Classics in the History of Psychology

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Christopher D. Green
York University, Toronto, Ontario

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On the Witness Stand:
Essays on Psychology and Crime

Hugo Münsterberg (1908/1925)


THOSE stubborn people who simply did not believe that such a thing as hypnotism existed have probably now slowly died out; they might just as well have refused to believe that there are mental diseases. And those of the other extreme, those who saw in the hypnotic state a mystical revelation in which superhuman powers manifested themselves, have slowly lost their ground now; they might just as well call sleep or hysteria or epilepsy a supernatural mystery. No, science understands to-day that the facts of hypnotism are in no way more mysterious than all the other functions in the natural life of the mind. They are narrowly related to the experiences of absorbing attention, vivid imagination and obedient will and, on the other side, to sleep and dreams and mental aberration.

Of course, there nevertheless still remains much under heated discussion. There is no real agreement yet as to where the limits of hypnotism lie and where it shades off into suggestion. There are [p 204] various possible interpretations of the hypnotic brain process, various views also as to the special disposition for it, and even its symptoms still need careful inquiry. But everyone may agree at least in this: that hypnotism is not without serious con- sequences and is therefore certainly not a plaything. And secondly: that hypnotism is for many nervous and mental disorders a highly effective remedy when applied by the experienced physician. It has brought and will bring health and through it, happiness to uncounted sufferers, and therefore it has come to stay.

But if hypnotism is to be with us it seems natural that the question should be asked -- often not without anxiety: -- What is its relation to law and court, to crime and criminal procedure? The uncanny power which man has therein over men, will over will, suggests the thought that dangerous social entanglements may threaten or that new energies in the interest of the law may be made thereby available. The imagination has here a free field; the dime novel and, alas ! the dollar-and-a-half novel have made full use of this convenient instrument of criminal wonders, and the newspaper public [p. 205] reads, often without any feeling for the difference, stories of hypnotic crime which might easily have taken place by the side of others which are absolutely impossible. There is nowhere a standard, and it may therefore be worth while to take a bird's-eye-view of the whole field in which hypnotism and crime come really or supposedly in contact with each other.

The popular imagination turns first with preference to the query whether the court may not apply hypnotism for the purpose of unveiling the hidden truth. Unsolicited letters concerning hypnotism turn up copiously in a psychologist's mail; statistics show that it is just this proposition which disturbs the largest percentage of these amateur criminologists. They take a passionate interest in every murder case and too often reach the torturing stage of not knowing who is really guilty, even when all evidence and the verdict of the jury is in. Their scruple, they feel, could be removed only by their absolutely knowing that this or that man speaks the truth. Hypnotism has the well-known power of breaking down the resistance of the will; if the hypnotised witness [p. 206] were ordered to speak the full truth, he would no longer have any choice. It looks so simple and promising.

From a purely psychological standpoint such a method might be successful. It is not different in principle from the hypnotic confessions which a patient may make against his will. The other day a student whom I was curing of the cocaine habit assured me most vehemently that he had no cocaine in his room any more, and a few minutes later, when I had hypnotised him, he described correctly the place where he had hidden it. But the difficulty would begin with the fact, too often misunderstood, that one cannot be hypnotised by a new person for the first time against his will. A criminal who does not confess in his full senses will not yield to any hypnotising efforts, as no outsider can bring about the new state of mind. Hypnotisation cannot work on an unyielding brain as a sponge with chloroform which is held by force to the mouth might work. If the imagination of the subject does not help in reaching the somnambulic state, no one can inject a mesmeric fluid into his veins. And finally, even if such hypnotising by [p. 207] force were possible, it is self evident, from moral and legal reasons, that no civilised court ought to listen to such extorted evidence.

Of course, it might be different if a wrongly accused defendant or a suspected witness wished in his own interest to be hypnotised. A woman once asked my advice in such a case. She was under a cloud of ugly suspicion; even her own husband did not believe her protestations of innocence, and, I suppose, her lawyer still less. She wanted to be brought to the deepest state of hypnotism in open court till it would be evident that she had no will-power left for deceit. If she declared herself innocent on the question of the hypnotiser, the court would have to accept it. I advised her strongly not even to suggest such a theatrical performance. Technically, it is not at all possible to hypnotise everyone to such a strong degree, further it would be difficult to prove to the court that she did not simulate hypnotic sleep and that no secret agreement existed between the subject and her hypnotiser. But the decisive point for me was the conviction that the court ought to accept such somnambulic utterances as little as the [p. 208] insane speeches of a paranoiac. She would be no longer in full possession of her mental energies, as it is the essence of the hypnotic state that large parts of the inner functions are inhibited: all is suppressed which counteracts the suggestions of the hypnotiser. She thus would cease to be really herself, and the person on the witness stand would therefore not remain legally the witness who took the oath before the hypnotisation.

Quite different is the case when the hypnotisation is required to awake in the mind the memory of facts which occurred in an earlier hypnotic sitting. It is well known, indeed, that a person awaking from hypnosis may be without any memory of the words spoken, but may remember everything, even months after, as soon as a new hypnotic state is produced. Such a sharpened dream memory may become important, and here the break of personal unity is no hindrance, as the purpose is objective information; for such an end even an insane man may give acceptable evidence, perhaps as to the place where stolen booty is hidden.

But that the court should hypnotise would in any case be a most exceptional event; what is deserving [p. 209] of much more attention is the case when the criminal hypnotises. Here again popular misunderstandings prevail. Here belongs, first of all, the absurd fear of the man with paralysing powers. He enters the room and when he looks on you, you are powerless; you give him your jewels and the key to your safe and he plunders you gently while you have to smile and cannot raise a hand. The English newspapers insisted that such a "burglar with the hypnotic eye" is "the latest product of America." Punch, the London Charivari, poked fun at him with a long poem on John P. Beck of Fortieth Street -- Was as smart a burglar as one could meet. "On one thing only would he rely -- The power of his black hypnotic eye." At first John P. burglarises the halls of the millionaires. Finally he comes before the jury, but every witness begins to talk nonsense as soon as John P. looks at him. "And each who came through the witness door -- Seemed still more mad than the man before." And at last he looks on the judge, and the judge, too, begins to get confused and absurd and closes finally: "I know the criminal. Yes, you see -- The wretch before you. I am [p. 210] he! -- The man who should be in the dock is me! -- Arrest me, warders! Step down, John P."

Now all this is, of course, extremely funny, but Punch wanted to be still funnier, and therefore introduced, with a serious face, the burlesque poetry I with a prose remark. It closes with the statement: "Professor Miinsterberg of Harvard and other learned men have set themselves to show that hypnotic power may become a most dangerous asset of the criminal." That is amusing, indeed -- because hardly anyone who is interested in the psychology of hypnotic states has sought and used so constantly the chance to ridicule the belief in a special "hypnotic power." I know well that not a few disagree with me in this, but I must insist and have always insisted that anyone can hypnotise anyone.

Of course, whoever wants to hypnotise -- in fact, no one but a physician ought to do it -- must learn the technique and apply it patiently and skilfully. And certainly there are individual differences. Not everyone can be deeply hypnotised; with not a few the inhibition does not go further than the inability to open the eyes, while only one of [p. 211] four enters into strong hypnotic hallucinations. Further, not everyone is well prepared to awake that confidence which is essential and that feeling of repose which guides one over to the dreamy state; the look, the voice, the gestures, the phrases, the behaviour of certain persons make them poor hypnotisers, however well they may understand the tricks. But in principle everyone can hypnotise and can be hypnotised, just as in principle everyone can love and can be loved and no especial mysterious power is needed to fall in love or to awake love.

Yet, while thus everyone can exert hypnotic influence, no one can do it by a mere glance. All the stories of a secret influence by which one man's will gets hold of another man's mind are remainders of the mesmeric theories of the past. We know to-day that everything depends upon the attention and imagination of the hypnotised and that no mysterious fluid can flow over. This mystical view of unscientific superstition reached its climax in the prevalent belief that a man can exert such a secret influence from a far distance, without the victim's knowledge of the source of the [p. 212] uncanny distortion of his mind. Thus every heinous crime can be committed under that cover. The distant hypnotiser can inflict pain and suffering on his enemy and can misuse the innocent as instrument of his criminal schemes.

Such a reappearance of the old witchcraft superstitions is especially characteristic for the borderland cases between normal and abnormal minds. An unsound intellect easily interprets the stray impulses of the mind as the intrusion of a distant adversary. In Germany, for instance, a talented writer bombarded the legislatures with his pamphlets demanding new laws for the punishment of those who produced criminal perversions through telepathic influence. The asylums are full of such ideas. The paranoiacs are always inclined to explain their inner disturbances by the newest startling agencies. Their mind is disturbed by Roentgen rays or wireless telegraphy or hypnotic influence from a distance. In this country such accusations have become familiar to the students of Christian Science. In "Science and Health" Mrs. Eddy wrote, "In coming years the person or mind that hates his neighbour will have [p. 213] no need to traverse his fields, to destroy his docks and herds . . . for the evil mind will do this through mesmerism; and not in propria persona be seen committing the deed." And again, "Mesmerism is practised both with and without manipulation; but the evil deed without a sign is also done by the manipulator and mental mal-practitioner. The secret mental assassin stalks abroad and needs to be branded to be known in what he is doing." Or, "That malicious animal-power seeks to kill his fellow mortals, morally and physically, and then to charge the innocent with his crimes."

There ought to be no compromise: that morally ruinous doctrine of " Malicious Animal Magnetism'' is a complete distortion of the facts. Nothing of that kind is ever possible. Some agree that if the surprising facts of hypnotism are possible, such telepathic mesmerism might be possible too, as the influence looks similar. We might just as sell propose: if the surprising fact is true that a hen can be hatched from a hen's egg, it may also be true that a hen can come from a white candy egg, as they look alike. It is exactly the essentials [p. 214] of hypnotism and telepathy which are dissimilar and not to be compared: the latter would be a mystery, the former is no harder to explain than any act of sense impression and attention.

Of course, there is no reason to deny that a person may fall into hypnotic state while the hypnotiser is at another place. The only condition is, that he must have been hypnotised by him before and that his own imagination has been captured by the thought of the absent hypnotiser. I myself have repeatedly hypnotised by telephone or even by mail. I treated, for instance, a morphinist who at first came daily to my laboratory to be hypnotised; later it was sufficient to tell him over the telephone: Take your watch out, in two minutes you will fall asleep; or to write to him: As soon as you have read this note, you will be in the hypnotic state. I thus had the "malicious" influence over a distance, but it was not by will power, it was the power of his own imagination; at the time when he read my note in his suburb and fell asleep, I was not thinking of him at all. As a matter of course, such influences by correspondence would have been impossible had not [p. 215] repeated hypnotisation in personal contact preceded. Even that may not be necessary if not complete hypnotisation but only suggestive influence is in question. A few days ago I got a letter from a Southern lady whose son suffers from morphinism. I have never seen either of them. She writes: "My son has been impressed with the belief that your treatment is all he needs to be cured. In a dream, he said, you stood before him with the finger-tips of your hands trembling and said: I have the power to influence your will. He woke repeating: You have the power to control my will. That morning he seemed to forget to take the morphine at the regular time and soon went down to the beach without his morphine outfit in his pocket -- an unusual thing," and so forth. He himself was convinced that my will power was working on him while I did not even know him.

The chief factor is confidence. Anyone who saw the hypnotic effects, when the greatest master of hypnotism, Professor Bernheim of Nancy, in France, went from bed to bed in the clinics simply saying: Sleep, sleep, felt that indeed no one else could have attained that influence. But not [p. 216] because he had a special power: the chief point was that the whole population about Nancy went to him with an exaggerated tension of expectancy and confidence. I remember the case of a suffering woman whom I tried at first in vain to hypnotise; I felt that her mind was full of antagonism. I slowly found out what troubled her. She had seen so many physicians who had sent her high bills that she was afraid doctors humbug nervous patients for money. I told her that I, as a psychologist, do such work only in the interest of science, and that I, therefore, as a matter of course, have never accepted a cent from any patient anywhere. Two minutes later she was in deep hypnotic sleep. The attention and emotion of the subject is thus much more important than the power of the hypnotiser. Yet, this does not exclude the possibility that attention and emotion may be stirred up intentionally, perhaps even maliciously, without conscious knowledge of the victim. There is no especial power which produces love, and yet the coquettish smile of a wilful girl may perturb the peace of any man. In this way a hypnotiser may not wait till the subject lies down with the conscious [p. 217] expectation of being hypnotised, but may work slowly and systematically by means of a hundred little tricks on the imagination of a susceptible person. While both the hypnotic eye which fascinates the first glance and the malicious magnetism from a distance are absurd inventions, such slow and persistent gaining of power over an unresisting mind is certainly possible. A full hypnotic state cannot be reached in such a way; it shades off into the states of submission which belong to our normal social life; there is increased suggestibility in love and fear, in the pupil's feeling towards the teacher and the patient's feeling towards the physician -- nowhere a sharp demarcation line between these most valuable influences of social authority and the abnormal suggestions which have their climax in the complete hypnotic state. Such semi-hypnotic state can work, of course, also for good, but the dangers of its misuse are evident.

I remember the tragic case of a young Western woman who seems to have lived for years such a depersonalised social life. She had gone through college and graduate university work and every [p. 218] one of her instructors and comrades was charmed with the lovely girl; but her finest gifts showed themselves in her delightful family life. Her aged mother and her sisters were her only thoughts. The family made the acquaintance of an Italian who posed as a rich Italian count. He was without means, without education, disreputable and mannerless, from the lowest level. The girl was disgusted with him, but he managed to see her often. She felt with aversion how his influence grew on her; she felt a shiver when he looked at her, and yet an uncanny sensation crept over her, a strange fascination which she could not overcome; she had to do what he asked and finally what he ordered her to do. She despised him, and yet one day they secretly left the house and were married. At once he took possession of the young woman's considerable property. But it was not only that she gave him all; under his control she began absurd lawsuits to deprive the family of all they owned; she swore on the witness stand in court to the most cruel accusations and attacks against her mother, who had never wavered in her devoted love for her daughter, and everyone who knew her before [p. 219] felt from her expression and her voice that she was not herself any more, but that she was the passive instrument of an unscrupulous schemer. Her own mother said: "Sometimes, for a few minutes, I seemed to get near her -- then she would seem gone, miles and miles away. There are no words to describe the horror of it." And the sister wrote: "I should go crazy if I saw her often." And such a weird spectacle of an elusive mind, which is the old personality and yet not the old self, is not quite rare in our court rooms. It is a hypnotic state which is pregnant with social dangers, but certainly, as said before, there is no fear that it can be brought about suddenly or from a distance; it needs persistent influence, works probably only on neurotic persons with a special disposition for mental inhibitions, and never reaches complete hypnotism.

How far now does the full hypnotic state itself fall within the realm of criminal action? One aspect offers itself at once: the hypnotised person may become the powerless instrument of the criminal will of the hypnotiser. He may press the trigger of the gun, may mix the poison into the food, [p. 220] may steal and forge, and yet the real responsible actor is not the one who commits the crime but the other one who is protected and who directed the deed by hypnotic suggestion. All that has been demonstrated by experiments a hundred times. I perhaps tell the hypnotised man that he is to give poison to the visitor whom I shall call from the next room. I have a sugar powder prepared and assure my man that the powder is arsenic. I throw it into a glass of water before his eyes and then I call the friend from the next room. The hypnotised subject takes the glass and offers it to the newcomer; you see how he hesitates and perhaps trembles, but finally he overcomes his resistance and offers the sugar water which he must take for poison. The possibilities of such secret crimes seem to grow, moreover, in an almost unlimited way through the so-called posthypnotic suggestions. The opportunity to perform unwillingly a crime in the hypnotic sleep itself is in practical life, of course, small and exceptional. But the hypnotiser can give the order to carry out the act at a later time, a few hours or a few days after awaking.

[p. 221] Every experimenter knows that he can make the subject go through a foolish performance long after the hypnosis ended. Go this afternoon at four to your friend, stand before him on one leg and repeat the alphabet. Such a silly order will be carried out to the letter, and only the theoretical question is open, whether the act is done in spite of full consciousness, or whether the subject falls again under the influence of his own imagination at the suggested time into a half hypnotic state. Certainly he does not know before four o'clock that he is expected to do the act, and when the clock strikes four he feels an instinctive desire to run to the house of his friend and to behave as demanded. He will even do it with the feeling of freedom and will associate in his own mind illogical motives to explain to his own satisfaction his perverse desires. He wants to recite the alphabet to his friend because his friend once made a mistake in spelling, Might he not just as well run to his friend's house and shoot him down if a criminal hypnotiser afflicted him with such a murderous suggestion? He would again believe himself to act in freedom and would invent a motive. The situation [p. 222] becomes the more gruesome, as the criminal would have only half done his work in omitting to add the further suggestion that no one else would ever be able to hypnotise him again and that he would entirely forget that he was ever hypnotised. Experiment proves that all this is entirely possible, and that posthypnotic suggestion thus plays in literature a convenient rôle of secret agency for atrocious murder as well as for Trilby's wonderful singing.

In contradiction to all this I have to confess: I have my doubts as to the purity of Trilby's hypnotic singing, and I have more than doubts -- yes, I feel practically sure that no real murder has ever been committed by an innocent man under the influence of posthypnotic suggestion. It is true, I have seen men killing with paper daggers and poisoning with white flour and shooting with empty revolvers in the libraries of nerve specialists or in laboratory rooms with doctors sitting by and watching the performance. But I have never become convinced that there did not remain a background idea of artificiality in the mind of the hypnotised, and that this idea overcame the resistance [p. 223] which would be prohibitive in actual life. To bring an absolute proof of this conviction is hardly possible, as we cannot really kill for experiment's sake.

There remains, of course, also the possible claim that the courts have condemned men for murder for which they were passive instruments. Yet, it is a fact that so far no murder case is known in which the not unusual theory of the hypnotic influence seemed probable after all evidence was in. I have repeatedly received inquiries from lawyers asking whether there would be any basis to stand on if the defence were to claim that the crime was done in a hypnotic or posthypnotic state. I have replied every time that, in spite of the many experiments which seem to prove the contrary, it can be said that hypnotic suggestion is unable to break down the inner resistance. There is therefore no danger to be feared from this side. The frequent claim of defendants that they must have been hypnotised is, nevertheless, mostly no conscious invention. It is rather the outcome of the fact that the criminal impulse comes to the unbalanced diseased mind often like [p. 224] a foreign intruder; it takes hold of the personality without free choice of motives, and the unfortunate sufferer thus interprets quite sincerely his unaccountable perversions as the result of strange outside influences.

But there is another side, and it would be reckless to overlook the difference. You cannot make an honest man steal and kill, but you can make him perform many other actions which are not immoral as far as the action is concerned and which yet have criminal character. The scoundrel perhaps gives the posthypnotic suggestion that his subject, a man of independent means and without immediate relatives, call at a lawyer's and deposit with him a last will leaving all his property to the hypnotiser. Here no resistance from moral principle is involved; the man who throws away all he owns acts in accordance with the order because the impulse is not checked by the habits of a trained conscience. We can add one more step which is entirely possible: the hypnotiser may see a further opportunity to give the posthypnotic suggestion of suicide. The next day the victim is found dead in his room; everything indicates that [p. 225] he took his own life; there is not the least suspicion: and the hypnotiser is his heir in consequence of the spurious last will. Similar cases are reported, and they are not improbable. The easiness with which any hypnotiser can cover the traces of his crime by special suggestions makes the situation the more dangerous.

In this group belong also the posthypnotic perjuries. Of course, if the man on the witness stand knew that he swore falsely, his moral convictions would rebel as in the case of the theft and murder. But he believes what he swears; on his side there is no crime, but merely confusion of ideas and falsified memory; the crime belongs entirely to the one who fabricated the artificial delusion.

In many of these cases the hypnotised subject is the sufferer while he himself is acting; they are not seldom supplemented by crimes in which the subject is a passive sufferer. The French literature of hypnotism is full of cases in which hypnotised women have been the victims of sexual crime. No warning can be loud enough, indeed, against hypnotising by anyone but reliable doctors of medicine. Other cases refer to simple [p. 226] fraud. The posthypnotic suggestion may force one man to pay the price of real pearls for glass pearls and may induce another man to buy a house which is useless for him. The physician who is a trained psychologist will have no difficulty in assisting the court in all such situations and in making the right diagnosis; on the other hand, without thorough experience in scientific psychology, no one will be able to disentangle such cases, be he physician or not. The hypnotiser may have suggested complete forgetfulness and may have prohibited any new hypnotisation, but there always remains somewhere a little opening where the psychologist can insert a wedge and finally break open the whole mental structure. It may be added at once that the psychologist has also no difficulty in recognising any simulation of hypnotic states.

There remains still one important relation between hypnotisation and crime: hypnotisation may prevent crime. The moral interest we take in the suppression of criminal impulses makes us inclined to see a sharp demarcation line between these socially destructive tendencies and other impulses which are morally indifferent. Psychologically we [p. 227] cannot acknowledge such a distinct line between them. The craving for an immoral and illegal end may take possession of a weak nervous system in the same way in which any neurasthenic impulse becomes rooted, and it seems therefore not unjustified to hope for such a criminal disposition the same relief by hypnotic treatment as for the neurasthenic disturbance.

Last year I was approached within the same week by two young people who complained in almost identical terms that they could not master their ideas and desires. The one suffered from the idea that he wanted to kill certain persons; whenever he saw them he felt the impulse to knock them down. The other suffered from the idea that she wanted to look alternatingly from one eye to the other of any person with whom she talked. The impulse to kill was possibly of the greatest consequence, the impulse to look from eye to eye was evidently the most indifferent affair. And yet the second person was the greater sufferer. She had once by chance observed in a man's face a striking difference in colour between his two eyes, and that led her to look alternatingly to the one and [p. 228] the other eye. It became a habit which grew stronger than her will and, when she came to me, it had reached a point where she thought of suicide because life had become intolerable from this incessant impulse to swing from eye to eye. I treated the dangerous killing impulse and the harmless swinging impulse exactly alike, by inhibitory suggestions, and they disappeared under the hypnotic treatment in exactly the same time.

But it is evident that the criminal impulses can- not be simply treated as an appendix to the neurasthenic states. Most complex and partly moral questions are involved therein. Have we a right to reinforce righteousness by hypnotic instead of by an appeal to spiritual energies? If we cure the depraved boy of his stealing habit by hypnotism, would it not be the simple logical consequence that his whole education and training ought to be left to such a safe and forceful influence? And that opens the widest perspective of social problems. It leads us to a new and separate question: What can the modern psychologist contribute to the prevention and suppression of crime ?