The Purpose Of A System Is What It Does.

There is an objective answer to any question about your system.

Your existence must be peer diagnosed to be real. Every plural-looking experience must be labelled as soon as possible with the appropriate community terms (regardless of whether the receiving party wants those labels) because the labels make it real. These labels and diagnoses are objective truths about reality that define everything about how your system works.

Your existence must fundamentally be DID or OSDD. Maybe UDD, temporarily, until you get a DID diagnosis. There are no other diagnoses relevant to plurality, and there are no experiences outside of diagnoses. If you have a diagnosis, then you can never have nothing in common with spiritual plurality.

Maybe you have introjects, soulbonds, or visitors- which, of course, must have either have come from inside your head or come from other universes entirely, arriving in your head completely unbidden. There are no other explanations or forms of spirituality that intersect with head sharing. The outside of your head only comes inside in specific, socially accepted ways.

"But I know that spiritual experiences exist"- okay, what are they? How many experiences can you name that aren't fictional visitors walking in from another universe? When was the last time that you saw someone talking about other forms of spiritual plurality without being buried under harrassment for being honest about their lived reality?

There's a good bit more that borrows from medical perspectives of plurality in the community's typical expectations for systems, and I think it's worth mentioning more of it while we're on the topic:

You have a Host who is supposed to do all of the talking about anything important because they are the Normal Person. Everyone else's feelings, opinions, etc. are disposable compared to the Host's because they are the Fake People, the crazy nuisances, the disruptions to the Host's normal life. Your life revolves around your Host and only includes things that they totally agree with. Everyone else must always pretend to be them even if it makes them miserable.

Your alters should be rigorously inspected, categorized, and changed to fit the Host's life better even if they'd rather have nothing to do with any of it. They have no right to privacy or autonomy if their desire for it bothers anyone else. They will often be spoken about as collectible objects, nuisances bothering you for fun, or convenient helpers who vanish as soon as you stop benefitting from talking about them. They are not allowed to complain about this pattern.

Every headmate has prescribed roles that they can never change or step away from. These roles are rooted in filling specific mental niches- every headmate has a Purpose for existing regardless of how they got here in the first place. Headmates are their functions above all else. (And, of course, all of those functions serve the Host in some way.)

Your experiences never really change, and you never really grow out of old understandings of yourselves. You get it right once and then you're done figuring it out forever. Categories never overlap or shift.

I could go on! Your system should be a certain size, act a certain way, agree on certain things, have certain kinds of knowledge and lack other knowledge, and flawlessly fake being one consistent person if you want to be taken seriously. Should be, should be, should be.

It's bullshit. None of this has to be true, and we don't have to give it any real weight when defining how we want to understand ourselves if it's not serving us. We are allowed to define ourselves and live that truth.