion established between the impression and it, still less that the impression is referred to something not strictly presented at all. The truth is that the body as extended is from the psychological point of view not perceived at all apart from localized impressions. In like manner impressions projected (or the absence of impressions projected) constitute all that is perceived as the occupied (or unoccupied) space beyond. It is not till a much later stage, after many varying experiences of different impressions similarly localized or projected, that even the mere materials are present for the formation of such an abstract conception of space as "spatial reference" implies. Psychologists, being themselves at this later stage, are apt to commit the oversight of introducing it into the earlier stage which they have to expound. In a complex presentation, such as that of an orange or Intuition a piece of wax, may be distinguished the following points of things. concerning which psychology may be expected to give an account:-(a) its reality, (b) its solidity or occupation of space, (c) its permanence, or rather its continuity in time, (d) its unity and complexity, and (e) its substantiality and the connexion of its attributes and powers. Though, in fact, these items are most intimately blended, our exposition will be clearer if we consider each for a moment apart. 1 (a) The terms actuality and reality have each more Actualthan one meaning. Thus what is real, in the sense of ity or reality. material, is opposed to what is mental; as the existent or actual it is opposed to the non-existent; and again, what is actual is distinguished from what is possible or necessary. But here both terms, with a certain shade of difference, in so far as actual is more appropriate to movements and events, are used, in antithesis to whatever is ideal or represented, for what is sense-given or presented. This seems at least their primary psychological meaning; and it is the one most in vogue in English philosophy at any rate, over-tinged as that is with psychology. Any examination of this characteristic will be best deferred till we come to deal with ideation generally (see p. 58 below). Meanwhile it may suffice to remark that reality or actuality is not a single distinct element added to the others which enter into the complex presentation we call a thing, as colour or solidity may be. Neither is it a special relation among these elements, like that of substance and attribute, for example. In these respects the real and the ideal, the actual and the possible, are alike; all the elements or qualities within the complex, and all the relations of those elements to each other, are the same in the rose repreThe difference turns not sented as in the presented rose. upon what these elements are, regarded as qualities or relations presented or represented, but upon whatever it is that distinguishes the presentation from the representation of any given qualities or relations. Now this, as we shall see, turns partly upon the relation of such complex presentation to other presentations in consciousness with it, partly upon its relation as a presentation to the subject whose presentation it is. In this respect we find a difference, not only between the simple qualities, such as cold, hard, red, and sweet in strawberry ice, e.g., as presented and as represented, but also, though less conspicuously, in the spatial, and even the temporal, relations which enter into our intuition as distinct from our imagination of it. Where no such difference exists we have passed beyond 1 Thus Locke says, "Our simple ideas [i.e., presentations or impressions, as we should now say] are all real and not fictions at pleasure; for the mind can make to itself no simple idea more than what it has received" (Essay, ii. 30, 2). And Berkeley says, "The ideas imprinted on the senses by the Author of Nature are called real things; and those excited in the imagination, being less regular, vivid, and constant, are more properly termed ideas or images of things, which they copy or represent" (Prin. of Hum, Know., part i. § 33). the distinction of percept and image to the higher level of Impene- (6) Here our properly motor presentations or "feelings Unity ness. The first step in this process has been the simultane- tinuity. (d) Amidst all the change above described there is one Tempothing comparatively fixed: our own body is both constant ral conas a group and a constant item in every field of groups; and not only so, but it is beyond all other things an object of constant and peculiar interest, inasmuch as our earliest pleasures and pains depend solely upon it and what affects it. The body becomes, in fact, the earliest form of self, the first datum for our later conceptions of permanence and individuality. A continuity like that of self is then transferred to other bodies which resemble our own, so far as our direct experience goes, in passing continuously from place to place and undergoing only partial and gradual changes of form and quality. As we have existed-or, more exactly, as the body has been continuously presented during the interval between two encounters with some other recognized body, so this is regarded as having continuously existed during its absence from us. However permanent we suppose the conscious subject to be, it is hard to see how, without the continuous presentation to it of such a group as the bodily self, we should ever be prompted to resolve the discontinuous presentations of external things into a continuity of existence. It might be said: "Since the second presentation of a particular group would, by the mere workings of psychical laws, coalesce or become identical with the image of the first, this coalescence suffices to 'generate' the conception of continued existence." But such assimilation is only the ground of an intellectual identification and furnishes no motive, one way or the other, for resolving two like things into the same thing: between a second presentation of A and the presentation at different times of two A's there is so far no difference. Real identity no more involves But for its familiarity we should marvel at the fact that exact similarity than exact similarity involves sameness of out of the variety of impressions simultaneously presented things; on the contrary, we are wont to find the same thing we do not instantly group together all the sounds and all alter with time, so that exact similarity after an interval, so the colours, all the touches and all the smells, but, divid- far from suggesting one thing, is often the surest proof that ing what is given together, single out a certain sound or there are two concerned. Of such real identity, then, it smell as belonging with a certain colour and feel, similarly would seem we must have direct experience; and we have singled out from the rest, to what we call one thing. We it in the continuous presentation of the bodily self; apart might wonder, too-those at least who have made so much from this it could not be " generated" by association of association by similarity ought to wonder-that, say, the among changing presentations. Other bodies being in white of snow calls up directly, not other shades of white or the first instance personified, that then is regarded as one other colours, but the expectation of cold or of powdery soft-thing-from whatever point of view we look at it, whether (c) The remaining important factors in the psychologiand com- cal constitution of things might be described in general plexity. terms as the time-relations of their components. Such relations are themselves in no way psychologically determined; impressions recur with a certain order or want of order quite independently of the subject's interest or of any psychological principles of synthesis or association whatever. It is essential that impressions should recur, and recur as they have previously occurred, if knowledge is ever to begin; out of a continual chaos of sensation, all matter and no form, such as some philosophers describe, nothing but chaos could result. But a flux of impressions having this real or sense-given order will not suffice; there must be also attention to and retention of the order, and these indispensable processes at least are psychological. Still they need not be further emphasized here, nor would it have been necessary at this point to call them to mind at all had not British empirical philosophers brought psychology into disrepute by overlooking them altogether. as part of a larger thing or as itself compounded of such parts-which has had one beginning in time. But what is it that has thus a beginning and continues indefinitely? This leads to our last point. Substan. (e) So far we have been concerned only with the comtiality. bination of sensory and motor presentations into groups and with the differentiation of group from group; the relations to each other of the constituents of each group still for the most part remain. To these relations in the main must be referred the correlative conceptions of substance and attribute, the distinction in substances of qualities and powers, of primary qualities and secondary, and the like.1 Impres sions and ideas, Of all the constituents of things only one is universally present, that above described as physical solidity, which presents itself according to circumstances as impenetrability, resistance, or weight. Things differing in temperature, colour, taste, and smell agree in resisting compression, in filling space. Because of this quality we regard the wind as a thing, though it has neither shape nor colour, while a shadow, though it has both but not resistance, is the very type of nothingness. This constituent is invariable, while other qualities are either absent or change,-form altering, colour disappearing with light, sound and smells intermitting. Many of the other qualities-colour, temperature, sound, smell-increase in intensity until we reach and touch a body occupying space; with the same movement too its visual magnitude varies. At the moment of contact an unvarying tactual magnitude is ascertained, while the other qualities and the visual magnitude reach. a fixed maximum; then first it becomes possible by effort to change or attempt to change the position and form of what we apprehend. This tangible plenum we thenceforth regard as the seat and source of all the qualities we project into it. In other words, that which occupies space is psychologically the substantial; the other real constituents are but its properties or attributes, the marks or manifestations which lead us to expect its presence. Imagination or Ideation. pressions. "That idea of red," says Hume, "which we | form in the dark and that impression which strikes our eyes in the sunshine differ only in degree, not in nature."3 But what he seems to overlook is that, whereas there can be a mere sensation red-and such a presentation may for present purposes be regarded as simple we can only have an image or representation of a red thing or a red form, i.e., of red in some way ideally projected or intuited. In other words, there are no ideas answering to simple or isolated impressions: what are revived in memory and imagination are percepts, not unlocalized sensations and movements. It is not only that we cannot now directly observe such representations,—because, for that matter, we can no longer directly observe even the original presentations as merely elementary impressions; the point rather is that ideas as such are from the first complex, and do not begin to appear in consciousness apart from the impressions which they are said to reproduce till after these impressions have been frequently attended to together, and have been more or less firmly synthesized into percepts or intuitions. The effects of even the earliest of these syntheses or "associations' of impressions must of course in some way persist, or progress in perception would be impossible. On this account it has been usual to say that "perception" implies both "memory" and "imagination"; but such a statement can be allowed only so long as these terms are vaguely used. The dog's mouth waters only at the sight of food, but the gourmand's mouth will also water at the thought of it. We recognize the smell of violets as certainly as we recognize the colour when the spring brings them round again; but few persons, if any, can recall the scent when the flower has gone, so as to say with Shelley "Odours, when sweet violets sicken, though most can recall the colour with tolerable clearness. In like manner everybody can perform innumerable complex voluntary movements which only a few can mentally rehearse or describe without the prompting of actual execution. And not only does such reproduction as suffices for perception fall short of that involved in reminiscence or memory in the narrower sense, but the manner in which the constituent elements in a perception are combined differs materially from what is strictly to be called the association of ideas. To realize this difference we need only to observe first how the sight of a suit of polished armour, for example, Before the intuition of things has reached a stage so instantly reinstates and steadily maintains all that we retain of complete and definite as that just described, imagination former sensations of its hardness and smoothness and coldness, or ideation as distinct from perception has well begun. and then to observe how this same sight gradually calls up ideas In passing to the consideration of this higher form of now of tournaments, now of crusades, and so through all the changing imagery of romance. Though the percept is complex, mental life we have to note the distinction between im- it is but a single whole, and the act of perception is single too; pressions and images or ideas, to which Hume first gave but, where, as is the case in memory and imagination, attention general currency. Hume did not think it "necessary to passes, whether voluntarily or non-voluntarily, from one representation to another, it is obvious that these several objects of employ many words in explaining this distinction. Every attention are still distinct and that it is directed in turn to each. one of himself will readily perceive the difference ..; The term "association seems only appropriate to the latter: To though it is not impossible but in particular instances the connexion of the partial presentations in a complex, whether they may very nearly approach to each other. Thus in perception or idea, it would be better to apply the term "complication," which was used in this sense by Herbart, and has been so sleep, in a fever, in madness, or in any very violent emotions used by many psychologists since. When we perceive an orange of soul, our ideas may approach to our impressions; as, by sight we may say that its taste or feel is represented, when we on the other hand, it sometimes happens our impressions perceive it by touch we may in like manner say that its colour is are so faint and low that we cannot distinguish them from represented, symbolizing the whole complex in the first case our ideas." In most cases, no doubt, the obvious differ- sufficiently for our present purpose as Ctf, in the second as Fct. We might also symbolize the idea of an orange as seen by c' tf and ence in intensity, or, as Hume puts it, "in the force or the idea of an orange as felt by f'ct, using the accented letter to liveliness with which they strike upon the mind," is a signify that different constituents are dominant in the two cases. sufficient characteristic, but we must examine a good deal What we have, then, to observe is briefly (1) that the processes further and pay more attention to his uncertain cases if by which the whole complex c'tf or fet is brought into consciousness differ importantly from the process by which C or Freinthis important distinction is ever to be in any sense states and maintains tf or c t, and (2) that e, f, and never have psychologically "explained." that distinct existence as representations which they had as presentations or impressions. To begin with, it is very questionable whether Hume was right in applying Locke's distinction of simple and complex to ideas in the narrower sense as well as to im The distinction between the thing and its properties, like all the foregoing distinctions, is one that might be more fully treated under the head of "Thought and Conception." Still, inasmuch as the material warrant for these concepts is contained more or less implicitly in our percepts, some consideration of it is in place here. Treatise of Human Nature, book i. part i. § 1. The mental synthesis which has taken place in the evolu tion of the percept can only partially fail in the idea, and never so far as to leave us with a chaotic "manifold" of mere sensational remnants. On the contrary, we find that in "constructive imagination" a new kind of effort is often requisite in order to dissociate these representational com Charac plexes as a preliminary to new combinations. But it is | psychological continuity. The impressions entering con- The most obvious, if not the most invariable, difference The superior steadiness just mentioned is perhaps a more constant and not less striking characteristic of percepts. Ideas are not only in a continual flux, but even when we attempt forcibly to detain one it varies continually in clearness and completeness, reminding one of nothing so much as of the illuminated devices made of gas jets, common at fêtes, when the wind sweeps across them, momentarily obliterating one part and at the same time intensifying another. There is not this perpetual flow and flicker in what we perceive; for this, unlike the train of ideas, has at the outset neither a logical nor a sciousness at any one moment are psychologically inde- This contrariety between impression and image suggests, Impressions, then, have no associates to whose presence 1 Moreover, as we shall see, the distinction between present and past or future psychologically presupposes the contrast of impression and image. |