The Very First Multiple Personality
MULTIPLE means more than two. Neither double consciousness nor dédoublement was multiple personality. Advocates of the diagnosis of multiple personality will want to say that Félida had more than two alters; we have intimations of as many as five. Under a different type of treatment all might have flourished; they might have been clues to Félida’s underlying distress. But if we ask about what was, rather than what might have been, Félida had exactly two alternating personalities. That was how she was thought of, described, talked about, treated by her family, and regarded by her neighbors. That was how she felt about herself; that was how she experienced herself. In terms of symptom language, there were no actually multiple personalities when Félida became famous. Whatever might have been, had patients been treated differently, there were in fact only doubles. When did multiple personality come into being? Late in the afternoon of the 27th of July, 1885.
On that afternoon Jules Voisin, a student of Charcot’s and a leading physician at Bicêtre, the Paris asylum for men, described a patient who had been under his care from August 1883 until 2 January 1885. His name was Louis Vivet. He was presented as a case of grande hystérie chez l’homme avec dédoublement de la personnalité. Voisin noticed some differences from Félida, but he still found it convenient to “use the terminology of Dr. Azam,” namely, first and second states. Louis Vivet had dédoublement. By 1885 that was not especially interesting. Voisin was nevertheless fascinated by the man as a perfect, prototypical hysteric. He had all the extreme symptoms of hysteria that, in Charcot’s ward, were commonplace among females. “In the long bibliography of male hysteria, one mostly encounters cases of hysteria that only roughly fit the prototype.”1 Vivet was marvelous because he had the whole gamut of symptoms familiar to doctors trained under Charcot at the Salpêtrière.
By what may have been a coincidence, one Dr. Hippolyte Bourru (1840–1914) was in the audience. Vivet had escaped from Bicêtre on 2 January 1885 but soon afterward came under the care of Bourru and his colleague, P. Burot. Bourru had a new story to tell. Louis Vivet had not been long at large. At the end of February 1885 he was consigned to the military hospital in Rochefort and was there attended by Bourru and Burot. By July 1885 Bourru could report an entirely new phenomenon in the annals of psychiatry. Vivet had eight distinct personality states.2 The meeting broke up at 6:30 P.M. The discourse of multiple personality had just been put in place. Our phrase “multiple personality” appeared in print in England within a year, explicitly to describe Louis Vivet.3
To understand what happened we have to enter one of the zanier reaches of our topic. First there was metallotherapy: it seemed that hysterical anesthesias, contractures (muscular spasms producing an enduring shortening of a limb), and paralyses could be removed if the appropriate part of the body were touched with magnets or various metals. In 1877 the Societé de Biologie established a commission to report on the method. The commissioners included Charcot and J. B. Luys (1828–1892). They observed more than they seem to have expected. Many bodily symptoms of hysteria such as paralysis, anesthesia, or contracture occurred on one side of the body. A left arm or leg might be affected; there was also left hemiplegia (paralysis of most or all of the left side of the body). Charcot, Luys, and their fellow commissioners found that symptoms could be transferred from one side of the body to another if they touched the first side with a magnet, or another piece of metal, and then applied the metal to the other side of the body. The symptoms obligingly moved with the metal. The most systematic experiments were made by Alfred Binet (1857–1911) and his colleague Charles Féré.4 Charcot’s great critic from Nancy, Hippolyte Bernheim (1840–1919), argued that if there was anything to these phenomena, they were solely the consequence of what he called suggestion. Binet’s startling reply was that to deny the action of the magnet on an organism was to deny the action of electricity.5 Soon afterward Binet was to write an enthusiastic tract about objective experiments confirming double conscience, stating firmly that the topic had now passed from the realm of pioneering exploration to science.
The young neurologist Joseph Babinski (1857–1932), a student of Charcot’s, made a further discovery. We remember him for the Babinski reflex, but Babinski also discovered that you could use a magnet to transfer symptoms not just from one part of the body to another, but also from one person to another. You separated two somnambules (artificial or spontaneous) by a screen. Mrs. A’s right arm, say, was paralyzed. You applied a magnet to Miss C’s right arm. Mrs. A’s right arm became mobile again, while Miss C’s became paralyzed.6
Luys built on these results to develop an amazing method of therapy. He would transfer the real symptoms of a hysteric patient to a hypnotized patient by drawing a magnet along a limb of the ill person and on to the corresponding limb of the healthy but hypnotized one. The latter would assume not only the symptoms but also the personality of the hysteric. Then the somnambule would be awakened, the symptoms would vanish from everyone, and the hysteric would assume her own personality, without the paralysis or whatever else afflicted her.7
Bourru and Burot took this one step further. They put various liquids in tiny flasks and wrapped solids in paper. Often these were drugs, including alcohol. They would hold a drug or other substance behind a patient’s head. After a short time, the patient would fall ill or get better as if he had actually swallowed the stuff. Louis Vivet was one of the two prime exhibits (another was a woman in Charcot’s ward). Luys then put all these techniques together, achieving even more remarkable phenomena. Finally the Académie de Médecine got into the act and was unable to reproduce any of these phenomena at all. So much for background: it matters because Vivet’s many states were induced by the application of magnets, metals, and metallic compounds such as gold bromide, and because he was used as a prime exhibit of the action at a distance of numerous metals and medications.
Cynics have decried multiple personality as folie à deux, a madness resulting from a strange if unwitting collaboration between patient and therapist. I have not made that accusation, nor will I in the future. But I have no doubt that the case of Louis Vivet involves what we might call folie à combien? I do not know how many people participated for long periods of time, but there were at least five, namely, Vivet, Bourru and Burot, a colleague of theirs, Mabille, and Jules Voisin. I have the names of some twenty physicians who worked with or witnessed Vivet’s curious conditions. Charcot certainly saw him. Vivet was personally observed by at least as many topflight clinicians as have ever examined anyone.
In his faithful and admiring History of Hypnotism Alan Gauld can scarcely restrain his impatience with characters such as Luys who brought hypnotism into disrepute. We find expressions such as “positively crazy” and “still crazier” when Gauld turns to the “associated extravagances” of metallotherapy, including those of Bourru and Burot.8 Why not leave it at that? Partly because there is a difference of opinion. Adam Crabtree writes that the book about Louis Vivet which Bourru and Burot issued in 1888 “ranks as the most important study of a single case of multiple personality to be published in the nineteenth century and contains significant advances in understanding the genesis and therapy of that condition.”9 As science and medicine the work of Bourru and Burot is, in my opinion, rubbish. It is nevertheless important not only because it presents the very first multiple, but because, in Crabtree’s words, “the connection between specific personalities and specific memories was acknowledged.”
This work inaugurated a new language of genuinely multiple personality. I am not here calling in question the truth of the descriptions furnished by Bourru and Burot. And of course the fact that his doctors were engaged in “positively crazy” research does not mean that Louis Vivet was a deliberate fraud. He was a very sick man. As usual, I am not concerned with what Vivet “really had.” I am concerned with what was said about him, how he was treated, and how the discourse and the symptom language of multiple personality came into being.
I shall sketch some salient points in the life of Louis Vivet but I will not dwell on his bodily ailments. Aside from conditions that explicitly require female reproductive organs, Vivet displayed virtually every type of bodily distress known to the language of hysteria in the late nineteenth century. That was why Voisin presented the case to the Société Médico-psychologique. Every kind of pain, paralysis, anesthesia, contracture, muscular spasm, hyperesthesia, mutism, rash, bleeding, coughing, vomiting, convulsing; every kind of epileptic seizure, catatonia, somnambulism, Saint Vitus’ dance (chorea), arc de cercle (in which the patient lies horizontal, face up, with a totally arched back), language impairment, animalization (the patient becomes a dog), machinization (the patient becomes a steam locomotive), delusions of persecution, kleptomania, loss of sight in this eye or that eye, restricted vision, taste, or smell, visual hallucinations, voices; every type of pseudotubercular lung congestion, headache, stomachache, constipation, anorexia, bulimia, alcoholism, debility, or trance that I have ever read about in the literature of hysteria—I can find all these in the reports of Louis Vivet. Yet a common thread among Vivet’s innumerable maladies issued from the hands of his doctors, and it is that which held the medical imagination, for a while.
Louis Vivet’s starting point in life is all too familiar, both then and now. Born in Paris in February 1863, he was the son of an alcoholic prostitute who beat and neglected him. By age eight, when his mother was working near Chartres, he became a runaway. From early childhood he had hysterical crises, as they were called, including spitting blood and brief paralyses. In October 1871, when he was not yet nine years old, he was convicted for stealing clothes and sent to a reformatory for children. After almost two years he was moved to a prison farm in northwest France (Haut-Marne). He stayed there for some nine years, but in mid-term, March 1877, he was scared silly by the sight of an adder (in later accounts the viper wrapped itself around his arm). That night was followed by convulsions, after which his legs were completely paralyzed. He behaved just like a paraplegic, but with no spinal cord damage at all.
After three years of idleness at the prison farm, he was transferred to an insane asylum about twenty miles south of his mother’s home in Chartres. The doctor in charge, Camuset, found him to be a delightful lad, simple but full of regret for his juvenile crimes. He was taught to be a tailor, a trade he could pursue while paraplegic. He was an apt student except that after two months he had an attack of convulsions lasting fifty hours. He woke up with no paralysis and believing he was still at the prison farm. He knew nothing of the insane asylum, paraplegia, the snake, or his new skills. He was violent, quarrelsome, and greedy; previously abstemious, he now pilfered wine. He then stole quite a lot of money (sixty francs) and the personal effects of an attendant, and escaped. He sold the clothes he was wearing, bought new ones, and was about to buy a train ticket to Paris, when he was captured, kicking and biting. During the rest of the time at the asylum he had various convulsive attacks, periods of local anesthesias, and contractures. But he got better and was released in the summer of 1881, aged eighteen. Camuset wrote him up as a case of dédoublement de la personnalité.10
Thus far, that is pretty much what he was. There were two characters, one of whom knew nothing of the other. The gentle personage was paraplegic, the violent one not. The criminal type had no memory of the events at the prison farm, the adder, and the subsequent paralysis. The only way in which Vivet failed to fit the prototype is that the extravagant violent character would count as the “normal state,” while the condition seconde was docile, pious, and dull—quite the opposite of all the standard cases, where the normal state is the inhibited one.
After being released by Camuset, Louis Vivet went home to his mother and then was off to Burgundy to work on a large estate that grew grapes. He soon fell ill, spent a month in the hospital, and was transferred to another asylum twenty-five miles away. His history was unknown to the doctor in charge. Vivet had ample crises of every conceivable sort, from complete paralysis to imbecility. He was strongly aware of a moral code, and if he did something impulsively would slyly cover it up by acting crazy.11 In spring 1883 he was declared improved. He was discharged and given some money to get home, but he did not quite make it. He spent three days in jail for a trifling theft, about forty miles from Chartres. We catch sight of him in a number of asylums; he spoke of Vaucluse and the Salpêtrière, of being treated by well-known doctors such as Lasègue and being hypnotized by Beurmann. He talked of roaming Paris in the company of a mate from one of his asylums.
He was again arrested for stealing clothes and other personal effects. Judged to be mentally retarded and epileptic, he ended up at Bicêtre, where he came under the care of Voisin. He had attacks of practically everything. Voisin attempted to transfer his symptoms by the use of magnets. The magnet had no effect at first, but later when Vivet realized the importance of the magnet to Voisin, the very sight of a magnet would make him switch states. Gold coins placed on afflicted parts caused him excruciating pain. Voisin put him into states of provoked somnambulism and conducted the usual tests of suggestion, getting the boy to taste numerous exotic wines and liquors, always from an empty glass; of course he got drunk. He was made to vomit. When it was suggested that he had gonorrhea, he at once picked up a chamber pot and tried to urinate, screaming in pain, cursing the woman from whom he had caught the disease. As Voisin aptly observed, “all of the usual arsenal of suggestions and provoked hallucinations was thus brought into play.”12
It is not quite clear when Voisin recognized that he had Camuset’s doubled personality in his care. I do infer from the texts that Vivet learned from Voisin of Camuset’s having made him famous for dédoublement. At any rate Vivet would sometimes be his quarrelsome violent self, knowing nothing of the adder, and sometimes he would be his docile self, paralyzed from the waist down. But these states were modulated by innumerable hysterical crises. One was what we would call schizophreniform, and endured for two months. Voisin used Azam’s terminology of a first and second state, but noticed some differences from Félida. The first state was the violent one, the second docile. But there were different versions of the docile state; for example, in one Vivet was previper and had no knowledge of the paralysis. But what most impressed Voisin was that Vivet’s periods in the second state coincided exactly with a severe contracture (but not paraplegia). Moreover, when hypnotized, but only when hypnotized, Vivet would assume “some sort of third state” in which he was sixteen and a half years old and knew of his life at the prison farm only before he had seen the adder. But Voisin did not conclude that this was a third personality, or even properly a third state to compare to states 1 and 2—for it was not spontaneous, but the result of hypnotism.
Vivet was subjected to a strange variety of treatments, including morphine, injections of pilocarpine (a botanical alkaloid; in Vivet it produced transfers of contractures), oil of ipecac to induce vomiting, and magnets on numerous parts of the body; but the only treatment that could halt an attack was pressure on the Achilles tendon or the rotulian tendon below the kneecap. He was repeatedly hypnotized. After a hypnotism session on 2 January 1885 he had a crisis and, once again, stole an attendant’s money and clothing—and escaped.
At the end of January 1885 Vivet enlisted as a soldier in the French navy, apparently with the intention of going to fight in Vietnam.13 He was posted to Rochefort, a longtime naval base on the Bay of Biscay, about a hundred miles north of Bordeaux. He was caught stealing clothes (why always clothing?). He was court-martialed but found not responsible and sent to the military hospital, where he fell into the hands of Bourru and Burot.
These two were fascinated by the transfer of hysterical symptoms by the use of magnets, metals, and drugs. They went to town on Vivet and quickly discovered they could move him from one state to another by the application of specific materials. Moreover, he was wonderfully responsive to drugs acting at a distance. Behind the head of Louis Vivet you hold a drug, and suddenly he begins to act as if he has taken that drug internally. This was indeed the topic of their first book in which Vivet was the major figure—not a study of multiple personality but a work subtitled The Action at a Distance of Toxic Substances and Medications.14
When Bourru and Burot first encountered Vivet, they said that the very first thing to do was to see the effect of metals and magnets on their patient.15 They experimented vigorously and obtained extraordinary results. The application of a substance would produce a new paralysis and/or anesthesia in a new part of the body. One of the possibilities was paraplegia, namely, Vivet’s state at the prison farm after he saw the adder. This was reinduced through the application of a magnet to the nape of the neck. Recall that in Camuset’s asylum, the loss of paraplegia was associated with amnesia for the viper; Vivet was docile and learned tailoring. When a magnet was applied to the nape of his neck in Rochefort, he not only became paraplegic but also recalled the adder.
Then comes the remarkable part. Various substances produced other hysterical somatic symptoms. It was as if to satisfy the suggestions of his doctors, Vivet had to respond to the metals, and, in addition, in his clouded or entranced mind, each new paralysis had to be associated with some part of his life, some set of memories and mode of behavior. Thus each metallic compound produced a new state consisting of a distinct somatic symptom and a character with memories of a distinct life-segment. Following Azam, Voisin had spoken of Vivet’s first and second states. In their first communication of 1885, Bourru and Burot spoke of states 1 through 8. In their book of 1888 they cut this down to six fully developed states, plus a large number of fragmentary ones. They had Vivet pose for photographs in ten of his abnormal physical states—“nervous states.” Each of these corresponded to a manner of behavior, general knowledge, and memories of a segment of life.
Thus plate 2 in the book is captioned “The Bicêtre state; complete paralysis of the left side of the body (face and limbs), 2 January 1884; twenty-one years old.” Now this is just a little misleading. The photograph was not taken on 2 January 1884. It is a photograph, probably taken in 1885, of Vivet in the physical state that symbolized 2 January 1884. This state was produced through the placement of magnetized steel on Vivet’s right arm, so the paralysis and anesthesia vacated to the left. A dynamometer was a usual test of the extent of a paralysis; in this state the strength in Vivet’s right arm was measured as 36 kg, and 0 in the left. He acted as if he were in Bicêtre; he had seen Voisin yesterday. He had no memories later than 2 January 1884 and none before Bicêtre except a fleeting glimpse of Sainte-Anne’s, which at that time served as the Paris general admission asylum. The magnet had transformed him from his first state, that of an arrogant, aggressive man paralyzed on the right side, to a gentle man paralyzed on the left. He spoke better, was polite, never used the “tu” form as he had just been doing, could read well and clearly, and preferred milk to wine. “This was not the same person (personnage) as before.”16
There are ten such photographs in the book, all taken, I imagine, during the course of a couple of days. Bourru and Burot had discovered that every mental state was associated with a state of nervous paralysis and anesthesia, and that they could induce each such physical condition by placing a substance on some part of the body of Louis Vivet. Transitions usually began, after induction, with deep breathing and spasms or convulsions. I should say that the sixth state (as counted in 1888; eighth as counted in 1885) was somewhat different from the others. It began with hours of tumult, convulsions, hallucinations. It was induced by soft iron applied to either thigh. The resultant personality remembered all of Vivet’s life except the paraplegic episodes. He had no paralysis, but his left side was hypersensitive.
I may be thought to exaggerate Bourru and Burot’s emphasis on the essential interaction of three ingredients: metallic substance applied to a specific part of the body, type of paralysis, and segment of life remembered. My point is that his doctors created conceptual space for the idea of multiplicity. There were many more fragments than the ten that were photographed. One day Louis Vivet went through what I suspect is the most elaborate spontaneous memory regression that took place during the nineteenth century. So far as I know, no one has recently paid any attention to it, but once it is noticed again it may become yet another part of the iconography of age regression therapists. So I had better set out what happened.
Louis Vivet was presented with a flask of gold bromide. He then fell asleep, and woke up over and over again, cycling through the following states:
(a) He wakes at age five in Chartres, living with his mother. His speech is childish, but sufficient for his age. He trails his right leg when he walks.
(b) He reawakens at age six and a half in Lève near Chartres. He manifests contracture of the left side; his right leg is extended, his arm bent, fingers clenched.
(c) He reawakens at age seven in Luysan, also near Chartres. He has contractures of the right side of the face, which hinders speech, and of the leg. His mother beats him. He begs for bread in an infantile voice.
(d) He reawakens in Chartres, aged eight. Here he is treated by a Dr. Salmon for eight months. He has contracture of the left arm, and of the right leg extended.
(e) He reawakens at the prison farm, aged thirteen, before he has seen the snake. He has not worked for six months because he fell ill on leaving a bath, and he has various contractures. There is a photograph of Vivet in this condition. He recalls that before the prison farm he was with a Mr. Bonjean near Evreux.
Bourru and Burot call this “a beautifully clear example of the spontaneous déroulement of several personality states, most of them unknown and which could be added to the states previously described.” They say these states were induced specifically by gold bromide. Do we have, here, the first detailed example of spontaneous age regression on the part of a multiple? Unfortunately, age regression was a standard trick of stage hypnotists from the middle of the nineteenth century.17 We cannot doubt that the practice was familiar to Bourru, Burot, and Mabille, intensely involved in avant-garde hypnotism as they were. And Vivet certainly got around; he should equally well have known of age regression from his asylums and from popular shows. I am not saying that he was deliberately faking. I say only that we can have every confidence that this way to be a somnambule was very well known to both Vivet and his audience.
What was up with Louis Vivet? Retroactive diagnosis would be preposterous. Anyone stating with confidence what was wrong with the man would thereby be playing the fool. We can at best read this complex and painful history in numerous ways. We can easily see him, for example, as a well-developed DSM-III multiple personality who dissociated early in life to cope with appalling conditions. My own take on this horrible life history is consistent with that but has a very different emphasis. As I see it, Vivet was in effect trained to make the correspondence between personality state and somatic symptom. In the first instance the reemergence of paraplegia and the docile second state was spontaneous. He was rewarded for that. Trivially, he stopped having to work and was in the end moved out of the prison farm, no mean achievement. More important, he was rewarded because he became famous, the subject of a much-discussed article by his doctor, Camuset. He fell into the hands of doctors fascinated with transfer of hysterical somatic symptoms by the use of magnets and metals. What better way to conform to their expectations, and hope for further reward, than to have the paralyses move, and with each movement to assume a different life-segment, mimicking what happened spontaneously in Camuset’s asylum? Vivet desperately wanted to please, to be loved, to be rewarded. I am not saying that Vivet worked this out. I say only that the environment in which he found himself was conducive to this sort of learning. Others will read the events differently.
Bourru and Burot completely subscribed to the connection between personality and memory. “The comparison of previous states of consciousness with present states is the relation that unites a former psychic life with the present one. That is the foundation of personality. A consciousness that compares itself with a former one is a true personality.”18
That had become a commonplace, already urged by the entire school of positivist psychology, although no one, I think, took quite such a simplistic view as Bourru and Burot. They cited Théodule Ribot on the memory. The belief that memory was the foundation of personality gave weight to the idea that we did not just see some six or eight or ten states of Louis Vivet, but at least six personalities and some personality fragments. Truly multiple personality, as I have said, had entered the language of psychiatry.
Bourru and Burot stated that their results should prove rich in practical applications. Vivet was transferred from the military hospital to the asylum at La Rochelle, twenty miles up the coast. Daily care was left to colleagues such as Mabille and Ramadier. Voison had been able to prevent or diminish attacks by pressure on a tendon. Mabille and Ramadier were more draconian. When Vivet was in a state of major crisis, they found it easy to recognize the approach of an attack by the sensitivity of the body part with hysterical somatic symptoms. They found that they could prevent the attack by tightly squeezing the man’s testicles. Then they induced somnambulism by pressing on the eyes, opening the eyelids, and rubbing the crown of the head. “To this extent, suggestion allowed his normal personality to return, and, as if by enchantment, to make the crisis and the majority of the symptoms disappear.”
Thus far, we do not notice any use of memory in the day-to-day treatment of Louis Vivet. But the correlation between life-segment and paralysis was used. Ramadier and Mabille used it to catch Vivet when he was cycling through his states. They could tell what mental state he was in by his paralysis. When he was in a physical state corresponding to his most “normal” personality, one would intervene and stop him there, like a clock. We are not told how the doctors intervened, but presumably as before, by testicular shock and hypnotic devices.19
Mabille and Ramadier were confident that they had established the intimate relation between personality states and nervous crises, that is, the various attacks of somatic hysterical symptoms. In the case of Vivet, at least, they never encountered a change in personality without the crises or preliminary somatic modifications. That was the big discovery: hysterical paralyses match memory segments.
Our authors also state that subjects such as Vivet “are unhappy because of lacunae that crop up unexpectedly in their memories after a crisis; we believe that it will be possible to revive these numb memories.” Today that may sound like recovering dissociated or repressed memories. It may sound as if our doctors foreshadowed the cathartic therapy of Janet, Breuer, and Freud. Absolutely not. No dynamic psychiatry was in view. The patients were, in an ordinary way, unhappy because of big gaps in their memories. Bourru and Burot thought they could locate, by noting the somatic correlates, a relatively normal state, corresponding to a fairly continuous life-segment; then, perhaps using magnets and metals, or perhaps using the more brutal technique of Mabille and Ramadier, they could wake the patient up in the relatively normal state.
After what is, in contrast to my own account, a mercifully brief description of what his doctors did to Louis Vivet, Alan Gauld concludes by noting that “despite this meddling he left [their hospital] in 1887 much improved.” How do we know? F.W.H. Myers wrote that “in 1887 … Dr Burot informed me that [Vivet’s] health had much improved, and that his peculiarities had in great part disappeared.”20 Since the symptoms had remitted twice before, and since Vivet had twice before been discharged from asylums as relatively cured, Burot’s statement may be taken at face value. If the doctors really did make a grab for his private parts every time an attack was in the offing, you can see why he may have wanted out, fast. I have no idea what happened to Louis Vivet. Probably he went back to stealing clothes. My guess is that the next time he was caught he preferred the criminal justice system to the mental health system.
Azam briefly discussed Louis Vivet. “I remain convinced,” wrote Azam in a sentence so tortuous that I suspect he did not want to write it, “that if this patient, rightly held to be ill with hystero-epilepsy, had been studied from the point of view of sleep, it would have been found that in his childhood, troubled by misery and vagrancy as it was, he was a somnambule, and that his second states were only exaggerations of his attack of somnambulism.” Note the plural: Azam grudgingly went halfway to the position that there was more than one alter, but no further. On his view there is still, first, the normal state, and then second states that are all somnambulic, going back, it now appears, to childhood. Oddly, Azam found the present-day thesis of childhood origin a natural one, but he was disinclined to think that there were more than two personalities.
As Crabtree said, Bourru and Burot brought out the connection between specific personalities and specific memories. This was a further tightening of the connection between multiplicity and memory. But notice that only when we have multiple personalities does this connection become so critical. If there are only two personalities, the other personality is simply the other. But if there are several, then you need a way to tell which is which. Bourru, Burot, and Louis Vivet provided a beautiful way to identify personalities. Each personality had its three-part signature: a memory segment, a metallic compound, and a characteristic bodily infirmity.