III. We pass, by imperceptible stages, from recollections strung out along the course of time to the movements which indicate their nascent or pos sible action in space. Lesions of the brain may affect these movements, but not these recollections.
CHAP, n THE TWO FORMS OP MEMORY 89 We have now to see whether experience verifies these three propositions.
I. The two forms of memory. — I study a lesson, and in order to learn it by heart I read it a first time, accentuating every line; I then repeat it a certain number of times. At each repetition there is progress; the words are more and more linked together, and at last make a continuous whole. When that moment comes, it is said that I know my lesson by heart, that it is imprinted on my memory.
I consider now how the lesson has been learnt, and picture to myself the successive phases of the process. Each several reading then recurs to me with its own individuality; I can see it again with the circumstances which attended it then and still form its setting. It is distinguished from those which preceded or followed it by the place which it occupied in time; in short, each reading stands out before my mind as a definite event in my history. Again it will be said that these images are recollections, that they are im printed on my memory. The same words, then, are used in both cases. Do they mean the same thing?
The memory of the lesson, which is remembered in the sense of learnt by heart, has all the marks of a habit. Like a habit, it is acquired by the repetition of the same effort. Like a habit, it demands first a decomposition and then a recom- 90 MATTER AND MEMORY CHAP. 11 position of the whole action. Lastly, like every habitual bodily exercise, it is stored up To learn by.; '. J heart is to in a mechanism which is set in motion cerebral as a whole by an initial impulse, in a a habit of closed system of automatic movements which succeed each other in the same order and, together, take the same length of time. The memory of each several reading, on the contrary, the second or the third for instance, has none of the marks of a habit.
To recall the..
successive Its image was necessarily imprinted stages of. J learning by at once on the memory, since the heart is to..,..
appeal to an other readings form, by their very de- independent...memory. nnition, other recollections. It is like an event in my life; its essence is to bear a date, and consequently to be unable to occur again. All that later readings can add to it will only alter its original nature; and though my effort to recall this image becomes more and more easy as I repeat it, the image, regarded in itself, was necessarily at the outset what it always will be.
It may be urged that these two recollections, that of the reading and that of the lesson, differ only as the less from the more, and that the images successively developed by each repetition overlie each other, so that the lesson once learned is but the composite image in which all readings are blended. And I quite agree that each of the successive readings differs from the preceding mainly in the fact that the lesson is better known.
CHAP, n THE TWO FORMS OF MEMORY QI But it is no less certain that each of them, con sidered as a new reading and not as a lesson better known, is entirely sufficient to itself, subsists ex actly as it occurred, and constitutes with all its concomitant perceptions an original moment of my history. We may even go further and aver that consciousness reveals to us a profound differ ence, a difference in kind, between the two sorts of recollection. The memory of a given reading is a representation, and only a representation; it is embraced in an intuition of the mind which I may lengthen or shorten at will; I assign to it any duration I please; there is nothing to prevent my grasping the whole of it instantaneously, as in one picture. On the contrary, the memory of the lesson I have learnt, even if I repeat this lesson only mentally, requires a definite time, the time necessary to develop one by one, were it only in imagination, all the articulatory movements that are necessary: it is no longer a representation, it is an action. And, in fact, the lesson once learnt bears upon it no mark which betrays its origin and classes it in the past; it is part of my present, exactly like my habit of walking or of writing; it is lived and acted, rather than represented: I might believe it innate, if I did not choose to recall at the same time, as so many representations, the successive readings by means of which I learnt it. Therefore these representations are independent of it, and, just as they preceded the lesson as I now possess and 92 MATTER AND MEMORY CHAP, it know it, so that lesson once learned can do with out them.
Following to the end this fundamental dis tinction, we are confronted by two different memories theoretically independent. The first records, in the form of memory-images, all the events of our daily life as they occur in time; it neglects no detail; it leaves to each fact, to each gesture, its place and date. Regardless of utility or of practical application, it stores up the past by the mere necessity of its own nature. By this memory is made possible the intelligent, or rather intellectual, recognition of a perception already experienced; in it we take refuge every time that, in the search for a particular image, we remount the slope of our past. But everypercep- Habits ti°n is prolonged into a nascent action; E°pStedby and while the images are taking their place an(i order in this memory, the thesS°ddo not movements which continue them modify the organism, and create in the body new dispositions towards action. Thus is gradually formed an experience of an entirely different order, which accumulates within the body, a series of mechanisms wound up and ready, with reactions to external stimuli ever more numerous and more varied, and answers ready prepared to an ever growing number of possible solicitations. We become conscious of these mechanisms as they come into play; and this consciousness of a whole past of efforts stored up in the present is indeed CHAP, n THE TWO FORMS OF MEMORY 93 also a memory, but a memory profoundly differ ent from the first, always bent upon action, seated in the present and looking only to the future. It has retained from the past only the intelli gently coordinated movements which represent the accumulated efforts of the past; and it recovers those past efforts, not in the memory-images which recall them, but in the definite order and systema tic character with which the actual movements take place. In truth, it no longer represents our past to us, it acts it; and if it still deserves the name of memory, it is not because it conserves bygone images, but because it prolongs their use ful effect into the present moment.
Of these two memories, of which the one imagines and the other repeats, the second may such is the suPply the place of the first and even memoiy.ua sometimes be mistaken for it. When a welcomes his master, barking and recognize*, wagging his tail, he certainly recognizes him; but does this recognition imply the evoca tion of a past image and the comparison of that image with the present perception? Does it not rather consist in the animal's consciousness of a certain special attitude adopted by his body, an attitude which has been gradually built up by his familiar relations with his master, and which the mere perception of his master now calls forth in him mechanically? We must not go too far; even in the animal it is possible that vague images of the past overflow into the present perception; 94 MATTER AND MEMORY CHAP, n we can even conceive that its entire past is vir tually indicated in its consciousness; but this past does not interest the animal enough to detach it from the fascinating present, and its recognition must be rather lived than thought. To call up the past in the form of an image, we must be able to withdraw ourselves from the action of the moment, we must have the power to value the useless, we must have the will to dream. Man alone is cap able of such an effort. But even in him the past to which he returns is fugitive, ever on the point of escaping him, as though his backward turning memory were thwarted by the other, more natural, memory, of which the forward movement bears him on to action and to life.
When psychologists talk of recollection as of a fold in a material, as of an impress graven deeper by repetition, they forget that the im- But true > •. r, representative mense majority oi our memories bear memory re-,,.,,.,.£, cords every upon events and details oi our hie of moment 01,.,.,.,,, duration, which the essence is to have a date, each unique,,,, i_i r and not to and consequently to be incapable of be repeated.,.,,,,,.,., being repeated. I he memories which we acquire voluntarily by repetition are rare and exceptional. On the contrary, the record ing, by memory, of facts and images unique in their kind takes place at every moment of duration. But inasmuch as learnt memories are more useful, they are more remarked. And as the acquisition of these memories by a repetition of the same effort resembles the well-known process CHAP, ii THE TWO FORMS OF MEMORY 95 of habit, we prefer to set this kind of memory in the foreground, to erect it into the model memory, and to see in spontaneous recollection only the same phenomenon in a nascent state, the begin ning of a lesson learnt by heart. But how can we overlook the radical difference between that which must be built up by repetition and that which is essentially incapable of being repeated? Spontaneous recollection is perfect from the out set; time can add nothing to its image without disfiguring it; it retains in memory its place and date. On the contrary, a learnt recollection passes out of time in the measure that the lesson is better known; it becomes more and more im personal, more and more foreign to our past life. Repetition, therefore, in no sense effects the con version of the first into the last; its office is merely to utilize more and more the movements by which the first was continued, in order to organize them together and, by setting up a mechanism, to create a bodily habit. Indeed, this habit could not be called a remembrance, were it not that I remember that I have acquired it; and I remem ber its acquisition only because I appeal to that memory which is spontaneous, which dates events and records them but once. Of the two memories, then, which we have just distinguished, the first appears to be memory par excellence. The second, that generally studied by psychologists, is habit interpreted by memory rather than memory itself. It is true that the example of a lesson learnt 96 MATTER AND MEMORY CHAP n by heart is to some extent artificial. Yet our whole life is passed among a limited The normal, / consciousness number of objects, which pass more or calls up only those memory- less often before our eyes: each of images which...,.
can usefully them, as it is perceived, provokes on combine with combine with the present our part movements, at least nascent, whereby we adapt ourselves to it. These movements, as they recur, contrive a mechanism for themselves, grow into a habit, and deter mine in us attitudes which automatically follow our perception of things. This, as we have said, is the main office of our nervous system. The afferent nerves bring to the brain a disturbance, which, after having intelligently chosen its path, transmits itself to motor mechanisms created by re petition. Thus is ensured the appropriate reaction, the correspondence to environment — adaptation, in a word — which is the general aim of life. And a living being which did nothing but live would need no more than this. But, simultaneously with this process of perception and adaptation which ends in the record of the past in the form of motor habits, consciousness, as we have seen, retains the image of the situations through which it has successively travelled, and lays them side by side in the order in which they took place.. Of what use are these memory-images? Preserved in memory, reproduced in consciousness, do they not distort the practical character of life, mingling dream with reality? They would, no doubt, if our actual consciousness, a consciousness which re- CHAP. H THE TWO FORMS OF MEMORY 97 fleets the exact adaptation of our nervous system to the present situation, did not set aside all those among the past images which cannot be co ordinated with the present perception and are unable to form with it a useful combination. At most, certain confused recollections, unrelated to the present circumstances, may overflow the usefully associated images, making around these a less illuminated fringe which fades away into an immense zone of obscurity. But sup pose an accident which upsets the equilibrium maintained by the brain between the external stimulation and the motor reaction, relax for a moment the tension of the threads which go from the periphery to the periphery by way of the centre, and immediately these darkened images come forward into the full light: it is probably the latter condition which is realized in any sleep where in we dream. Of these two memories that we have distinguished, the second, which is active or motor, will, then, constantly inhibit the first, or at least only accept from it that which can throw light upon and complete in a useful way the present situation: thus, as we shall see later, could the laws of the association of ideas be explained. — But, besides the services which they can render by associating with the present perception, the images stored up in the spontaneous memory have yet another use. No doubt they are dream-images; no doubt they usually appear and disappear independently of our will; and 98 MATTER AND MEMORY CHAP. 11 this is why, when we really wish to know a thing, we are obliged to learn it by heart, that is to say, to substitute for the spontaneous image a motor mechanism which can serve in its stead. But there is a certain effort sui generis which permits us to retain the image itself, for a limited time, within the field of our consciousness; and, thanks to this faculty, we have no need to await at the hands of chance the accidental repetition of the same situations, in order to organize into a habit concomitant movements; we make use of the fugitive image to construct a stable mechanism which takes its place. — Either, then, our distinction of the two independent memories is unsound, or, if it corresponds to facts, we shall find an exaltation of spontaneous memory in most cases where the sensori-motor equilibrium of the nervous system is disturbed; an inhibition, on the contrary, in the normal state, of all spontaneous recollections which do not serve to consolidate the present equilibrium; and lastly, in the operation by means of which we acquire the habit-memory, a latent intervention of the image-memory. Let us see whether the facts confirm this hypothesis. For the moment we will insist on neither point; we hope to throw ample light upon both when we study the disturbances of memory and the laws of the association of ideas. We shall be content for the present to show, in regard to things which are learnt, how the two memories run side by side and lend to each other a mutual support. It is CHAP ii. THE TWO FORMS OF MEMORY 99 a matter of every-day experience that lessons committed to the motor memory can be auto matically repeated; but observation of patho logical cases proves that automatism extends Therefore much further in this direction than we think. In cases of dementia, we some- times find that intelligent answers are StenSper- given to a succession of questions which masked'by are not understood: language here works habit memory. after ^ manner of a reflex.1 Aphasics, incapable of uttering a word spontaneously, can recollect without a mistake the words of an air which they sing.1 Or again, they will fluently repeat a prayer, a series of numbers, the days of the week, or the months of the year.8 Thus extremely complex mechanisms, subtle enough to imitate intelligence, can work by themselves when once they have been built up, and in consequence usually obey a mere initial impulse of the will. But what takes place while they are being built up? When we strive to learn a lesson, for in stance, is not the visual or auditory image which we endeavour to reconstitute by movements already in our mind, invisible though present? Even in the very first recitation, we recognize, 1 Robertson, Reflex Speech (Journal of Mental Science, April, 1888). Cf. the article by Ch. Fe're', Le langage reflexe (Revue Philosophique, Jan. 1896).
1 Oppenheim, Ueber das Verhalten der musikalischen Aus- drucksbewegungen bei Aphatischen (Charite Annalen, xiii, 1888, p. 348 et seq.).
8 Ibid., p. 365.
TOO MATTER AND MEMORY CHAP. H by a vague feeling of uneasiness, any error we have made, as though from the obscure depths of consciousness we received a sort of warn ing.1 Concentrate your mind on that sensation, and you will feel that the complete image is there, but evanescent, a phantasm that disappears just at the moment when motor activity tries to fix its outline. During some recent experiments (which, however, were undertaken with quite a different purpose),2 the subjects averred that they felt just such an impression. A series of letters, which they were asked to remember, was held before their eyes for a few seconds. But, to pre vent any accentuating of the letters so perceived by appropriate movements of articulation, they were asked to repeat continuously a given syl lable while their eyes were fixed on the image. From this resulted a special psychical state; the subjects felt themselves to be in complete possession of the visual image, although unable to produce any part of it on demand: to their great surprise the line disappeared. ' According to one observer, the basis was a Gesammtvorstellung, a sort of all-embracing complex idea in which the parts have an indefinitely felt unity.' 3 1 See, on the subject of this sense of error, the article by Miiller and Schumann, Experimentelle Beitrdge zur Untersu- chung des Geddcthtnisses (Zeitschr. /. Psych, u. Phys. der Sinnesorgane (Dec., 1893, p. 305).
2 W. G. Smith, The Relation of A ttentionto Memory. (Mind, Jan. 1895.)
8 Ibid. loc. cit., p. 23.
CHAP, tt THE TWO FORMS OF MEMORY 101 This spontaneous recollection, which is masked by the acquired recollection, may flash out at intervals; but it disappears at the least move ment of the voluntary memory. If the subject sees the series of letters, of which he thought he retained the image, vanish from before his eyes, this happens mainly when he begins to repeat it: the effort seems to drive the rest of the image out of his consciousness.1 Now, analyse many of the imaginative methods of mnenomics and you will find that the object of this science is to bring into the foreground the spontaneous memory which was hidden, and to place it, as an active memory, at our service; to this end every attempt at motor memory is, to begin with, suppressed. The faculty of mental photography, says one author,2 belongs rather to subconsciousness than 1 Something of this nature appears to take place in that affection which German authors call Dyslexic. The patient reads the first words of a sentence aright, and then stops abruptly, unable to go on, as though the movements of articulation had inhibited memory. See, on the subject of dyslexic: Berlin, Eine besondere Art der Wortblindheit (Dyslexie), Wiesbaden, 1887, and Sommer, Die Dyslexic als functionelle Storung (Arch. f. Psychiatrie, 1893). We may also compare with these phenomena the remarkable cases of word deafness in which the patient understands the speech of others, but no longer understands his own. (See examples cited by Bateman, On Aphasia, p. 200; by Bernard, De I'aphasie, Paris 1889, pp. 143 and 144; and by Broadbent, Case of Peculiar Affection of Speech, Brain, 1878-9, p. 484 et seq.).
2 Mortimer Granville, Ways of remembering. (Lancet, Sept. 27. 1899, p. 458.; 102 MATTER AND MEMORY CHAP, n to consciousness; it answers with difficulty to the summons of the will. In order to exercise it, we should accustom ourselves to retaining, for instance, several arrangements of points at once, without even thinking of counting them x: we must imitate in some sort the instantaneity of this memory in order to attain to its mastery. Even so it remains capricious in its manifesta tions; and as the recollections which it brings us are akin to dreams, its more regular intrusion into the life of the mind may seriously disturb intellectual equilibrium.
What this memory is, whence it is derived and how it works, will be shown in the next chapter. For the moment, the schematic conception will be enough. So we shall merely sum up the pre ceding paragraphs and say that the past appears indeed to be stored up, as we had surmised, under two extreme forms: on the one hand, motor mechanisms which make use of it; on the other, personal memory-images which picture all past events with their outline, their colour and their place in time. Of these two memories the first follows the direction of nature; the second, left to itself, would rather go the contrary way. The first, conquered by effort, remains depen- | dent upon our will; the second, entirely spon taneous, is as capricious in reproducing as it is faithful in preserving. The only regular and 1 Kay, Memory and how to improve it. New York, 1888.
CHAP, n THE TWO FORMS OF MEMORY 103 certain service which the second memory can render to the first is to bring before it images of what preceded or followed situations similar to the present situation, so as to guide its choice: in this consists the association of ideas. There is no other case in which the memory which recalls is sure to obey the memory which repeats. Every where else, we prefer to construct a mechanism which allows us to sketch the image again, at need, because we are well aware that we cannot count upon its reappearance. These are the two extreme forms of memory in their pure state.