Hey anon. Thanks for sending us this question.

A person I know who I usually perceive as pretty knowledgeable about psychological stuff keeps saying systems aren’t a thing because system members can’t communicate with each other, so they can’t form a system, as they stay “dissociated” from each other basically.

Your friend is wildly misinformed.

Even the staunchest “DID only” plural in the community would disagree with this position.

Almost all plural systems of every type and origin communicate between members to a greater or lesser degree.

For systems who are in therapy for disorder one of the major goals of care is to foster more and better communication between system members.

“Dissociation” doesn’t mean what your friend thinks it means. Dissociating, actively or passively, doesn’t mean you are necessarily unaware.

It sounds like your friend hasn’t researched the state of plurality in the psychological community since the 1960s.