Jung’s complex theory
Morton Prince’s famous account of the Beauchamp case (The Dissociation of a Personality, 1905/08) has an honored place as the prototypical American description of multiple personality. The authors of more recent and popular accounts, such as The Three Faces of Eve and Sybil, have used Prince’s book as a guide to observation and treatment-perhaps ill-advisedly. For Prince was not diligent at “keeping his cultures pure,” as Janet recommended; he failed to notice that his words and actions might be suggesting the course of his patient’s behavior and shaping her memories. But he understood the main point:
The dissociated and multiple personalities are not novel and freak phenomena, but are only exaggerations of the normal and due to exaggerations of normal processes, and it is for this reason that they are of interest and importance. For, being exaggerations, they accentuate and bring out into high relief certain tendencies and functional mechanisms which belong to normal conditions and they differentiate mental processes, one from another, which normally are not so easily recognized.