Something that comes up frequently in conversations we’ve heard about plurality is the idea of a body “core”, and tangentially, a body “mask”. (These are just our terms, but the concepts are pretty widespread.)
The body core refers to the part of the system that seems to be shared in the body and its brain. Not all systems have this, but many do. This includes a shared memory, shared skills (like driving), and so on.
The body mask refers to a part of the body core which provides a neutral identity for its exterior, when it’s not in explicit plurality mode. (Bear with me, I am a computer nerd. These are the terms that make sense to me.) Essentially, most plural systems have two modes they run in.
Mode #1 is stealth mode. In this mode, one or more members of the system sit behind a mask and drive the body, pretending to be a singlet. They will answer to a common name (often not the name of anyone in the system), use the right pronouns (“I”, not “we”), and often take on a whole different set of body language, mannerisms, and speech patterns (including accent, which is often modelled after the body’s native language and accent).
Mode #2 is plural mode. In this mode, the people the system are interacting with are aware of its plurality, and each fronter is able to be themselves in full, complete with their own name, speech patterns, etc.
For us, we call the body core “BodyOS”. (Did I mention, nerds? It’s only going to get worse.) For us, BodyOS is made of two parts, much like a real OS. It includes a lot of functions for us, including a body mask we can use as needed, and of course the normal things as I mentioned above, like the ability to drive.
BodyOS also includes something akin to an operating system kernel. It is not a systemmate, but it can front when no one else can. (Mind you, it is not very sociable.) It is capable of assisting in switches, and it is also capable of booting someone out if they are unstable. (We are depressive, it happens.)
Why is this stuff important? Well, it is always important to know how your system works. And if it’s anything like this, it is also important that you keep track of where the body boundaries are, and not let it encroach upon your space. This is really a problem for some systems who have to display the body mask all the time. It’s easy to method act your way into an unreal sense of depersonalisation, and to even start to doubt who you are. It’s important to have some down time from that — time online doing things unique to you and so on, preferably interacting with people in “Mode #2” in person, on Skype, whatever.
It’s good to remember who you are.
I also find it useful to “pull skills” into the core when possible. What does this mean? Well, if one person learns how to paint, the others may not necessarily know how to paint right away. Even if they know the basic ideas, it doesn’t always feel natural. The more systemmates who do something like painting, the more it becomes a core competency, and in our experience, people who haven’t tried it are more likely to succeed.