Mason argues the importance of recognizing and studying alternating personalities. He describes the awareness of the secondary personalities for each other and the primary personality, using the case of Madame B. to illustrate. The author identifies conditions in which the secondary personality has been observed: 1) spontaneously, 2) under hypnosis, 3) while asleep, and 4) as a result of pathologic conditions of the organism. The origin of personality as either a "product of a power inherent in nature" or "as an expression of organism" is discussed. The author concludes with consideration of the legal accountability of persons with alternating personalities.
Dr. Ward discusses the case of 13 year old Mary Parker. Mary suffered from the measles at age 7, and epileptic attacks started at age 12. Various remedies, such as bleeding out and leeches are tried on Mary, none of which work. Mary's ailments increase to include headache, pain and pressure on her left side. She eventually begins to alternate between delirium and a sound state of mind. Mary's symptoms disappear with the onset of menses. It was concluded that Mary's symptoms were connected to epilepsy, but were hysterical in origin.
The author discusses cases where the duplex personality of several different patients has been brought out with the use of hypnotism. Mason’s conclusion is that the second personality would have perceptive powers beyond the main personality. Clairvoyance is an attribute of this second personality and hypnotism is a way of bringing out this second personality in a controlled setting.
Dr. Myers reviews multiple cases involving altered personalities. These personalities have been brought on by a variety of means, including dreams, drug use, physical disturbance, epilepsy or hypnotism. Some of the cases involve automatic writing. Dr. Myers discusses each of these cases briefly with an emphasis on the differences between the conscious and unconscious self.
Dr. Mitchell discusses several well-known cases of multiple personality, including the cases of: Ansel Bourne, Felida X, Mr. Hanna, Miss Beauchamp, Louis V, Mary Barnes, Madame B, and Milly P. The doctor then goes on to discuss how these secondary personalities can be formed and how it is possible for one personality to not be aware of the other personality. Dr. Mitchell takes on the view of these patients having co-conscious personalities, his reasoning is discussed in depth.
Two cases are covered by Dr. Myers. The first case is of Louis V. He suffered from epilepsy, hysteria and paralysis after a great fright from a viper. His memory would occasionally relapse back to a previous time period. Later in life he would oscillate back and forth between two personalities. Each personality seemed to be controlled by a different side of the brain. The second case is that of Felidia X. She suffered from the presence of a second personality. She was able to function in both of these states due to being put into a hypnotic trance. Dr. Myers compares the two cases on the grounds of morals vs. biology.
This is a clinical case presentation of a young man, described as being very suggestible, hypochondriacal, and without motivation. The symptoms began after contracting typhoid fever in the Spanish American war, and after a head injury. The man traveled to London and South Africa in this alternate personality. He also became unaware of his surroundings and did not recognize his doctor, confusing him with a not very friendly acquaintance. The patient is described as being very amenable to hypnosis which had limited effects in controlling his alternate state.