The Interpretation of Dreams by Sigmund Freud
1. External sensory stimuli

The younger Strumpell, the son of the philosopher, whose work on dreams has already more than once served us as a guide in considering the problems of dreams, has, as is well known, recorded his observations of a patient afflicted with general anaesthesia of the skin and with paralysis of several of the higher sensory organs. This man would laps into sleep whenever the few remaining sensory paths between himself and the outer world were closed. When we wish to fall asleep we are accustomed to strive for a condition similar to that obtaining in Strumpell's experiment. We close the most important sensory portals, the eyes, and we endeavour to protect the other senses from all stimuli or from any change of the stimuli already acting upon them. We then fall asleep, although our preparations are never wholly successful. For we can never completely insulate the sensory organs, nor can we entirely abolish the excitability of the sensory organs themselves. That we may at any time be awakened by intenser stimuli should prove to us "that the mind has remained in constant communication with the external world even during sleep." The sensory stimuli that reach us during sleep may easily become the source of dreams.

There are a great many stimuli of this nature, ranging from those unavoidable stimuli which are proper to the state of sleep or occasionally admitted by it, to those fortuitous stimuli which are calculated to wake the sleeper. Thus a strong light may fall upon the eyes, a noise may be heard, or an odour may irritate the mucous membranes of the nose. In our unintentional movements during sleep we may lay bare parts of the body, and thus expose them to a sensation of cold, or by a change of position we may excite sensations of pressure and touch. A mosquito may bite us, or a slight nocturnal mischance may simultaneously attack more than one sense- organ. Observers have called attention to a whole series of dreams in which the stimulus ascertained on waking and some part of the dream-content corresponded to such a degree that the stimulus could be recognized as the source of the dream.

I shall here cite a number of such dreams, collected by Jessen (p. 527), which are traceable to more or less accidental objective sensory stimuli. Every noise indistinctly perceived gives rise to corresponding dream- representations; the rolling of thunder takes us into the thick of battle, the crowing of a cock may be transformed into human shrieks of terror, and the creaking of a door may conjure up dreams of burglars breaking into the house. When one of our blankets slips off us at night we may dream that we are walking about naked, or falling into water. If we lie diagonally across the bed with our feet extending beyond the edge, we may dream of standing on the brink of a terrifying precipice, or of falling from a great height. Should our head accidentally get under the pillow we may imagine a huge rock overhanging us and about to crush us under its weight. An accumulation of semen produces voluptuous dreams, and local pains give rise to ideas of suffering ill-treatment, of hostile attacks, or of accidental bodily injuries....

"Meier (Versuch einer Erklarung des Nachtwandelns, Halle, 1758, p. 33) once dreamed of being attacked by several men who threw him flat on the ground and drove a stake into the earth between his first and second toes. While imagining this in his dream he suddenly awoke and felt a piece of straw sticking between his toes. The same author, according to Hemmings (Von den Traumen und Nachtwandlern, Weimar, 1784, p. 258), "dreamed on another occasion, when his nightshirt was rather too tight round his neck, that he was being hanged. In his youth Hoffbauer dreamed of having fallen from a high wall, and found, on waking, that the bedstead had come apart, and that he had actually fallen on to the floor.... Gregory relates that he once applied a hot-water bottle to his feet, and dreamed of taking a trip to the summit of Mount Etna, where he found the heat of the soil almost unbearable. After having a blister applied to his head, another man dreamed of being scalped by Indians; still another, whose shirt was damp, dreamed that he was dragged through a stream. An attack of gout caused a patient to believe that he was in the hands of the Inquisition, and suffering the pains of torture (Macnish)."

The argument that there is a resemblance between the dream-stimulus and the dream-content would be confirmed if, by a systematic induction of stimuli, we should succeed in producing dreams corresponding to these stimuli. According to Macnish such experiments had already been made by Giron de Buzareingues. "He left his knee exposed and dreamed of travelling on a mail- coach by night. He remarked, in this connection, that travellers were well aware how cold the knees become in a coach at night. On another occasion he left the back of his head uncovered, and dreamed that he was taking part in a religious ceremony in the open air. In the country where he lived it was customary to keep the head always covered except on occasions of this kind."

Maury reports fresh observation on self-induced dreams of his own. (A number of other experiments were unsuccessful.)

1. He was tickled with a feather on his lips and on the tip of his nose. He dreamed of an awful torture, viz., that a mask of pitch was stuck to his face and then forcibly torn off, bringing the skin with it.

2. Scissors were whetted against a pair of tweezers. He heard bells ringing, then sounds of tumult which took him back to the days of the Revolution of 1848.

3. Eau de Cologne was held to his nostrils. He found himself in Cairo, in the shop of Johann Maria Farina. This was followed by fantastic adventures which he was not able to recall.

4. His neck was lightly pinched. He dreamed that a blister was being applied, and thought of a doctor who had treated him in childhood.

5. A hot iron was brought near his face. He dreamed that chauffeurs * had broken into the house, and were forcing the occupants to give up their money by thrusting their feet into braziers. The Duchesse d'Abrantes, whose secretary he imagined himself to be then entered the room.

* Chauffeurs were bands of robbers in the Vendee who resorted to this form of torture.

6. A drop of water was allowed to fall on to his forehead. He imagined himself in Italy, perspiring heavily, and drinking the white wine of Orvieto.

7. When the light of a candle screened with red paper was allowed to fall on his face, he dreamed of thunder, of heat, and of a storm at sea which he once witnessed in the English Channel.

Hervey, Weygandt, and others have made attempts to produce dreams experimentally.

Many have observed the striking skill of the dream in interweaving into its structure sudden impressions from the outer world, in such a manner as to represent a gradually approaching catastrophe (Hildebrandt). "In former years," this author relates, "I occasionally made use of an alarm-clock in order to wake punctually at a certain hour in the morning. It probably happened hundreds of times that the sound of this instrument fitted into an apparently very long and connected dream, as though the entire dream had been especially designed for it, as though it found in this sound its appropriate and logically indispensable climax, its inevitable denouement."

I shall presently have occasion to cite three of these alarm-clock dreams in a different connection.

Volkelt (p. 68) relates: "A composer once dreamed that he was teaching a class, and was just explaining something to his pupils. When he had finished he turned to one of the boys with the question: 'Did you understand me?' The boy cried out like one possessed 'Oh, ja!' Annoyed by this, he reprimanded his pupil for shouting. But now the entire class was screaming 'Orja,' then 'Eurjo,' and finally 'Feuerjo.' He was then aroused by the actual fire alarm in the street."

Garnier (Traite des facultes de l'ame, 1865), on the authority of Radestock, relates that Napoleon I, while sleeping in a carriage, was awakened from a dream by an explosion which took him back to the crossing of the Tagliamento and the bombardment of the Austrians, so that he started up, crying, "We have been undermined."

The following dream of Maury's has become celebrated: He was ill in bed; his mother was sitting beside him. He dreamed of the Reign of Terror during the Revolution. He witnessed some terrible scenes of murder, and finally he himself was summoned before the Tribunal. There he saw Robespierre, Marat, Fouquier-Tinville, and all the sorry heroes of those terrible days; he had to give an account of himself, and after all manner of incidents which did not fix themselves in his memory, he was sentenced to death. Accompanied by an enormous crowd, he was led to the place of execution. He mounted the scaffold; the executioner tied him to the plank, it tipped over, and the knife of the guillotine fell. He felt his head severed from his trunk, and awakened in terrible anxiety, only to find that the head-board of the bed had fallen, and had actually struck the cervical vertebrae just where the knife of the guillotine would have fallen.

This dream gave rise to an interesting discussion, initiated by Le Lorrain and Egger in the Revue Philosophique, as to whether, and how, it was possible for the dreamer to crowd together an amount of dream-content apparently so large in the short space of time elapsing between the perception of the waking stimulus and the moment of actual waking.

Examples of this nature show that objective stimuli occurring in sleep are among the most firmly-established of all the sources of dreams; they are, indeed, the only stimuli of which the layman knows anything whatever. If we ask an educated person who is not familiar with the literature of dreams how dreams originate, he is certain to reply by a reference to a case known to him in which a dream has been explained after waking by a recognized objective stimulus. Science, however, cannot stop here, but is incited to further investigation by the observation that the stimulus influencing the senses during sleep does not appear in the dream at all in its true form, but is replaced by some other representation, which is in some way related to it. But the relation existing between the stimulus and the resulting dream is, according to Maury, "une affinite quelconque mais qui n'est pas unique et exclusive" * (p. 72). If we read, for example, three of Hildebrandt's "alarm-clock dreams," we shall be compelled to ask why the same casual stimulus evoked so many different results, and why just these results and no others.

* A sort of relation which is, however, neither unique nor exclusive.

(p. 37): "I am taking a walk on a beautiful spring morning. I stroll through the green meadows to a neighbouring village, where I see numbers of the inhabitants going to church, wearing their best clothes and carrying their hymn-books under their arms. I remember that it is Sunday, and that the morning service will soon begin. I decide to attend it, but as I am rather overheated I think I will wait in the churchyard until I am cooler. While reading the various epitaphs, I hear the sexton climbing the church- tower, and I see above me the

small bell which is about to ring for the beginning of service. For a little while it hangs motionless; then it begins to swing, and suddenly its notes resound so clearly and penetratingly that my sleep comes to an end. But the notes of the bell come from the alarm-clock."

"A second combination. It is a bright winter day; the streets are deep in snow. I have promised to go on a sleigh-ride, but I have to wait some time before I am told that the sleigh is at the door. Now I am preparing to get into the sleigh. I put on my furs, the foot-warmer is put in, and at last I have taken my seat. But still my departure is delayed. At last the reins are twitched, the horses start, and the sleigh bells, now violently shaken, strike up their familiar music with a force that instantly tears the gossamer of my dream. Again it is only the shrill note of my alarm- clock."

"Yet a third example. I see the kitchen-maid walking along the passage to the dining-room, with a pile of several dozen plates. The porcelain column in her arms seems to me to be in danger of losing its equilibrium. 'Take care,' I exclaim, 'you will drop the whole pile!' The usual retort is naturally made- that she is used to such things, etc. Meanwhile I continue to follow her with my anxious gaze, and behold, at the threshold the fragile plates fall and crash and roll across the floor in hundreds of pieces. But I soon perceive that the endless din is not really a rattling but a true ringing, and with this ringing the dreamer now becomes aware that the alarm-clock has done its duty."

The question why the dreaming mind misjudges the nature of the objective sensory stimulus has been answered by Strumpell, and in an almost identical fashion by Wundt; their explanation is that the reaction of the mind to the stimulus attacking sleep is complicated and confused by the formation of illusions. A sensory impression is recognized by us and correctly interpreted- that is, it is classed with the memory-group to which it belongs according to all previous experience if the impression is strong, clear, and sufficiently prolonged, and if we have sufficient time to submit it to those mental processes. But if these conditions are not fulfilled we mistake the object which gives rise to the impression, and on the basis of this impression we construct an illusion. "If one takes a walk in an open field and perceives indistinctly a distant object, it may happen that one will at first take it for a horse." On closer inspection the image of a cow, resting, may obtrude itself, and the picture may finally resolve itself with certainty into a group of people sitting on the ground. The impressions which the mind receives during sleep from external stimuli are of a similarly indistinct nature; they give rise to illusions because the impression evokes a greater or lesser number of memory-images, through which it acquires its psychic value. As for the question, in which of the many possible spheres of memory the corresponding images are aroused, and which of the possible associative connections are brought into play, that- to quote Strumpell again- is indeterminable, and is left, as it were, to the caprices of the mind.

Here we may take our choice. We may admit that the laws of dream-formation cannot really be traced any further, and so refrain from asking whether or not the interpretation of the illusion evoked by the sensory impression depends upon still other conditions; or we may assume that the objective sensory stimulus encroaching upon sleep plays only a modest role as a dream- source, and that other factors determine the choice of the memory-image to be evoked. Indeed, on carefully examining Maury's experimentally produced dreams, which I have purposely cited in detail, one is inclined to object that his investigations trace the origin of only one element of the dreams, and that the rest of the dream-content seems too independent and too full of detail to be explained by a single requirement, namely, that it must correspond with the element experimentally introduced. Indeed, one even begins to doubt the illusion theory, and the power of objective impressions to shape the dream, when one realizes that such impressions are sometimes subjected to the most peculiar and far-fetched interpretations in our dreams. Thus M. Simon tells of a dream in which he saw persons of gigantic stature * seated at a table, and heard distinctly the horrible clattering produced by the impact of their jaws as they chewed their food. On waking he heard the clatter of a horse's hooves as it galloped past his window. If in this case the sound of the horse's hooves had revived ideas from the memory-sphere of Gulliver's Travels, the sojourn with the giants of Brobdingnag, and the virtuous horse-like creatures- as I should perhaps interpret the dream without any assistance on the author's part- ought not the choice of a memory-sphere so alien to the stimulus to be further elucidated by other motives?

* Gigantic persons in a dream justify the assumption that the dream is dealing with a scene from the dreamer's childhood. This interpretation of the dream as a reminiscence of Gulliver's Travels is, by the way, a good example of how an interpretation should not be made. The dream-interpreter should not permit his own intelligence to operate in disregard of the dreamer's impressions.