Since the past history of hypnotism verged upon the marvellous, it had the privilege of exciting the curiosity, not only of learned men, but of people in general. Exhibitions with which science had nothing to do made the public acquainted with a certain number of phenomena of which a criminal use might be made; and hypnotic sleep and suggestion have played a part in several judicial dramas.* One of the present writers was therefore justified in being the first to call attention to the study of hypnotism from the medico-legal point of view, in a paper which only treated of profound hypnotism, characterised by symptoms of a physical kind.+ Liegeois
has subsequently communicated to the Academy of the Moral and Political Sciences a paper on the same subject, regarded from a somewhat different point of view, and this has given rise to lively discussions.* We think it may be profitable to consider this subject, which is indeed entitled to further development.
Most of the writers on this question have been chiefly occupied in throwing light on the possibility of accomplishing criminal acts by means of hypnotism, but they have not considered the question of proof. They have not asked under what conditions judges would admit the reality of the facts of hypnotism brought before them. They have not understood that in a medico-legal study, the demonstration of the hypnotic state is the first question, and the most important of all; the others are comparatively unimportant, since if the hypnotism is not proved, all the consequences which may be drawn from it become illusory. It need hardly be added that a scientific demonstration of hypnotism can only be made by means of objective and material signs. Several observers have accepted as proofs the honesty and good faith of their subjects, but these words do not involve any objective sign. Moral proofs must always remain personal to those who appeal to them, and cannot be taken into account in a medico-legal study. We cannot hope to convince judges of the reality of a state in which all the phenomena may be simulated. To accept the fact hypnotism on the ground of moral proofs would be to open the door to innumerable abuses of the most serious character.
The medico-legal question may be briefly stated in the following terms. An individual appeals to the law, asserting that he has been the victim of some violence, or of a suggestion, after he had been thrown into the hypnotic state. It may be admitted that the assertion is probable, if it is proved experimentally that he is susceptible to hypnotism, and that he displays a certain number of objective, characteristical phenomena, but this proof can only be obtained if he voluntarily submits to be subjected to experiment. Again, an individual accused of a crime or an offence, may plead that he acted under the influence of an impulse suggested during the hypnotic sleep, and in this case also it is necessary to obtain a material proof that the subject is susceptible to hypnotism. As a general rule, whenever an accused person pleads hypnotism, the fact should be proved by subjecting him to experimental observation.
Another situation may occur. A witness may be suspected of making a deposition dictated by hypnotic suggestion. If the fact of suggestion is established by material proof, the fact that he has borne false witness will also be demonstrated. If the material fact cannot be established, the difficulty is almost insuperable, since an individual cannot be constrained to submit to hypnotization, any more than to take chloroform or haschish.
The conditions which enable an expert to affirm that a person is susceptible to hypnotism are as follows. The hypnotized subject must display its physical phenomena, and must be a subject of profound hypnotism. Profound hypnotism may occur either in a perfect or imperfect form; that is, some of the established phenomena may be absent in a given subject without affecting
its general aspect, if a sufficient number of characteristic phenomena remain.
In slight hypnotism, in the states described as fascination, magnetic sleep, etc., subjects appear to be peculiarly liable to suggestion. It is possible to develop in them catalepsoid states, muscular rigidity, fixed attitudes, paralysis, anaesthesia, various hallucinations and impulses; but not the special and characteristic states described above under the names of catalepsy, lethargy, and artificial somnambulism. These subjects only display a few physical phenomena which have not yet been the object of a regular nosographic study. The strict attention with which the facts should be examined, must be redoubled in such cases, since the only criterion is afforded by physical phenomena. Until we know more of the subject, a person who displays none of the physical characteristics of hypnotism cannot plead it as a justification. It is practically impossible to define in any other way the limits of normal suggestibility.
After having shown how the expert may satisfy himself that a subject is susceptible to hypnotism, we must consider the special circumstances in which it is possible to admit the probability of hypnotization.
The hypnotic sleep, which is produced with so much difficulty and delay in fresh subjects, occurs with alarming rapidity in those who have been long under treatment. Some of our patients are hypnotized at once by a single abrupt gesture, and this may be effected in all places alike, and at any hour of the day. If we meet one of these subjects crossing the courtyard, an exclamation or abrupt gesture will cause her to stop
short and become motionless in catalepsy. She may he as instantaneously awakened by breathing on her forehead or eyes. The hypnotic sleep may, therefore, be produced and brought to an end in an extremely short time, we might even say during the passage from one door to another. This is a somewhat important fact from the medico-legal point of view. And again, a suggestion may be given in a sleep of very short duration. We have observed that in the course of fifteen seconds we could throw a subject into a lethargy, then into somnambulism, suggest an act, and then awake him. It is, therefore, possible that an individual might make use of the fifteen seconds in which he found himself alone with a susceptible subject to inculcate an idea, an hallucination, or an impulse. We must not rely on a question of time in maintaining the impossibility of such a fact, since the time required to hypnotize and suggest to an habitual subject of experiment is so extremely short.
Experience also shows that we must not accept the subject's assertions in estimating the duration of hypnotic sleep. The subject is unable to measure the length of time she has slept, and if she attempts to do so she makes the gravest mistakes. For instance, one of our subjects whom we had hypnotized for a period which did not exceed twenty seconds, believed that she had slept an hour, and in other cases there was equal miscalculation. The hypnotic subject has no landmarks by which to measure the void which this sleep produces in the normal course of life. We must not, therefore, deny the reality of an hypnotic suggestion, merely because the experimenter had only a minute's
contact with the subject, although she asserts that she has slept for hours.
We unfortunately possess but few documents bearing on the question how far the subject is aware that he has been hypnotized. Some of those on whom we have been performing experiments for a whole morning, do not know how often they have been hypnotized and awakened; but they have a general knowledge, of having been subjected to hypnotism. They know this from an impression of cold, a shivering which often lasts long after they are awake. But this sign is not of much value, since it may not only be absent, but destroyed by suggestion, and it is less marked in proportion to the shortness of the sleep.
In cases of profound hypnotism there is often an oblivion of what occurred during the hypnotic sleep. This oblivion is complete when the experimenter has taken care to tell the hypnotized subject that he will remember absolutely nothing. The oblivion is also rendered more profound when the subject has not been directly recalled to the waking state, but has passed from somnambulism into lethargy, from lethargy again into somnambulism, and thence into the waking state. On the other hand, the amnesia is often only partial when the subject is awakened immediately after the occurrence of a given fact; a more or less vivid recollection of it still remains. The hypnotic subject seems to be in the same situation as a man who awakes from normal sleep; he has a vague recollection of what he has seen, or of what has been said to him during sleep, and he thinks that he has been dreaming. Finally, the events which occurred during hypnosis recur to his mind with
great force, when they are recalled by some external object or circumstance.
Thus it appears that it is impossible to lay down an absolute rule as to oblivion on awaking; there is, in fact, every variety of case, from the most profound oblivion to the most lucid recollection, and these are all entitled to careful consideration from the medico-legal point of view.
A suggested amnesia is the most important of these situations. It must always be borne in mind that a suggestion will destroy the subject's recollection of all which has occurred to her during hypnosis. This want of memory, which may either occur spontaneously or be artificially produced, is possible even when the subject has experienced a shock, of which the effects are painful or more or less enduring. In the course of an experiment, one of our subjects, who was in a state of lethargy, fell down and knocked her head violently against the floor. She was not awakened by this excitement, nor for some time afterwards, and she was then awakened by breathing on her face. On coming to herself, the subject was astonished by the pain in her head; she had the sensation of a violent blow or shock, and could not understand whence it came. We are, therefore, justified in the assertion that a subject of profound hypnotism may undergo all sorts of violence without retaining any recollection or consciousness of it, unless the violence has produced permanent lesions, such as the attrition of the tissues resulting from a violent shock, etc. We even think it possible that a subject might be violated in the hypnotic state, in which she would be unable to offer any resistance.
We turn from the subject who has forgotten everything, to the subject who asserts that she remembers everything, in order to consider whether her story is to be believed. It is a serious question, and admits of many hypotheses.
In the first place, the subject may be perfectly honest, and yet the victim of an illusion. When a subject finds on awaking that she is suffering from a wound, or from some serious or unpleasant affection, she is apt to look for an explanation, and sometimes she invents an explanation for herself. Sometimes, again, she accepts it from a third person, but in all cases she ends by suggesting to herself that she saw things occur as she has explained them; in other words, the explanation has led to an hallucination of memory. Thus a subject who has, during hypnosis, received a blow from a third person, may explain her injury by the supposition that she fell down, and she will maintain the reality of this imaginary fall with the strongest conviction. The medical jurist must be on his guard against the remarks and explanations adopted by the subject to account for the accidents which happen to her, and her assertions should not be accepted without confirmation.
The subject may err from another cause, the suggestion of the experimenter, who has impressed upon her a recollection which is false. It is impossible for the expert to steer clearly amid all these phenomena, and to make a categorical declaration as to the way the thing occurred.
Finally, the subject who in the waking state remembers what occurred during hypnosis, may simulate. This danger of simulation is always present in a legal
case, whatever be the physical state of the subject. Even in a case of profound hypnotism, we must not blindly accept whatever is related by the subject. The testimony may be recorded, and taken for what it is worth, in conjunction with other facts, but this is not the business of the expert.
We have hitherto regarded the subject in a state of repose, and we must now consider him in a state of activity, influenced by suggestions or excitements. We will begin with the study of hallucinations. The subject may, for instance, be induced to mistake the identity of a person, or to accept the presence of one who is really absent, and to recognize his features, voice, etc. The possible consequences of this illusion or hallucination are evident. If an unlawful or criminal act should be committed on the subject, or in her presence, an accusation might be made against an innocent person, and it would be maintained with the deepest conviction. The illusion or hallucination might apply to the act itself, and would lead to analogous consequences.
Some writers have lately returned to this question, of which we long ago noted the importance. They devised some dramatic experiments, to illustrate the criminal use which might be made of hypnotic hallucination, but we do not think it necessary to reproduce them. It seems to us more important to inquire under what conditions these facts of retrospective hallucination can be adduced in a court of justice. As we have already said the medico-legal question of hypnotism is reduced to a question of diagnosis, and it may be added that whatever is not diagnostic in the legal questions which affect hypnotic subjects is not within the province of the
physician. The expert has not to decide upon the reality of a fact of suggestion, but on its possibility; and in order to do this, he must establish by experiment the fact that the phenomena under dispute can be reproduced in a given subject, by means of an hypnotic suggestion. We are, therefore, concerned to know what are the objective signs which demonstrate the hallucinations produced in a given subject to be genuine. We propose to dwell chiefly on hallucinations of vision, since they are the most easy to examine, and we can deduce from them the sincerity of the hallucinations of the other senses.
Hallucinations of vision, whether induced by verbal suggestion, or by any other process, are chiefly characterized by their power of duplication, either when a prism is placed before the eyes, or when a mechanical deviation is effected. The hallucinatory object may be enlarged or diminished in size by a lens, and may be reflected and rendered symmetrical by a mirror. If a coloured object is in question, it may give rise to a subjective sensation of the complementary colour, and if the hallucination is unilateral, it may be transferred to the other side by the action of the magnet. Finally, if the imaginary object is brought nearer, or withdrawn, there is a corresponding dilation and contraction of the pupil. These movements to accommodate the sight occur spontaneously in very few cases, and only under known conditions.
It should be added that in the case of some subjects, the general sensibility of the eye is profoundly modified during the period of visual hallucination; there is, in fact, speaking generally, insensibility of the conjunctiva and of the cornea, as well as of the region of the pupil.
These may, in the case of most subjects, be touched with a foreign body, without producing any reflex action of the eyelid. In P—, however, when a visual hallucination has been developed, the sensibility of the external membranes of the eye is normal.
All these signs enable the expert to know whether a subject can or cannot receive an hallucination by suggestion, but they by no means establish the fact that the hallucination has actually occurred. This is a distinct question, which it is the part of the legal examination to elucidate.
Systematic anaesthesia serves as a counterpart to hallucination, and must be considered in conjunction with it. It may be suggested to a subject before whom a crime or offence is to, be committed, that he is unable to see a given person. The possibility of making such a suggestion would enable a criminal to get rid of a troublesome witness, and the subject might then declare in a court of justice, in all good faith, that he had seen, heard, and felt nothing.
We need only remind our readers of the numerous proofs of systematic anaesthesia. The first of these is the Chinese gong. A subject susceptible to hypnotism who instantly becomes cataleptic at the sound of the gong, is no longer affected by catalepsy when it is sounded after his perception of the instrument has been destroyed by suggestion. A second proof is derived from the complementary colours. When it has been suggested to the subject that he cannot see the colour red, his fixed gaze at an invisible square of red produces after a while a consecutive green image. Finally, the action of the magnet impresses a special character on
systematic anaesthesia. The expert may ascertain from these signs whether a given subject, placed in a state of hypnotism, is capable of affording authentic instances of anaesthesia.
It is possible to suggest to a subject in a state of somnambulism fixed ideas, irresistible impulses, which he will obey on awaking with mathematical precision. The subject may be induced to write down promises, recognitions of debt, admissions and confessions, by which he may be grievously wronged. If arms are given to him, he may also be induced to commit any crime which is prompted by the experimenter. We could cite several acts, to say the least unseemly, committed by hysterical patients, which were crimes in miniature, performed by an unconscious subject, and instigated by one who was really guilty, and who remained unknown. At the Salpêtrière a paper-knife has often been placed in the hands of an hypnotic subject, who is told that it is a dagger, with which she is ordered to murder one of the persons present. On awaking, the patient hovers round her victim, and suddenly strikes him with such violence that I think it well to refrain from such experiments. It has also been suggested to the subject to steal various objects, such as photographs, etc.
These facts show that the hypnotic subject may become the instrument of a terrible crime, the more terrible since, immediately after the act is accomplished, all may be forgotten — the crime, the impulse, and its instigator.
Some of the more dangerous characteristics of these suggested acts should be noted. These impulses may give rise to crimes or offences of which the nature is
infinitely varied, but which retain the almost constant character of a conscious, irresistible impulse; that is, although the subject is quite himself, and conscious of his identity, he cannot resist the force which impels him to perform an act which he would under other circumstances condemn. Hurried on by this irresistible force, the subject feels none of the doubts and hesitations of a criminal who acts spontaneously; he behaves with a tranquility and security which would in such a case ensure the success of his crime. Some of our subjects are aware of the power of suggestion, and when absolutely resolved to commit an act for which they fear that their courage or audacity may fail when the moment arrives, they take the precaution of receiving the suggestion from their companions.
The danger of these criminal suggestions is increased by the fact that at the will of the experimenter, the act may be accomplished several hours, and even several days, after the date of suggestion. Facts of this kind, which were first reported by Richet, are not exceptional, and have been repeatedly observed by us.
The reality of this class of facts cannot now be disputed, but the difficulty of proof in any given case is considerable. We have not, in the case of impulsive acts, the same objective criterion as we have in hallucinations and in the paralysis of movements and of sensation. It is, therefore, necessary for the expert to be cautious in his judgment.
Loss of memory is one chief characteristic of the facts of suggestion. The hypnotic subject does not know from whom, when, and how the suggestion was received. This amnesia may be either spontaneous or suggested,
and it is a phenomenon of the waking state, which disappears when the subject is hypnotized anew. The recollection o£ all which occurred during hypnosis is then revived, and the subject is able to indicate, often with remarkable precision, the author of the suggestion, the place, day, and hour when it was made to him, always supposing that he has received no special suggestion of complete oblivion. Hence the question occurs whether an accused person who appeals to an hypnotic suggestion for his defence, and who submits to experiment, can be profitably examined at a time when he displays all the physical characteristics peculiar to the somnambulist state, so that there is no danger of imposture. We have had occasion to show that some subjects are in this state capable of suppressing the truth, and Pitres has shown that deceit was not impossible. An hypnotic subject may at the same time be criminal, and suggestion must be accepted only so far as it admits of material proof, or at any rate as far as it can be necessarily deduced from the facts of the case.
Simulation is not the only danger to be avoided in the examination of a somnambulist subject. It is possible that a magistrate or physician may, by the persistence of his questions and his authoritative voice, unconsciously give suggestions which modify the subject's recollections, and give rise to hallucinations of memory. There is a further danger that the examination of the subject may conflict with a previous suggestion, by which he had been forbidden to speak of certain events. It is true that a little dexterity will overcome this defence, as, for instance, by assuming, by means of suggestion, the personality of the first experimenter. But the facts we
have given are enough to show that the examination of an hypnotic subject does not afford a sufficient warrant of her sincerity.
There is still more reason for condemning an inquiry by means of hypnotism. It has been suggested that a suspected or accused person might be hypnotized against his will, in order to obtain from him admissions or information respecting the facts of the accusation. This process, which resembles that of torture, would have the same danger of leading a suspected person to confess crimes of which he was not really guilty.
We should say, in conclusion, that the suggestion of crime, whether made in or out of the hypnotic state, upon hypnotic or neuropathic subjects, can only be proved by the physical characteristics furnished by the subject. The medical expert, whose duty it is to bring justice to light, and not to find victims for the law, must be content with this observation. He may prove by experiment that a given subject is or is not susceptible to hypnotism, and that the phenomena in question may be produced during hypnosis, or under the influence of an hypnotic suggestion, but he can only give evidence of the possibility of the fact. It is for others to decide whether the fact really occurred.
When once the suggestion has been proved, it remains to be seen what is the penal and moral responsibility of the individual who has acted under the influence of an hypnotic suggestion. We think that some authors have been too hasty in deciding that the moral responsibility of the subject has absolutely ceased. We should at any rate inquire why he consented to be hypnotized, unless this was done suddenly, or by force or guile. Even if
he was not aware of the experimenter's purpose in hypnotizing him, he must be held responsible for having voluntarily alienated his free will This principle may certainly be established, and it is still more applicable if the subject was aware before he was hypnotized for what criminal act it was proposed to employ him. This hypothesis is by no means impossible.
It is possible that a subject susceptible to hypnotism might be found in a band of swindlers or murderers who would willingly become the recipient of criminal suggestions. We can readily understand the use of suggestion in such circumstances, since those who act under the influence of hypnotic suggestion display more daring and courage, and even more intelligence, than when they act from their own impulse.
Even when the subject has been hypnotized without his consent, when he has been taken by surprise, and has received the suggestion during his waking state, and has consequently incurred no moral responsibility, it cannot be denied that society is justified in defending itself against such a dangerous subject. So far, hypnotism has only made a casual appearance in a court of justice. But this state of things might change at any time, and suggestion may become an instrument of criminal practices. No one who studies the history of crime will maintain that society ought not to guard against such a danger. Hypnotic criminals ought to be treated like insane criminals.*
Since the possibility of curing a certain number of nervous diseases by means of hypnotism is established,
it cannot be disputed that physicians are justified in making use of it, under the same reservation as any other methods of therapeutics. The physician's responsibility is diminished if he has to treat an affection which would not yield to other measures; if he has obtained the consent of his patient and the concurrence of the patient's friends, and, finally; if he can show that he has acted prudently, with due consideration of the danger incurred by the patient, and with proper precautions against these risks.
Some reservations must be made with respect to experiment, strictly so called.
Some facts recently observed in Italy seem to indicate that the practice of hypnotism may produce in the subject permanent nervous affections. Yet to assert that experiments must, therefore, be prohibited would imply that there are truths which it is better not to knew. It is, however, certain that the prejudice should be overcome by those who have excited it, and that men are not freed from all responsibility by the fact that they possess a diploma. If, instead of considering the interest of the patient, the result of the experiment is the only object in view, it may come to pass that, on pretence of shedding light on the highest problems of physiology or psychology, inquirers who are not thoroughly acquainted with anatomy, physiology, and therapeutics, may imperil the lives of subjects committed to their care. Ignorance of the danger is no valid excuse for the imprudence of the experimenter.
It is only on these conditions that experiments on the human subject should be performed, and it may be said in passing that there is nothing in them which need
appear shocking. It is indeed an every-day practice, since in laboratories and hospitals, patients or students are always willing to submit to the action of drugs or to physiological experiments, and experiments in hypnotism may be performed without inconvenience under the same conditions and safeguards.
With respect to the performance of such experiments in public, it should be condemned, just as we condemn public dissections of the dead body, and vivisection in public. It is certain that there are still graver objections to hypnotic exhibitions, since they are liable to produce nervous affections, even in those who do not propose to be the subjects of experiment.
THE END.