Multiple Personality

Early History

Multiple Personality Disorder (MPD) or, as it is now known, Dissociative Identity Disorder (DID) was one of the earliest studied psychological disorders.

The first serious study of DID was undertaken by the Frenchman Pierre Janet. In 1883, a local doctor introduced Janet to his patient, Léonie. Léonie was a 45 year old woman with three quite separate personalities.

While Léonie’s first personality was timid, sad, and serious, her second, ‘alter’, personality was completely different. She was a lively good natured joker. More than that, her second personality refused to accept that she was the same person as the first, saying, “That good woman is not myself…she is too stupid.” [1]

Léonie’s third personality was a slow moving and serious person. She also refused to accept that she was the same person as the first personality saying that she was a “good but rather stupid woman…and not me” [2]. She also refused to accept that she was the same person as the second personality saying “How can you see anything of me in that crazy creature?” [3]

The three personalities didn’t have the same knowledge about each other. Léonie’s first personality knew only about herself and nothing at all about the life and times of the second and third personalities. Her second personality knew about herself and also all about the activities of the first personality (but nothing about the third). And her third knew about herself and all about the lives of both other personalities.

Given that the different personalities could control the body at different times, and given the different knowledge the three had of the others’ activities, Léonie’s life was complicated. For example, her first timid personality, ignorant of all events that took place when the second was in control (such as socialising with men), would be overwhelmed with embarrassment when she was approached in the street by male friends of her second personality. Her second personality would write letters to her friends. But if the first personality discovered them before they were posted, she didn’t know who had written them and so would destroy them. This meant that her second personality had to hide her letters from her first personality.

Sometimes Léonie’s second personality would go out to places and then hand back control of the body to her first personality. This left the first personality totally confused as she didn’t know where she was or how she had gotten there. But still, somehow the three were living a life together.

Other leading figures in Europe such as Jean-Martin Charcot, Frederick Myers, and Charles Richet, all personally examined Léonie and confirmed Janet’s observations. And others in Europe also published on the topic of multiple personalities including Alfred Binet (of IQ testing fame) who published On Double-Consciousness [4] in 1890 and Alterations of Personality [5] in 1896.

Janet described the process of the splitting of consciousness as disaggregation (later translated into English as dissociation). Janet described the different personalities as successive existences which he believed to be split-off parts of the personality which were capable of independent life, identity, and development. He thought that the splitting of a personality came as a consequence of real trauma and thought that treatment should proceed by first bringing into consciousness the split-off memories and emotions, which would then be subjected to further therapy.

Also in Europe, in 1895 Josef Breuer and Sigmund Freud published their book Studies on Hysteria [6] which presented case histories of several female patients. Most of these patients had been sexually abused and all displayed dissociative symptoms. Included in this book was the patient “Anna O.”.

Anna O. was a very important patient for Freud, as she represented the founding patient of psychoanalysis. She was also a patient with multiple personalities. Breuer wrote that Anna O. had “two separate states of consciousness” [7]. In one of the states her personality was relatively normal, but melancholy and anxious. She would complain that she ‘lost’ time. That is, for her, there were periods of time in which she had no memory of the events that had happened. In the other state her personality was ‘naughty’ and would abuse people and throw things at them.

Breuer wrote “It is hard to avoid expressing the situation by saying that the patient was split into two personalities of which one was mentally normal and the other insane.” [8] He also described a third personality who appeared not to be actively involved, “a clear sighted and calm observer sat, as she put it, in a corner of her brain and looked on at all the mad business” [9]

Across the Atlantic, William James the leading American psychological theoretician saw the observations and work of Janet as very important and discussed Janet’s work extensively (as he did elsewhere) in the 1896 Lowell Lectures [10].

Another influential figure in the United States was Morton Prince who, in 1905, published The Dissociation of a Personality [11] presenting the case study of Miss Beauchamp (pronounced Beecham), a woman displaying at least four distinct personalities. In the following year Prince founded the Journal of Abnormal Psychology – an important journal still over a century later - with the very first paper in the first issue written by Janet. Prince described the scope of his journal to include “alterations of personality, multiple personality, dissociation of consciousness, [and] subconscious phenomena” [12].

But DID was considered to be something more important than simply an unusual and very interesting disorder. If the human mind can break down into a set of largely independent personalities, then many believed that DID tells us something very important about the human mind.

Firstly, DID was considered by many to be important in understanding other psychiatric disorders. Charcot, the leading figure in Europe, at the time, proposed that in hysteria the stream of consciousness broke up into elements [13], and Binet thought a doubling of consciousness was common in a number of psychiatric disorders [14]. In a similar vein, Freud and Breuer, thought a splitting of personality occurs to a “rudimentary degree in every hysteria” [15]. And in 1906 Prince published his paper Hysteria from the point of view of dissociated personality [16] in which DID provided a frame of reference for other disorders.

Secondly, DID was considered to be the key to understanding the normal mind. In this respect James thought DID represented a “gold mine” [17], discussed DID extensively in a theoretical chapter on the consciousness of self in his seminal Principles of Psychology [18], and summarised the first of the 1896 Lowell Lectures with the statement “the mind seems to embrace a confederation of psychic entities” [19].

If multiple personality is so important in understanding the normal mind, and in understanding psychological disorders, why isn’t it also central to the teaching of Psychology today in universities?

The answer is one man – Sigmund Freud.

  1. James, 1890a, p. 366
  2. James, 1890a, p. 366
  3. James, 1890a, p. 366
  4. Binet, 1890/1977
  5. Binet, 1896/1977
  6. Breuer & Freud, 1895/1983
  7. Breuer & Freud, 1895/1983, p. 76
  8. Breuer & Freud, 1895/1983, p. 101
  9. Breuer & Freud, 1895/1983, p. 101
  10. Taylor, 1982
  11. Prince 1905/1978
  12. Allport, 1938, p. 4
  13. West, 1967
  14. Binet, 1896/1977
  15. Breuer & Freud, 1895/1983, p. 63
  16. Prince, 1906
  17. Murray, 1956
  18. James 1890b
  19. Taylor, 1982, p. 35

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Allport, G.W. (1938). The Journal of Abnormal and Social Psychology: An editorial. Journal of Abnormal and Social Psychology, 33, 3-13.

Binet, A. (1890/1977). On double consciousness. Washington, DC: University Publications of America.

Binet, A. (1896/1977). Alterations of personality. Washington, DC: University Publications of America.

Breuer, L., & Freud, S. (1983). Studies on hysteria. New York: Pelican Books. (Original work published, 1895).

James, W. (1890a). The Hidden Self. Scribner's magazine, 7(3), 361-374.

James, W. (1890b). The Principles of Psychology. New York: Holt.

Murray, H.A. (1956). Morton Prince: Sketch of his life and work. The Journal of Abnormal and Social Psychology, 52, 291-295.

Prince, M. (1905/1978). The dissociation of a personality. New York: Oxford University Press.

Prince, M. (1906). Hysteria from the point of view of dissociated personality. Journal of Abnormal Psychology, 1(4), 170-187.

Taylor, E. (1982). William James on Exceptional Mental States. The 1896 Lowell Lectures. New York: Scribner's.

West L.J. (1967). Dissociative reaction. In A.M. Freeman & H.I. Kaplan (Eds.) Comprehensive Textbook of Psychiatry (pp. 268-288). Baltimore: Williams & Wilkins




What is DID?

Early history

Freud and DID

Details of DID


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