The Myth component of 📝MythOS is what your knowledge becomes once other people carry it. Where the 📝Mouth broadcasts — one voice reaching many, and still yours to maintain — Myth circulates. A memo forked into someone else's library becomes part of their 📝Memory, and is therefore readable by their 📝Mind. Knowledge stops compounding only for its author and begins compounding for everyone who takes it up.
In practice, Myth is the layer of communities, forking, public memos that other people's AI collaborators retrieve and cite, and the courses and gated collections readers pay to enter. Because not everything should travel, the layer depends on a real access model rather than an all-or-nothing publish switch: selective permeability is what makes it usable rather than merely open.
A system that stops at Mouth is still a closed loop — you speak, and the knowledge remains yours to carry. Myth is the layer that decides whether the other three outlive you.