Autobiographical note 3 страница

¹ [Footnote added 1909:] Subsequent experience leads me to add that it by no means rarely happens that innocent and unimportant actions of the previous day are repeated in a dream: such, for instance, as packing a trunk, preparing food in the kitchen, and so on. What the dreamer is himself stressing in dreams of this kind is not, however, the content of the memory but the fact of its being ‘real’: ‘I really did do all that yesterday.’

(C)

THE STIMULI AND SOURCES OF DREAMS

There is a popular saying that ‘dreams come from indigestion’ and this helps us to see what is meant by the stimuli and sources of dreams. Behind these concepts lies a theory according to which dreams are a result of a disturbance of sleep: we should not have had a dream unless something disturbing had happened during our sleep, and the dream was a reaction to that disturbance.

Discussions upon the exciting causes of dreams occupy a very large space in the literature of the subject. The problem could obviously only arise after dreams had become a subject of biological investigation. The ancients, who believed that dreams were inspired by the gods, had no need to look around for their stimulus: dreams emanated from the will of divine or daemonic powers and their content arose from the knowledge or purpose of those powers. Science was immediately faced by the question of whether the stimulus to dreaming was always the same or whether there could be many kinds of such stimuli; and this involved the consideration of whether the explanation of the causation of dreams fell within the province of psychology or rather of physiology. Most authorities seem to agree in assuming that the causes that disturb sleep - that is, the sources of dreaming - may be of many kinds and that somatic stimuli and mental excitations alike may come to act as instigators of dreams. Opinions differ widely, however, in the preference they show for one or the other source of dreams and in the order of importance which they assign to them as factors in the production of dreams.

Any complete enumeration of the sources of dreams leads to a recognition of four kinds of source; and these have also been used for the classification of dreams themselves. They are: (1) external (objective) sensory excitations; (2) internal (subjective) sensory excitations; (3) internal (organic) somatic stimuli; and (4) purely psychical sources of stimulation. 1. EXTERNAL SENSORY STIMULI

The younger Strümpell, the son of the philosopher whose book on dreams has already given us several hints upon their problems, published a well-known account of his observations upon one of his patients who was afflicted with general anaesthesia of the surface of his body and paralysis of several of his higher sense organs. If the few of this man’s sensory channels which remained open to the external world were closed, he would fall asleep. Now when we ourselves wish to go to sleep we are in the habit of trying to produce a situation similar to that of Strümpell’s experiment. We close our most important sensory channels, our eyes, and try to protect the other senses from all stimuli or from any modification of the stimuli acting on them. We then fall asleep, even though our plan is never completely realized. We cannot keep stimuli completely away from our sense organs nor can we completely suspend the excitability of our sense organs. The fact that a fairly powerful stimulus will awaken us at any time is evidence that ‘even in sleep the soul is in constant contact with the extracorporeal world’. The sensory stimuli that reach us during sleep may very well become sources of dreams.

Now there are a great number of such stimuli, ranging from the unavoidable ones which the state of sleep itself necessarily involves or must tolerate from time to time, to the accidental, rousing stimuli which may or do put an end to sleep. A bright light may force its way into our eyes, or a noise may make itself heard, or some strong-smelling substance may stimulate the mucous membrane of our nose. By unintentional movements during our sleep we may uncover some part of our body and expose it to sensations of chill, or by a change in posture we may ourselves bring about sensations of pressure or contact. We may be stung by a gnat, or some small mishap during the night may impinge upon several of our senses at once. Attentive observers have collected a whole series of dreams in which there has been such a far-reaching correspondence between a stimulus noticed on waking and a portion of the content of the dream that it has been possible to identify the stimulus as the source of the dream.

I will quote from Jessen (1855, 527 f.) a collection of dreams of this kind which may be traced back to objective, and more or less accidental, sensory stimulation.

‘Every noise that is indistinctly perceived arouses corresponding dream-images. A peal of thunder will set us in the midst of a battle; the crowing of a cock may turn into a man’s cry of terror; the creaking of a door may produce a dream of burglars. If our bed-clothes fall off in the night, we may dream, perhaps, of walking about naked or of falling into water. If we are lying cross-wise in bed and push our feet over the edge, we may dream that we are standing on the brink of a frightful precipice or that we are falling over a cliff. If our head happens to get under the pillow, we dream of being beneath a huge overhanging rock which is on the point of burying us under its weight. Accumulations of semen lead to lascivious dreams, local pains produce ideas of being ill-treated, attacked or injured....’

‘Meier (1758, 33) once dreamt that he was overpowered by some men who stretched him out on his back on the ground and drove a stake into the earth between his big toe and the next one. While he was imagining this in the dream he woke up and found that a straw was sticking between his toes. On another occasion, according to Hennings (1784, 258), when Meier had fastened his shirt rather tight round his neck, he dreamt that he was being hanged. Hoffbauer dreamt when he was a young man of falling down from a high wall, and when he woke up found that his bedstead had collapsed and that he had really fallen on to the floor.... Gregory reports that once, when he was lying with his feet on a hot-water bottle, he dreamt he had climbed to the top of Mount Etna and that the ground there was intolerably hot. Another man, who was sleeping with a hot poultice on his head, dreamt that he was being scalped by a band of Red Indians; while a third, who was wearing a damp night-shirt, imagined that he was being dragged through a stream. An attack of gout that came on suddenly during sleep caused the patient to believe he was in the hands of the Inquisition and being tortured on the rack. (Macnish.)'

The argument based on the similarity between the stimulus and the content of the dream gains in strength if it is possible deliberately to convey a sensory stimulus to the sleeper and produce in him a dream corresponding to that stimulus. According to Macnish (loc. cit.), quoted by Jessen (1855, 529), experiments of this sort had already been made by Girou de Buzareingues. ‘He left his knee uncovered and dreamt that he was travelling at night in a mail coach. He remarks upon this that travellers will no doubt be aware how cold one’s knees become at night in a coach. Another time he left his head uncovered at the back and dreamt that he was taking part in a religious ceremony in the open air. It must be explained that in the country in which he lived it was the custom always to keep the head covered except in circumstances such as these.’

Maury (1878) brings forward some new observations of dreams produced in himself. (A number of other experiments were unsuccessful.)

(1) His lips and the tip of his nose were tickled with a feather. - He dreamt of a frightful form of torture: a mask made of pitch was placed on his face and then pulled off, so that it took his skin off with it,

(2) A pair of scissors was sharpened on a pair of pliers. -He heard bells pealing, followed by alarm-bells, and he was back in the June days of 1848.

(3) He was given some eau-de-cologne to smell. -He was in Cairo, in Johann Maria Farina’s shop. Some absurd adventures followed, which he could not reproduce.

(4) He was pinched lightly on the neck. - He dreamt he was being given a mustard plaster and thought of the doctor who had treated him as a child.

(5) A hot iron was brought close to his face. - He dreamt that the ‘chauffeurs’¹ had made their way into the house and were forcing its inhabitants to give up their money by sticking their feet into braziers of hot coal. The Duchess of Abrantes, whose secretary he was in the dream, then appeared.

(8) A drop of water was dropped on his forehead. - He was in Italy, was sweating violently and was drinking white Orvieto wine.

(9) Light from a candle was repeatedly shone upon him through a sheet of red paper. - He dreamt of the weather and of the heat, and was once again in a storm he had experienced in the English Channel.

¹ The ‘chauffeurs’ were bands of robbers in La Vendée, who made use of the method of torture described above.

Other attempts at producing dreams experimentally have been reported by Hervey de Saint-Denys, Weygandt (1893), and others.

Many writers have commented upon ‘the striking facility with which dreams are able to weave a sudden impression from the world of the senses into their own structure so that it comes as what appears to be a pre-arranged catastrophe that his been gradually led up to.’ (Hildebrandt, 1875,.) ‘In my youth’, the author goes on, ‘I used to make use of an alarm-clock in order to be up regularly at a fixed hour. It must have happened hundreds of times that the noise produced by this instrument fitted into an ostensibly lengthy and connected dream as though the whole dream had been leading up to that one event and had reached its appointed end in what was a logically indispensable climax.’

I shall quote three of these alarm-clock dreams presently in another connection.

Volkelt (1875, 108 f.) writes: ‘A composer once dreamt that he was giving a class and was trying to make a point clear to his pupils. When he had done, he turned to one of the boys and asked him if he had followed. The boy shouted back like a lunatic: "Oh ja! " He began to reprove the boy angrily for shouting, but the whole class broke out into cries first of "Orja!", then of "Eurjo!" and finally of "Feuerjo!" At this point he was woken up by actual cries of "Feuerjo!" in the street.’

Garnier (1865) tells how Napoleon I was woken by a bomb-explosion while he was asleep in his carriage. He had a dream that he was once more crossing the Tagliamento under the Austrian bombardment, and at last started up with a cry: ‘We are undermined!’

A dream dreamt by Maury (1878, 161) has become famous. He was ill and lying in his room in bed, with his mother sitting beside him, and dreamt that it was during the Reign of Terror. After witnessing a number of frightful scenes of murder, he was finally himself brought before the revolutionary tribunal. There he saw Robespierre, Marat, Fouquier-Tinville and the rest of the grim heroes of those terrible days. He was questioned by them, and, after a number of incidents which were not retained in his memory, was condemned, and led to the place of execution surrounded by an immense mob. He climbed on to the scaffold and was bound to the plank by the executioner. It was tipped up. The blade of the guillotine fell. He felt his head being separated from his body, woke up in extreme anxiety and found that the top of the bed had fallen down and had struck his cervical vertebrae just in the way in which the blade of the guillotine would actually have struck them.

This dream was the basis of an interesting discussion between Le Lorrain (1894) and Egger (1895) in the Revue philosophique. The question raised was whether and how it was possible for a dreamer to compress such an apparently superabundant quantity of material into the short period elapsing between his perceiving the rousing stimulus and his waking.

Examples of this kind leave an impression that of all the sources of dreams the best confirmed are objective sensory stimuli during sleep. Moreover they are the only sources whatever taken into account by laymen. If an educated man, who is unacquainted with the literature of dreams, is asked how dreams arise, he will infallibly answer with a reference to some instance he has come across in which a dream was explained by an objective sensory stimulus discovered after waking. Scientific enquiry, however, cannot stop there. It finds an occasion for further questions in the observed fact that the stimulus which impinges on the senses during sleep does not appear in the dream in its real shape but is replaced by another image in some way related to it. But the relation connecting the stimulus of the dream to the dream which is its result is, to quote Maury’s words (1854, 72); ‘une affinité quelconque, mais qui n’est pas unique et exclusive.’ ¹ Let us consider in this connection three of Hildebrandt’s alarm-clock dreams (1875, 37 f.). The question they raise is why the same stimulus should have provoked three such different dreams and why it should have provoked these rather than any other.

¹ [‘An affinity of some kind, but one which is not unique and exclusive.’]

‘I dreamt, then, that one spring morning I was going for a walk and was strolling through the green fields till I came to a neighbouring village, where I saw the villagers in their best clothes, with hymn-books under their arms, flocking to the church. Of course! It was Sunday, and early morning service would soon be beginning. I decided I would attend it; but first, as I was rather hot from walking, I went into the churchyard which surrounded the church, to cool down. While I was reading some of the tombstones, I heard the bell-ringer climbing up the church tower and at the top of it I now saw the little village bell which would presently give the signal for the beginning of devotions. For quite a while it hung there motionless, then it began to swing, and suddenly its peal began to ring out clear and piercing - so clear and piercing that it put an end to my sleep. But what was ringing was the alarm-clock.

‘Here is another instance. It was a bright winter’s day and the streets were covered with deep snow. I had agreed to join a party for a sleigh-ride; but I had to wait a long time before news came that the sleigh was at the door. Now followed the preparations for getting in - the fur rug spread out, the foot muff put ready- and at last I was sitting in my seat. But even then the moment of departure was delayed till a pull at the reins gave the waiting horses the signal. Then off they started, and, with a violent shake, the sleigh bells broke into their familiar jingle - with such violence, in fact, that in a moment the cobweb of my dream was torn through. And once again it was only the shrill sound of the alarm-clock.

‘And now yet a third example. I saw a kitchen-maid, carrying several dozen plates piled on one another, walking along the passage to the dining-room. The column of china in her arms seemed to me in danger of losing its balance. "Take care," I exclaimed, "or you’ll drop the whole load." The inevitable rejoinder duly followed: she was quite accustomed to that kind of job, and so on. And meanwhile my anxious looks followed the advancing figure. Then - just as I expected -she stumbled at the threshold and the fragile crockery slipped and rattled and clattered in a hundred pieces on the floor. But the noise continued without ceasing, and soon it seemed no longer to be a clattering; it was turning into a ringing - and the ringing, as my waking self now became aware, was only the alarm-clock doing its duty.’

The question of why the mind mistakes the nature of objective sensory stimuli in dreams receives almost the same answer from Strümpell (1877) as from Wundt (1874): the mind receives stimuli that reach it during sleep under conditions favourable to the formation of illusions. A sense impression is recognized by us and correctly interpreted - that is, it is placed in the group of memories to which, in accordance with all our previous experiences, it belongs - provided the impression is sufficiently strong, clear and lasting and provided we have sufficient time at our disposal for considering the matter. If these conditions are not fulfilled, we mistake the object which is the source of the impression: we form an illusion about it. ‘If someone goes for a walk in the open country and has in indeterminate perception of a distant object, he may at first believe it to be a horse.’ On a closer view he may be led to interpret it as a cow lying down, and the image may finally resolve itself definitely into a group of people sitting on the ground. The impressions received by the mind from external stimuli during sleep are of a similarly indeterminate nature; and on their basis the mind forms illusions, since a greater or smaller number of mnemic images are aroused by the impression and it is through them that it acquires its psychical value. From which of the many groups of memories concerned the related images shall be aroused and which of the possible associative connections shall accordingly be put into action - these questions too, on Strümpell’s theory, are indeterminable and are, as it were, left open to the arbitrary decision of the mind.

At this point we are faced with a choice between two alternatives. We may admit it as a fact that it is impossible to follow the laws governing the formation of dreams any further; and we may accordingly refrain from enquiring whether there may not be other determinants governing the interpretation put by the dreamer upon the illusion called up by the sense-impression. Or, on the other hand, we may have a suspicion that the sensory stimulus which impinges on the sleeper plays only a modest part in generating his dream and that other factors determine the choice of the mnemic images which are to be aroused in him. In fact, if we examine Maury’s experimentally produced dreams (which I have related in such detail for this very reason), we shall be tempted to say that the experiment in fact accounts for the origin of only one element of the dreams; the rest of their content seems too self-contained, too definite in its details, to be explicable solely by the necessity for fitting in with the element experimentally introduced from outside. Indeed, one begins to have doubts about the illusion theory and about the power of objective impressions to give a shape to dreams when one finds that those impressions are sometimes subjected in dreams to the most peculiar and far-fetched interpretations. Thus Simon (1888) tells us of a dream in which he saw some gigantic figures seated at table and clearly heard the frightful snapping noise made by their jaws coming together as they chewed. When he awoke he heard the beat of a horse’s hooves galloping past his window. The noise made by the horse’s hooves may have suggested ideas from a group of memories connected with Gulliver’s Travels - the giants of Brobdingnag and the virtuous Houyhnhnms - if I may venture on an interpretation without the dreamer’s assistance. Is it not probable, then, that the choice of such an unusual group of memories as these was facilitated by motives other than the objective stimulus alone!¹

¹ [Footnote added 1911:] The appearance of gigantic figures in a dream gives grounds for supposing that some scene from the dreamer’s childhood is involved. - [Added 1925:] Incidentally, the interpretation given in the text, pointing to a reminiscence of Gulliver’s Travels, is a good example of what an interpretation ought not to be. The interpreter of a dream should not give free play to his own ingenuity and neglect the dreamer’s associations.

2. INTERNAL (SUBJECTIVE) SENSORY EXCITATIONS

In spite of any objections to the contrary, it has to be admitted that the part played by objective sensory excitations during sleep in provoking dreams remains indisputable. And if such stimuli may appear, from their nature and frequency, insufficient to explain every dream-image, we shall be encouraged to seek for other sources of dreams analogous to them in their operation. I cannot say when the idea first cropped up of taking internal (subjective) excitations of the sense organs into account alongside of the external sensory stimuli. It is, however, the case that this is done, more or less explicitly, in all the more recent discussions of the aetiology of dreams. ‘An essential part is also played, I believe’, writes Wundt (1874, 657), ‘in the production of the illusions that occur in dreams by the subjective visual and auditory sensations which are familiar to us in the waking state as the formless areas of luminosity which become visible to us when our field of vision is darkened, as ringing or buzzing in the ears, and so on. Especially important among these are the subjective excitations of the retina. It is in this way that is to be explained the remarkable tendency of dreams to conjure up before the eyes similar or identical objects in large numbers. We see before us innumerable birds or butterflies or fishes or coloured beads or flowers, etc. Here the luminous dust in the darkened field of vision has taken on a fantastic shape, and the numerous specks of which it consists are incorporated into the dream as an equal number of separate images; and these, on account of their mobility, are regarded as moving objects. -This is no doubt also the basis of the great fondness shown by dreams for animal figures of every sort; for the immense variety of such forms can adjust itself easily to the particular form assumed by the subjective luminous images.’

As sources of dream-images, subjective sensory excitations have the obvious advantage of not being dependent, like objective ones, upon external chance. They are ready to hand, as one might say, whenever they are needed as an explanation. But they are at a disadvantage compared with objective sensory stimuli in that the part they play in instigating a dream is scarcely or not at all open to confirmation, as is the case with objective stimuli, by observation and experiment. The chief evidence in favour of the power of subjective sensory excitations to instigate dreams is provided by what are known as ‘hypnagogic hallucinations’, or, to use Johannes Müller’s term (1826), ‘imaginative visual phenomena’. These are images, often very vivid and rapidly changing, which are apt to appear - quite habitually, in some people - during the period of falling asleep; and they may also persist for a time after the eyes have been opened. Maury, who was subject to them in a high degree, has made an exhaustive examination of them and maintains (as did Müller before him) their connection and indeed their identity with dream-images. In order to produce them, he says (Maury, 1878, 59 f.), a certain amount of mental passivity, a relaxation of the strain of attention, is necessary. It is enough, however, to fall into a lethargic state of this kind for no more than a second (provided that one has the necessary predisposition) in order to have a hypnagogic hallucination. After this one may perhaps wake up again and the process may be repeated several times until one finally falls asleep. Maury found that if he then woke up once more after not too long an interval, he was able to detect in his dream the same images that had floated before his eyes as hypnagogic hallucinations before he fell asleep. (Ibid., 134 f.) This was the case on one occasion with a number of grotesque figures with distorted faces and strange coiffures which pestered him with extreme pertinacity while he was going to sleep and which he remembered having dreamt about after he woke. Another time, when he was suffering from hunger owing to having put himself on a light diet, he had a hypnagogic vision of a plate and a hand armed with a fork which was helping itself to some of the food from the plate. In the dream which followed he was sitting at a well spread table and heard the noise made by the diners with their forks. Yet another time, when he went to sleep with his eyes in an irritated and painful state, he had a hypnagogic hallucination of some microscopically small signs which he could only decipher one by one with the greatest difficulty; he was woken from his sleep an hour later and remembered a dream in which here was an open book printed in very small type which he was reading painfully.

Auditory hallucinations of words, names, and so on can also occur hypnagogically in the same way as visual images, and may then be repeated in a dream - just as an overture announces the principal themes which are to be heard in the opera that is to follow.

A more recent observer of hypnagogic hallucinations, G. Trumbull Ladd (1892), has followed the same lines as Müller and Maury. After some practice he succeeded in being able to wake himself suddenly without opening his eyes, from two to five minutes after gradually falling asleep. He thus had an opportunity of comparing the retinal sensations which were just disappearing with the dream-images persisting in his memory. He declares that it was possible in every case to recognize an internal relation between the two, for the luminous points and lines of the idioretinal light provided, as it were, an outline drawing or diagram of the figures mentally perceived in the dream. For instance, an arrangement of the luminous points in the retina in parallel lines corresponded to a dream in which he had been seeing, clearly spread out in front of him, some lines of print which he was engaged in reading. Or, to use his own words, ‘the clearly printed page which I was reading in my dream faded away into an object that appeared to my waking consciousness like a section of an actual page of print when seen through an oval hole in a piece of paper at too great a distance to distinguish more than an occasional fragment of a word, and even that dimly.’ Ladd is of opinion (though he does not underestimate the part played in the phenomenon by central factors) that scarcely a single visual dream, occurs without the participation of material provided by intraocular retinal excitation. This applies especially to dreams occurring soon after falling asleep in a dark room, while the source of stimulus for dreams occurring in the morning shortly before waking is the objective light which penetrates the eyes in a room that is growing light. The changing, perpetually shifting character of the excitation of the idioretinal light corresponds precisely to the constantly moving succession of images shown us by our dreams. No one who attaches importance to these observations of Ladd’s will underestimate the part played in dreams by these subjective sources of stimulation, for, as we know, visual images constitute the principal component of our dreams. The contributions from the other senses, except for that of hearing, are intermittent and of less importance.

3. INTERNAL ORGANIC SOMATIC STIMULI

Since we are now engaged in looking for sources of dreams inside the organism instead of outside it, we must bear in mind that almost all our internal organs, though they give us scarcely any news of their working so long as they are in a healthy state, become a source of what are mainly distressing sensations when they are in what we describe as states of excitation, or during illnesses. These sensations must be equated with the sensory or painful stimuli reaching us from the outside. The experience of ages is reflected in - to take an example - Strümpell’s remarks on the subject (1877, 107): ‘During sleep the mind attains a far deeper and wider sensory consciousness of somatic events than during the waking state. It is obliged to receive and be affected by impressions of stimuli from parts of the body and from changes in the body of which it knows nothing when awake.’ So early a writer as Aristotle regarded it as quite possible that the beginnings of an illness might make themselves felt in dreams before anything could be noticed of it in waking life, owing to the magnifying effect produced upon impressions by dreams. (See above, p. 518.) Medical writers, too, who were certainly far from believing in the prophetic power of dreams, have not disputed their significance as premonitors of illness. (Cf. Simon, 1888, 31, and many earlier writers.)¹

¹ [Footnote added 1914:] Apart from the diagnostic value ascribed to dreams (e.g. in the works of Hippocrates), their therapeutic importance in antiquity must also be borne in mind. In Greece there were dream oracles, which were regularly visited by patients in search of recovery. A sick man would enter the temple of Apollo or Aesculapius, would perform various ceremonies there, would be purified by lustration, massage and incense, and then, in a state of exaltation, would be stretched on the skin of a ram that had been sacrificed. He would then fall asleep and would dream of the remedies for his illness. These would be revealed to him either in their natural form or in symbols and pictures which would afterwards be interpreted by the priests. For further information upon therapeutic dreams among the Greeks see Lehmann (1908, 1, 74), Bouché-Leclercq (1879-1882), Hermann (1858, §41, 262 ff., and 1882, §38, 356), Böttinger (1795, 163 ff.), Lloyd (1877), Döllinger (1857, 130).

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