Every social constellation necessarily defines an out-group. This creates an unresolved tension with centaur-religion (LEO-C01): either centaur-religion accepts it will have an out-group, functions as a meta-constellation for constellations to interact rather than a constellation itself, or demonstrates that the structural necessity of boundaries is wrong. The closest historical parallels for boundary-minimal constellations - Hellenistic cosmopolitanism, Enlightenment universalism, scientific community norms - all either developed de facto boundaries or dissolved.

Strongest rival: Boundaries are historically common but not structurally necessary - online communities, scientific networks, and cosmopolitan identities maintain cohesion with permeable boundaries and multiple overlapping memberships rather than sharp in-group out-group divisions