Chapter X: Illusions of Memory (2)

It is evident that this class of mnemonic illusions approximates in character to illusions of perception. When the imagination supplies the interpretation at the very time, and the mind reads this into the perceived object, the error is one of perception. When the addition is made afterwards, on reflecting upon the perception, the error is one of memory. The "fallacies of testimony" which depend on an adulteration of pure observation with inference and conjecture, as, for example, the inaccurate and wild statements of people respecting their experiences at spiritualist _séances_, while they illustrate the curious blending of both kinds of error, are probably much oftener illusions of memory than of perception.[125]

Although in many cases we can account to ourselves for this confusion of fact and imagination, in other cases it is difficult to see any close relation between the fact remembered and the foreign element imported into it. An idea of memory seems sometimes to lose its proper moorings, so to speak; to drift about helplessly among other ideas, and finally, by some chance, to hook itself on to one of these, as though it naturally belonged to it. Anybody who has had an opportunity of carefully testing the truthfulness of his recollection of some remote event in early life will have found how oddly extraneous elements become incorporated into the memorial picture. Incidents get put into wrong places, the wrong persons are introduced into a scene, and so on. Here again we may illustrate the mnemonic illusion by a visual one. When a tree standing before or behind a house and projecting above or to the side of it is not sharply distinguished from the latter, it may serve to give it a very odd appearance.

These confusions of the mental image may arise even when only a short interval has elapsed. In the case of many of the fleeting impressions that are only half recollected, this kind of error is very easy. Thus, for example, I may have lent a book to a friend last week. I really remember the act of lending it, but have forgotten the person. But I am not aware of this. The picture of memory has unknowingly to myself been filled up by this unconscious process of shifting and rearrangement, and the idea of another person has by some odd accident got substituted for that of the real borrower. If we could go deeply enough into the matter, we should, of course, be able to explain why this particular confusion arose. We might find, for example, that the two persons were associated in my mind by a link of resemblance, or that I had dealings with the other person about the same time. Similarly, when we manage to join an event to a wrong place, we may find that it is because we heard of the occurrence when staying at the particular locality, or in some other way had the image of the place closely associated in our minds with the event. But often we are wholly unable to explain the displacement.

So far I have been speaking of the passive processes by which the past comes to wear a new face to our imaginations. In these our present habits of feeling and thinking take no part; all is the work of the past, of the decay of memory, and the gradual confusion of images. This process of disorganization may be likened to the action of damp on some old manuscript, obliterating some parts, altering the appearance of others, and even dislocating certain portions. Besides this passive process of transformation, there is a more active one in which our present minds co-operate. In memory, as in perception and introspection, there is a process of preparation or preadjustment of mind, and here will be found room for what I had called active error. This may be illustrated by the operation of "interpreting" an old manuscript which has got partially obliterated, or of "restoring" a faded picture; in each of which operations error will be pretty sure to creep in through an importation of the restorer's own ideas into the relic of the past.

Just as when distant objects are seen mistily our imaginations come into play, leading us to fancy that we see something completely and distinctly, so when the images of memory become dim, our present imagination helps to restore them, putting a new patch into the old garment. If only there is some relic of the past event preserved, a bare suggestion of the way in which it may have happened will often suffice to produce the conviction that it actually did happen in this way. The suggestions that naturally arise in our minds at such times will bear the stamp of our present modes of experience and habits of thought. Hence, in trying to reconstruct the remote past, we are constantly in danger of importing our present selves into our past selves.

The kind of illusion of memory which thus depends on the spontaneous or independent activity of present imagination is strikingly illustrated in the curious cases of mistaken identity with which the proceedings of our law courts supply us from time to time. When a witness in good faith, but erroneously, affirms that a man is the same as an old acquaintance of his, we may feel sure that there is some striking point or points of similarity between the two persons. But this of itself would only partly account for the illusion, since we often see new faces that, by a number of curious points of affinity, call up in a tantalizing way old and familiar ones. What helps in this case to produce the illusion is the preconception that the present man is the witness's old friend. That is to say, his recollection is partly true, though largely false. He does really recall the similar feature, movement, or tone of voice; he only seems to himself to recall the rest of his friend's appearance; for, to speak correctly, he projects the present impression into the past, and constructs his friend's face out of elements supplied by the new one. Owing to this cause, an illusion of memory is apt to multiply itself, one man's assertion of what happened producing by contagion a counterfeit of memory's record in other minds.

I said just now that we tend to project our present modes of experience into the past. We paint our past in the hues of the present. Thus we imagine that things which impressed us in some remote period of life must answer to what is impressive in our present stage of mental development. For example, a person recalls a hill near the home of his childhood, and has the conviction that it was of great height. On revisiting the place he finds that the eminence is quite insignificant. How can we account for this? For one thing, it is to be observed that to his undeveloped childish muscles the climbing to the top meant a considerable expenditure of energy, to be followed by a sense of fatigue. The man remembers these feelings, and "unconsciously reasoning" by present experience, that is to say, by the amount of walking which would now produce this sense of fatigue, imagines that the height was vastly greater than it really was. Another reason is, of course, that a wider knowledge of mountains has resulted in a great alteration of the man's standard of height.

From this cause arises a tendency generally to exaggerate the impressions of early life. Youth is the period of novel effects, when all the world is fresh, and new and striking impressions crowd in thickly on the mind. Consequently, it takes much less to produce a given amount of mental excitation in childhood than in after-life. In looking back on this part of our history, we recall for the most part just those events and scenes which deeply stirred our minds by their strangeness, novelty, etc., and so impressed themselves on the tablet of our memory; and it is this sense of something out of the ordinary beat that gives the characteristic colour to our recollection. In other words, we remember something as wonderful, admirable, exceptionally delightful, and so on, rather than as a definitely imagined event. This being so, we unconsciously transform the past occurrence by reasoning from our present standard of what is impressive. Who has not felt an unpleasant disenchantment on revisiting some church, house, or park that seemed a wondrous paradise to his young eyes? All our feelings are capable of leading us into this kind of illusion. What seemed beautiful or awful to us as children, is now pictured in imagination as corresponding to what moves our mature minds to delight or awe. One cannot help wondering what we should think of our early heroes or heroines if we could see them again with our adult eyes exactly as they were.

While the past may thus take on an illusory hue through the very progress of our experience and our emotional life, it may become further transformed by a more conscious process, namely, the idealizing touch of a present feeling. The way in which the emotions of love, reverence, and so on, thus transform their lost objects is too well known to need illustration. Speaking generally, we may say that in healthy minds the play of these impulses of feeling results in a softening of the harsher features of the past, and in an idealization of its happier and brighter aspects. As Wordsworth says, we may assign to Memory a pencil--

"That, softening objects, sometimes even
Outstrips the heart's demand;

"That smoothes foregone distress, the lines
Of lingering care subdues,
Long-vanished happiness refines,
And clothes in brighter hues."[126]

Enough has now been said, perhaps, to show in how many ways our retrospective imagination transforms the actual events of our past life. So thoroughly, indeed, do the relics of this past get shaken together in new kaleidoscopic combinations, so much of the result of later experiences gets imported into our early years, that it may well be asked whether, if the record of our actual life were ever read out to us, we should be able to recognize it. It looks as though we could be sure of recalling only recent events with any degree of accuracy and completeness. As soon as they recede at any considerable distance from us, they are subject to a sort of atmospheric effect. Much grows indistinct and drops altogether out of sight, and what is still seen often takes a new and grotesquely unlike shape. More than this, the play of fancy, like the action of some refracting medium, bends and distorts the outlines of memory's objects, making them wholly unlike the originals.

_Hallucinations of Memory._

We will now go on to the third class of mnemonic error, which I have called the spectra of memory, where there is not simply a transformation of the past event, but a complete imaginative creation of it. This class of error corresponds, as I have observed, to an hallucination in the region of sense-perception. And just as we distinguished between those hallucinations of sense which arise first of all through some peripherally caused subjective sensation, and those which want even this element of reality and depend altogether on the activity of imagination, so we may mark off two classes of mnemonic hallucination. The false recollection may correspond to something past--and to this extent be a recollection--though not to any objective fact, but only to a subjective representation of such a fact, as, for example, a dream. In this case the imitation of the mnemonic process may be very definite and complete. Or the false recollection may be wholly a retrojection of a present mental image, and so by no stretch of language be deserving of the name recollection.

It is doubtful whether by any effort of will a person could bring himself to regard a figment of his present imagination as representative of a past reality. Definite and complete hallucinations of this sort do not in normal circumstances arise. It seems necessary for a complete illusion of memory that there should be something past and recovered at the moment, though this may not be a real personal experience.[127] On the other hand, it is possible, as we shall presently see, under certain circumstances, to create out of present materials, and in a vague and indefinite shape, pure phantoms of past experience, that is to say, quasi-mnemonic images to which there correspond no past occurrences whatever.

All recollection, as we have seen, takes place by means of a present mental image which returns with a certain degree of vividness, and is instantaneously identified with some past event. In many cases this instinctive process of identification proves to be legitimate, for, as a matter of fact, real impressions are the first and the commonest source of such lively mnemonic images. But it is not always so. There are other sources of our mental imagery which compete, so to speak, with the region of real personal experience. And sometimes these leave behind them a vivid image having all the appearance of a genuine mnemonic image. When this is so, it is impossible by a mere introspective glance to detect the falsity of the message from the past. We are in the same position as the purchaser in a jet market, where a spurious commodity has got inextricably mixed up with the genuine, and there is no ready criterion by which he can distinguish the true from the false. Such a person, if he purchases freely, is pretty sure to make a number of mistakes. Similarly, all of us are liable to take counterfeit mnemonic images for genuine ones; that is to say, to fall into an illusion of "recollecting" what never really took place.

But what, it may be asked, are these false and illegitimate sources of mnemonic images, these unauthorized mints which issue a spurious mental coinage, and so confuse the genuine currency? They consist of two regions of our internal mental life, which most closely resemble the actual perception of real things in vividness and force, namely, dream-consciousness and waking imagination. Each of these may introduce into the mind vivid images which afterwards tend, under certain circumstances, to assume the guise of recollections of actual events.

That our dream-experience may now and again lead us into illusory recollection has already been hinted. And it is easy to understand why this is so. When dreaming we have, as we have seen, a mental experience which closely approximates in intensity and reality to that of waking perception. Consequently, dreams may leave behind them, for a time, vivid images which simulate the appearance of real images of memory. Most of us, perhaps, have felt this after-effect of dreaming on our waking thoughts. It is sometimes very hard to shake off the impression left by a vivid dream, as, for example, that a dead friend has returned to life. During the day that follows the dream, we have at intermittent moments something like an assurance that we have seen our lost friend; and though we immediately correct the impression by reflecting that we are recalling but a dream, it tends to revive within us with a strange pertinacity.

In addition to this proximate effect of a dream in disturbing the normal process of recollection, there is reason to suppose that dreams may exert a more remote effect on our memories. So widely different in its form is our dreaming from our waking experience, that our dreams are rarely recalled as wholes with perfect distinctness. They revive in us only as disjointed fragments, and only for brief moments when some accidental resemblance in the present happens to stir the latent trace they have left on our minds. We get sudden flashes out of our dream-world, and the process is too rapid, too incomplete for us to identify the region whence the flashes come.

It is highly probable that our dreams are, to a large extent, answerable for the sense of familiarity that we sometimes experience in visiting a new locality or in seeing a new face. If, as we have found some of the best authorities saying, we are, when asleep, always dreaming more or less distinctly, and if, as we know, dreaming is a continual process of transformation of our waking impressions in new combinations, it is not surprising that our dreams should sometimes take the form of forecasts of our waking life, and that consequently objects and scenes of this life never before seen should now and again wear a familiar look.

That some instances of this puzzling sense of familiarity can be explained in this way is proved. Thus, Paul Radestock, in the work _Schlaf und Traum_, already quoted, tells us: "When I have been taking a walk, with my thoughts quite unfettered, the idea has often occurred to me that I had seen, heard, or thought of this or that thing once before, without being able to recall when, where, and in what circumstances. This happened at the time when, with a view to the publication of the present work, I was in the habit of keeping an exact record of my dreams. Consequently, I was able to turn to this after these impressions, and on doing so I generally found the conjecture confirmed that I had previously dreamt something like it." Scientific inquiry is often said to destroy all beautiful thoughts about nature and life; but while it destroys it creates. Is it not almost a romantic idea that just as our waking life images itself in our dreams, so our dream-life may send back some of its shadowy phantoms into our prosaic every-day world, touching this with something of its own weird beauty?

Not only may dreams beget these momentary illusions of memory, they may give rise to something like permanent illusions. If a dream serves to connect a certain idea with a place or person, and subsequent experience does not tend to correct this, we may keep the belief that we have actually witnessed the event. And we may naturally expect that this result will occur most frequently in the case of those who habitually dream vividly, as young children.

It seems to me that many of the quaint fancies which children get into their heads about things they hear of arise in this way. I know a person who, when a child, got the notion that when his baby-brother was weaned, he was taken up on a grassy hill and tossed about. He had a vivid idea of having seen this curious ceremony. He has in vain tried to get an explanation of this picturesque rendering of an incident of babyhood from his friends, and has come to the conclusion that it was the result of a dream. If, as seems probable, children's dreams thus give rise to subsequent illusions of memory, the fact would throw a curious light on some of the startling quasi-records of childish experience to be met with in autobiographical literature.

Odd though it may at first appear, old age is said to resemble youth in this confusion of dream-recollection with the memory of waking experience. Dr. Carpenter[128] tells us of "a lady of advanced age who ... continually dreams about passing events, and seems entirely unable to distinguish between her dreaming and her waking experiences, narrating the former with implicit belief in them, and giving directions based on them." This confusion in the case of the old may possibly arise not from an increase in the intensity of the dreams, but from a decrease in the intensity of the waking impressions. As Sir Henry Holland remarks,[129] in old age life approaches to the state of a dream.

The other source of what may, by analogy with the hallucinations of sense, be called the peripherally originating spectra of memory is waking imagination. In certain morbid conditions of mind, and in the case of the few healthy minds endowed with special imaginative force, the products of this mental activity, may, as we saw when dealing with illusions of perception, closely resemble dreams in their vividness and apparent actuality. When this is the case, illusions of memory may arise at once just as in the case of dreams. This will happen more easily when the imagination has for some time been occupied with the same group of ideal scenes, persons, or events. To Dickens, as is well known, his fictitious characters were for the time realities, and after he had finished his story their forms and their doings lingered with him, assuming the aspect of personal recollections. So, too, the energetic activity of imagination which accompanies a deep and absorbing sympathy with another's painful experiences, may easily result in so vivid a realization of all their details as to leave an after-sense of _personal_ suffering. All highly sympathetic persons who have closely accompanied beloved friends through a great sorrow have known something of this subsequent feeling.

The close connection and continuity between normal and abnormal states of mind is illustrated in the fact that in insanity the illusion of taking past imaginations for past realities becomes far more powerful and persistent. Abercrombie (_Intellectual Powers_, Part III. sec. iv. § 2, "Insanity") speaks of "visions of the imagination which have formerly been indulged in of that kind which we call waking dreams or castle-building recurring to the mind in this condition, and now believed to have a real existence." Thus, for example, one patient believed in the reality of the good luck previously predicted by a fortune-teller. Other writers on mental disease observe that it is a common thing for the monomaniac to cherish the delusion that he has actually gained the object of some previous ambition, or is undergoing some previously dreaded calamity.

Nor is it necessary to these illusions of memory that there should be any exceptional force of imagination. A fairly vivid representation to ourselves of anything, whether real or fictitious, communicated by others, will often result in something very like a personal recollection. In the case of works of history and fiction, which adopt the narrative tense, this tendency to a subsequent illusion of memory is strengthened by the disposition of the mind at the moment of reading to project itself backwards as in an act of recollection. This is a point which will be further dealt with in the next chapter.

In most cases, however, illusions of memory growing out of previous activities of the imagination appear only after the lapse of some time, when in the natural course of things the mental images derived from actual experience would sink to a certain degree of faintness. Habitual novel-readers often catch themselves mistaking the echo of some passage in a good story for the trace left by an actual event. A person's name, a striking saying, and even an event itself, when we first come across it or experience it, may for a moment seem familiar to us, and to recall some past like impression, if it only happens to resemble something in the works of a favourite novelist. And so, too, any recital of another's experience, whether oral or literary, if it deeply interests us and awakens a specially vivid imagination of the events described, may easily become the starting-point of an illusory recollection.

Children are in the habit of "drinking in" with their vigorous and eager imaginations what is told them and read to them, and hence they are specially likely to fall into this kind of error. Not only so: when they grow up and their early recollections lose their definiteness, becoming a few fragments saved from a lost past, it must pretty certainly happen that if any ideas derived from these recitals are preserved, they will simulate the form of memories. Thus, I have often caught myself for a moment under the sway of the illusion that I actually visited the Exhibition of 1851, the reason being that I am able to recall the descriptions given to me of it by my friends, and the excitement attending their journey to London on the occasion. It is to be added that repetition of the act of imagination will tend still further to deepen the subsequent feeling that we are recollecting something. As Hartley well observes, a man, by repeating a story, easily comes to suppose that he remembers it.[130]

Here, then, we have another source of error that we must take into account in judging of the authenticity of an autobiographical narration of the events of childhood. The more imaginative the writer, the greater the risk of illusion from this source as well as from that of dream-fancies. It is highly probable, indeed, that in such full and explicit records of very early life as those given by Rousseau, by Goethe, or by De Quincey, some part of the quasi-narrative is based on mental images which come floating down the stream of time, not from the substantial world of the writer's personal experience, but from the airy region of dream-land or of waking fancy.

It is to be added that even when the quasi-recollection does answer to a real event of childish history, it may still be an illusion. The fact that others, in narrating events to us, are able to awaken imaginations that afterwards appear as past realities, suggests that much of our supposed early recollection owes its existence to what our parents and friends have from time to time told us respecting the first stages of our history.[131] We see, then, how much uncertainty attaches to all autobiographical description of very early life.

Modern science suggests another possible source of these distinct spectra of memory. May it not happen that, by the law of hereditary transmission, which is now being applied to mental as well as bodily phenomena, ancestral experiences will now and then reflect themselves in our mental life, and so give rise to apparently personal recollections? No one can say that this is not so. When the infant first steadies his eyes on a human face, it may, for aught we know, experience a feeling akin to that described above, when through a survival of dream-fancy we take some new scene to be already familiar. At the age when new emotions rapidly develop themselves, when our hearts are full of wild romantic aspirations, do there not seem to blend with the eager passion of the time deep resonances of a vast and mysterious past, and may not this feeling be a sort of reminiscence of prenatal, that is, ancestral experience?

This idea is certainly a fascinating one, worthy to be a new scientific support for the beautiful thought of Plato and of Wordsworth. But in our present state of knowledge, any reasoning on this supposition would probably appear too fanciful. Some day we may find out how much ancestral experience is capable of bequeathing in this way, whether simply shadowy, undefinable mental tendencies, or something like definite concrete ideas. If, for example, it were found that a child that was descended from a line of seafaring ancestors, and that had never itself seen or heard of the "dark-gleaming sea," manifested a feeling of recognition when first beholding it, we might be pretty sure that such a thing as recollection of prenatal events does take place. But till we have such facts, it seems better to refer the "shadowy recollections" to sources which fall within the individual's own experience.

We may now pass to those hallucinations of memory which are analogous to the _centrally_ excited hallucinations of sense-perception. As I have observed, these are necessarily vague and imperfectly developed.

I have already had occasion to touch on the fact of the vast amount of our forgotten experience. And I observed that forgetfulness was a common negative condition of mnemonic illusion. I have now to complete this statement by the observation that total forgetfulness of any period or stage of our past experience necessarily tends to a vague kind of hallucination. In looking back on the past, we see no absolute gaps in the continuity of our conscious life; our image of this past is essentially one of an unbroken series of conscious experiences. But if through forgetfulness a part of the series is effaced from memory, how, it may be asked, is it possible to construct this perfectly continuous line? The answer is that we fill up such lacunæ vaguely by help of some very imperfectly imagined common type of conscious experience. Just as the eye sees no gap in its field of vision corresponding to the "blind spot" of the retina, but carries its impression over this area, so memory sees no lacuna in the past, but carries its image of conscious life over each of the forgotten spaces.

Sometimes this process of filling in gaps in the past becomes more complete. Thus, for example, in recalling a particular night a week or so ago, I instinctively represent it to myself as so many hours of lying in bed with the waking sensations appropriate to the circumstances, as those of bodily warmth and rest, and of the surrounding silence and darkness.

It is apparent that I cannot conceive myself apart from some mode of conscious experience. In thinking of myself in any part of the past or future in which there is actually no consciousness, or of which the conscious content is quite unknown to me, I necessarily imagine myself as consciously experiencing something. If I picture myself under any definitely conceived circumstances, I irresistibly import into my mental image the feelings appropriate to these surroundings. In this way, people tend to imagine themselves after death as lying in the grave, feeling its darkness and its chilliness. If the circumstances of the time are not distinctly represented, the conception of the conscious experience which constitutes that piece of the ego is necessarily vague, and seems generally to resolve itself into a representation of ourselves as dimly _self-conscious_. What this consciousness of self consists of is a point that will be taken up presently.

_Illusions with respect to Personal Identity._

It would seem to follow from these errors in imaginatively filling up our past life, that our consciousness of personal identity is by no means the simple and exact process which it is commonly supposed to be. I have already remarked that the very fact of there being so large a region of the irrevocable in our past experience proves our consciousness of personal continuity to be largely a matter of inference, or of imaginative conjecture, and not simply of immediate recollection. Indeed, it may be said that our power of ignoring whole regions of the past and of leaping complacently over huge gaps in our memory and linking on conscious experience with conscious experience, involves an illusory sense of continuity, and so far of personal identity. Thus, our ordinary image of our past life, if only by omitting the very large fraction passed in sleep, in at least an approximately unconscious state, clearly contains an ingredient of illusion.[132]

It is to be added that the numerous falsifications of our past history, which our retrospective imagination is capable of perpetrating, make our representation of ourselves at different moments and in different stages of our past history to a considerable extent illusory. Thus, though to mistake a past dream-experience for a waking one may not be to lose or confuse the sense of identity, since our dreams are, after all, a part of our experience, yet to imagine that we have ourselves seen what we have only heard from another or read is clearly to confuse the boundaries of our identity. And with respect to longer sections of our history, it is plain that when we wrongly assimilate our remote to our present self, and clothe our childish nature with the feelings and the ideas of our adult life, we identify ourselves overmuch. In this way, through the corruption of our memory, a kind of sham self gets mixed up with the real self, so that we cannot, strictly speaking, be sure that when we project a mnemonic image into the remote past we are not really running away from our true personality.

So far I have been touching only on slight errors in the recognition of that identical self which is represented as persisting through all the fluctuations of conscious life. Other and grosser illusions connected with personal identity are also found to be closely related to defects or disturbances of the ordinary mnemonic process, and so can be best treated here. In order to understand these, we must inquire a little into the nature of our idea and consciousness of a persistent self. Here, again, I would remind the reader that I am treating the point only so far as it can be treated scientifically or empirically, that is to say, by examining what concrete facts or data of experience are taken up into the idea of self. I do not wish to foreclose the philosophic question whether anything more than this empirical content is involved in the conception.

My idea of myself as persisting appears to be built up of certain similarities in the succession of my experiences. Thus, my permanent self consists, on the bodily side, of a continually renewable perception of my own organism, which perception is mainly visual and tactual, and which remains pretty constant within certain limits of time. With this objective similarity is closely conjoined a subjective similarity. Thus, the same sensibilities continue to characterize the various parts of my organism. Similarly, there are the higher intellectual, emotional, and moral peculiarities and dispositions. My idea of my persistent self is essentially a collective image representing a relatively unchanging material object, endowed with unchanging sensibilities and forming a kind of support for permanent higher mental attributes.

The construction of this idea of an enduring unchanging ego is rendered very much easier by the fact that certain concrete feelings are approximately constant elements in our mental life. Among these must be ranked first that dimly discriminated mass of organic sensation which in average states of health is fairly constant, and which stands in sharp contrast to the fluctuating external sensations. These feelings enter into and profoundly colour each person's mental image of himself. In addition to this, there are the frequently recurring higher feelings, the dominant passions and ideas which approximate more or less closely to constant factors of our conscious experience.

This total image of the ego becomes defined and rendered precise by a number of distinctions, as that between my own body or that particular material object with which are intimately united all my feelings, and other material objects in general; then between my organism and other human organisms, with which I learn to connect certain feelings answering to my own, but only faintly represented instead of actually realized feelings. To these prime distinctions are added others, hardly less fundamental, as those between my individual bodily appearance and that of other living bodies, between my personal and characteristic modes of feeling and thinking and those of others, and so on.

Our sense of personal identity may be said to be rooted in that special side of the mnemonic process which consists in the linking of all sequent events together by means of a thread of common consciousness. It is closely connected with that smooth, gliding movement of imagination which appears to involve some more or less distinct consciousness of the uniting thread of similarity. And so long as this movement is possible, so long, that is to say, as retrospective imagination detects the common element, which we may specifically call the recurring consciousness of self, so long is there the undisturbed assurance of personal identity. Nay, more, even when such a recognition might seem to be difficult, if not impossible, as in linking together the very unlike selves, viewed both on their objective and subjective sides, of childhood, youth, and mature life, the mind manages, as we have seen, to feign to itself a sufficient amount of such similarity.

But this process of linking stage to stage, of discerning the common or the recurring amid the changing and the evanescent, has its limits. Every great and sudden change in our experience tends, momentarily at least, to hinder the smooth reflux of imagination. It makes too sharp a break in our conscious life, so that imagination is incapable of spanning the gap and realizing the then and the now as parts of a connected continuous tissue.[133]

These changes may be either objective or subjective. Any sudden alteration of our bodily appearance sensibly impedes the movement of imagination. A patient after a fever, when he first looks in the glass, exclaims, "I don't know myself." More commonly the bodily changes which affect the consciousness of an enduring self are such as involve considerable alterations of coenæsthesis, or the mass of stable organic sensation. Thus, the loss of a limb, by cutting off a portion of the old sensations through which the organism may be said to be immediately felt, and by introducing new and unfamiliar feelings, will distinctly give a shock to our consciousness of self.

Purely subjective changes, too, or, to speak correctly, such as are known subjectively only, will suffice to disturb the sense of personal unity. Any great moral shock, involving something like a revolution in our recurring emotional experience, seems at the moment to rupture the bond of identity. And even some time after, as I have already remarked, such cataclysms in our mental geology lead to the imaginative thrusting of the old personality away from the new one under the form of a "dead self."[134]

We see, then, that the failure of our ordinary assurance of personal identity is due to the recognition of difference without similarity. It arises from an act of memory--for the mind must still be able to recall the past, dimly at least--but from a memory which misses its habitual support in a recognized element of constancy. If there is no memory, that is to say, if the past is a complete blank, the mind simply feels a rupture of identity without any transformation of self. This is our condition on awaking from a perfectly forgotten period of sleep, or from a perfectly unconscious state (if such is possible) when induced by anæsthetics. Such gaps are, as we have seen, easily filled up, and the sense of identity restored by a kind of retrospective "skipping." On the other hand, the confusion which arises from too great and violent a transformation of our _remembered_ experiences is much less easily corrected. As long as the recollection of the old feelings remains, and with this the sense of violent contrast between the old and the new ones, so long will the illusion of two sundered selves tend to recur.

The full development of this process of imaginative fission or cleavage of self is to be met with in mental disease. The beginnings of such disease, accompanied as they commonly are with disturbances of bodily sensations and the recurring emotions, illustrate in a very interesting way the dependence of the recognition of self on a certain degree of uniformity in the contents of consciousness. The patient, when first aware of these changes, is perplexed, and often regards the new feelings as making up another self, a foreign _Tu_, as distinguished from the familiar _Ego_. And sometimes he expresses the relation between the old and the new self in fantastic ways, as when he imagines the former to be under the power of some foreign personality.

When the change is complete, the patient is apt to think of his former self as detached from his present, and of his previous life as a kind of unreal dream; and this fading away of the past into shadowy unreal forms has, as its result, a curious aberration in the sense of time. Thus, it is said that a patient, after being in an asylum only one day, will declare that he has been there a year, five years, and even ten years.[135] This confusion as to self naturally becomes the starting-point of illusions of perception; the transformation of self seeming to require as its logical correlative (for there is a crude logic even in mental disease) a transformation of the environment. When the disease is fully developed under the particular form of monomania, the recollection of the former normal self commonly disappears altogether, or fades away into a dim image of some perfectly separate personality. A new ego is now fully substituted for the old. In other and more violent forms of disease (dementia) the power of connecting the past and present may disappear altogether, and nothing but the _disjecta membra_ of an ego remain.

* * * * *

Enough has, perhaps, been said to show how much of uncertainty and of self-deception enters into the processes of memory. This much-esteemed faculty, valuable and indispensable though it certainly is, can clearly lay no claim to that absolute infallibility which is sometimes said to belong to it. Our individual recollection, left to itself, is liable to a number of illusions even with regard to fairly recent events, and in the case of remote ones it may be said to err habitually and uniformly in a greater or less degree. To speak plainly, we can never be certain on the ground of our personal recollection alone that a distant event happened exactly in the way and at the time that we suppose. Nor does there seem to be any simple way by mere reflection on the contents of our memory of distinguishing what kinds of recollection are likely to be illusory.

How, then, it may be asked, can we ever be certain that we are faithfully recalling the actual events of the past? Given a fairly good, that is, a cultivated memory, it may be said that in the case of very recent events a man may feel certain that, when the conditions of careful attention at the time to what really happened were present, a distinct recollection is substantially correct. Also it is obvious that with respect to all repeated experiences our memories afford practically safe guides. When memory becomes the basis of some item of generalized knowledge, as, for example, of the truth that the pain of indigestion has followed a too copious indulgence in rich food, there is little room for an error of memory properly so called. On the other hand, when an event is not repeated in our experience, but forms a unique link in our personal history, the chances of error increase with the distance of the event; and here the best of us will do well to have resort to a process of verification or, if necessary, of correction.

In order thus to verify the utterances of memory, we must look beyond our own internal mental states to some external facts. Thus, the recollections of our early life may often be tested by letters written by ourselves or our friends at the time, by diaries, and so on. When there is no unerring objective record to be found, we may have recourse to the less satisfactory method of comparing our recollections with those of others. By so doing we may reach a rough average recollection which shall at least be free from any individual error corresponding to that of personal equation in perception. But even thus we cannot be sure of eliminating all error, since there may be a cause of illusion acting on all our minds alike, as, for example, the extraordinary nature of the occurrence, which would pretty certainly lead to a common exaggeration of its magnitude, etc., and since, moreover, this process of comparing recollections affords an opportunity for that reading back a present preconception into the past to which reference has already been made.

The result of our inquiry is less alarming than it looks at first sight. Knowledge is valuable for action, and error is chiefly hurtful in so far as it misdirects conduct. Now, in a general way, we do not need to act upon a recollection of single remote events; our conduct is sufficiently shaped by an accurate recollection of single recent events, together with those bundles of recollections of recurring events and sequences of events which constitute our knowledge of ourselves and our common knowledge of the world about us. Nature has done commendably well in endowing us with the means of cultivating our memories up to this point, and we ought not to blame her for not giving us powers which would only very rarely prove of any appreciable practical service to us.

NOTE.

MOMENTARY ILLUSIONS OF SELF-CONSCIOUSNESS.

The account of the apparent ruptures in our personal identity given in this chapter may help us to understand the strange tendency to confuse self with other objects which occasionally appears in waking consciousness and in dreams. These errors may be said generally to be due to the breaking up of the composite image of self into its fragments, and the regarding of certain of these only. Thus, the momentary occurrence of partial illusion in intense sympathy with others, including that imaginative projection of self into inanimate objects, to which reference has already been made, may be said to depend on exclusive attention to the subjective aspect of self, to the total disregard of the objective aspect. In other words, when we thus momentarily "lose ourselves," or merge our own existence in that of another object, we clearly let drop out of sight the visual representation of our own individual organism. On the other hand, when in dreams we double our personality, or represent to ourselves an external self which becomes the object of visual perception, it is probably because we isolate in imagination the objective aspect of our personality from the other and subjective aspect. It is not at all unlikely that the several confusions of self touched on in this chapter have had something to do with the genesis of the various historical theories of a transformed existence, as, for example, the celebrated doctrine of metempsychosis.