This page describes the causes of plurality.
To put it simply, there is no known single cause of plurality. It's a phenomena that takes place through a wide variety of experiences, and due to heavy stigma both in the psychological field and society as a whole, it is rarely investigated. Systems are often left out of the research process as well in favor of a strictly medicalized singlet approach that has been widely frowned upon by the community at large because it leaves so little room for personal experiences from those with or without diagnoses. Being plural is not inherently medical since the experiences of systems are so vast and differing. Both those with complex dissociative disorders and those without them remain excluded from research about their own lives, making it much harder for them to express their experiences.
For many systems, the root of their plurality stems from childhood trauma. These systems will often be diagnosed with complex dissociative disorders as a result of their symptoms. The prevailing theory explaining this is the theory of structural dissociation which describes every person as starting out with different states. Those without significant trauma will see those states combine into a single sense of self, but in cases of severe trauma, the stress interrupts this process and leads to the creation of alters. The theory of structural dissociation is often helpful for those with complex dissociative disorders, but it may not be as valuable to those who fall outside of the CDD spectrum.
Many people believe that the only cause of plurality is trauma in early childhood. This is not the case, as there are many other systems that experience other types of plurality that were not formed under these circumstances. Systems that did not form due to childhood trauma have existed for decades, and there is widespread evidence of their presence as well. This misconception is damaging to plurals because it encourages the concept of a single exclusive experience despite the wide variety of ways that systems live with their plurality. There are many systems who did form due to childhood trauma--and this is certainly a common cause of plurality--but it is not the only way of being plural. Systems who experienced trauma at the crux of their formation are just as valid as systems who do not cite trauma as their origin, and the community should band together instead of pushing each other apart.
In general, there is no single cause of plurality. Systems have defined their plurality as being caused in a wide variety of ways, and they know their own experiences best. Whether they came from childhood trauma or not, they deserve respect. No one experience is superior to another. All systems are more than one, and that is the common thread that links us all even with individual differences and intricacies.Â