Thoughts on "Everyone is Plural"
In the context of psychology, systems theory is the idea that people are influenced by surrounding systems such as society, families, and the environment, and that the different parts of these interactions should not be looked at in an isolated manner. There have been many applications of this idea, ranging from family systems therapy to cybernetics. Most relevant to this article is the idea that all people are systems within themselves: people are made of parts/subpersonalities regardless of plural status and experience a complex interplay of chemical, mental, and physical processes that add up to their experience of self.
Unsurprisingly, systems theory has become moderately popular among plural groups. It reflects their reality and is thus an easily accepted framework to describe the mind. A framework that validates the existence of parts within people is naturally going to fit in well with those who are more than one person to begin with. Some have taken it to mean all people are plural, claiming that no one is really singular to begin with and that parts of self should be more emphasized in psychology. The slogan "everyone is plural" has started to crop up for better and worse.
There are some upsides...
It provides tools for understanding
For singlets that have struggled to understand their own behavior, giving them awareness of their parts may be helpful. Care must be taken not to encourage fragmentation if it would be detrimental or unwanted, and it's important to ensure it remains a choice, but presenting the tools of a plural framework gives people another option for making sense of their internal experiences should they choose to take that approach.
Some singular people do find it helpful to recognize their parts even without seeing them as separate. Internal Family Systems therapy is an example of using this framework to one's benefit, and it was designed for singlets. It can be a useful tool for growth if it suits the person. One or two other forms of therapy also utilize this kind of model- Developmental Needs Meeting Strategy (DNMS) being another example. These modalities don't work for everyone, but they can greatly help those that find them useful.
It spreads knowledge of plurality
Plurality is still a relatively unknown minority experience. Most of those that do know about it are either plural themselves or fans of horror movies and clinical psychology, meaning that the public understanding of plurality is limited. Many people don't know about plurality at all and have never considered the notion. Talking about plurality within the self is a jumping point for discussing plurality in general and may help spread awareness. As a side effect, this might make a few people realize they are plural. It could also help increase acceptance. If everyone has parts within them, then it's less of a leap to multiplicity of the mind that goes beyond typical parts. That said, there are better ways to spread understanding without asserting that everyone is plural, which may cause misunderstandings in the same way that people confuse depression with feeling a little sad or OCD with liking organization. Everyone has parts in some sense, but not everyone fits a framework of being more than one person.
It creates another framework
There are few academically accepted explanations for plurality. Most of them involve extensive childhood trauma and do not account for the experiences of systems that do not have a trauma history. The idea of everyone having an internal system does account for these experiences- they're simply more separated versions of normal experiences that could have developed naturally. This framework provides a way for these systems to exist that mostly fits into modern psychology's understanding of identity and self, giving them a chance for recognition. Unfortunately, it may also provide a way for academia to dismiss these experiences entirely because they're either an unusual expression of a normal experience or can be declared to be disordered.
...but the problems outweigh the benefits.
It's not the point of systems theory
Systems theory is very clear that the point is not to make people all about their parts. That's an entirely different viewpoint known as reductionism, which believes that things should be understood through the individual parts that make them up. The two viewpoints are often regarded as opposites. Systems theory suggests that while there are parts, it's the interplay between them that should be addressed, and ultimately it's about putting individuals into context and looking at their situation from a broad perspective rather than taking a magnifying glass to one part of it. It's a very sociological view of psychology. In the context of internal systems, it is at most about understanding and adjusting the roles of one's parts in relation to their whole self so that the whole might function better; the self outside of the parts is emphasized (so much so that it gets a capital letter in IFS). For some, even this approach isn't feasible, as they do not experience their parts as anything other than them. A systems view of an individual is not about further fragmenting that self to approach the parts in these cases. Indeed, the emphasis even in more fragmented internal systems is on coming together and cooperating seamlessly as a person rather than amplifying individual parts.
The language is in opposition
The words "plural" and "singlet" exist for a reason. If everyone is plural, then there are no singlets; despite this, there are singlets. Even if singlets have parts, their experiences are different from those of plural groups to the degree that a different word was coined for them. It could be argued that everyone is only plural in a sense, but at that point it becomes more about asserting a belief than referencing reality. Similar rhetoric is used to support the beliefs that autism isn't real, that someone isn't really depressed, and to support the logic that something is or isn't real because traits of that thing can be experienced by the general population now and then. They are not reliable proof. Not everyone is a system. Not everyone needs or wants to recognize their parts, and even out of those that want to, not everyone can. It's a common problem in Internal Family Systems therapy to be unable to pick out one's parts, and that mode of therapy is not helpful or possible for everyone as a result. If everyone were truly plural, this would be a non-issue.
It dilutes the meaning of plurality
Plurality encompasses all experiences of being more than one person. It's already a broad label, which is a good thing for including diverse experiences, but it is possible to go too far. Even if a singlet has parts, their experiences do fit into the singular norm and they do not consider themselves to be more than one. Claiming that they're plural means rewriting the definition of plurality to include all experiences of the self rather than the relative minority of not fitting into singular experiences, which would make the definition so broad as to no longer be useful. If everyone is plural, then functionally, no one is, and other words are then needed to describe the minority experience of being more than one in a way deviating from the norm.
Not everyone has plural experiences
Semantics and language dilution aside, not everyone experiences themselves partwise or experiences significant fragmentation of identity. According to the National Alliance on Mental Illness (NAMI), only 2% of people are diagnosed with a dissociative disorder. This by definition entails some fragmentation within the mind, though not necessarily a fragmentation in identity. 2% is not a large number, and perhaps too small; but even if every mentally ill adult in the United States of America were to experience themselves as having significant identity fragmentation, that would only be 20% of the population. While there are no statistics on how many non-disordered people experience themselves partwise more than as a whole, I doubt it would add much to this percentage. After all, plurality in any sense is still regarded as a strange, alien idea by the majority of people even when presented as being parts rather than people. If experiencing oneself as parts were the majority experience, this would be much less of an issue.
Singular people are more likely to relate to parts as an abstraction rather than a literal reality. I've spent a lot of time asking people about their minds to better understand different experiences of consciousness at this point, wondering what made singular people different from more unified plurals. Plural groups that work closely together and share an identity tended to view their parts as a literal experience of self. Their parts were concrete entities in their mind with distinct agency and presence, and they often took precedence over the shared self. In contrast, singular people viewed their parts more as a metaphor or abstraction, if at all. They did not see them as concrete individuals and at most viewed them as aspects of themselves that were emphasized at different times. They did not experience these parts as having any sort of agency or individual agenda. Some were even hurt by therapists trying to emphasize their parts (as in Internal Family Systems therapy, or IFS), finding that it worsened pathological dissociation to try looking at themselves that way. Singular people were far more likely to emphasize their whole self and to believe that any fragmentation within their self would be a step away from healing. Plural groups tend to believe that it is perfectly possible to be mentally healthy without being a singular, unified individual rather than seeing it as pathological, instead seeing dysfunction between their system members as the true pathology (a view I am inclined to agree with in the context of one who is already plural).
It disrespects personal choice
Referring to all people as plural disrespects individual experiences of self by ignoring one's views of their internal structure. Saying that someone who regards themself as singular is actually plural comes across as willfully ignoring their experiences in favor of one's own ideas. This person does not regard themselves as being more than one. Claiming that they're really plural is forcefully pushing a label and experience they do not want at them. It's like saying that someone is actually a carpenter when they work in plumbing. On a certain level, the professions are similar, but saying they're equivalent is untrue even if a plumber might be helped by knowing carpentry.
This would be less of an issue if people in the plural community didn't tend to assume everyone is plural the moment some degree of identity fragmentation or fluidity is mentioned. Identity changes can happen for all sorts of reasons without it being plurality. BPD, C-PTSD, bipolar, psychosis, genderfluidity, kin shifts, code-switching, masking, and more can all cause alterations in identity and self-perception, yet they aren't considered to be plural experiences by most and usually aren't enough evidence for having a system without there being more to it. Even a singlet's ordinary parts sometimes get this treatment. In some cases, treating these experiences as plurality can be outright harmful to the person; at best, it's unhelpful and they might be better suited by other frameworks that are rarely offered in lieu of convincing the person that they're actually plural. If they are plural, that's something they'll figure out for themselves. It's better to present a rounded set of ideas and let people form their own conclusions one way or another.
Is everyone plural?
It's inaccurate to describe everyone as plural. Yes, people are not monoliths. Minds are incredibly complex things that are often subdivided into parts and aspects, even in singlets. The key is that at the end of the day, singlets do not usually relate to plural experiences, and vice versa. Even medians who feel their parts are more an abstraction than literal do not fit into the norms of singularity. A singlet's parts are not felt as having agency separate from them. A system's parts have that agency. Plural groups tend to experience their parts quite literally and often find they function better after recognizing them. The majority of people consider themselves to be one person, and plurals are in the minority and regarded as disordered, dangerous, broken, or simply alien. If everyone were plural, then plurality would not be such a polarized and stigmatized idea in psychology or the public eye. I could go on. Point is, claiming all people are plural disregards this difference in experiences along with ignoring personal experiences of self. The word "singlet" exists for a reason.
Do recognize that people are complicated. Don't push plurality on everyone or claim everyone is actually plural. Let people decide that for themselves.