Abstract
Paper XVI established source-term locality: a quantity representing unused alternatives decays under optimization and persists only through a source term whose position — inside or outside the optimizer's control set — determines whether collapse is robust or contingent. This paper isolates the structural reason such a source term can be irreducible.
The core object is an asymmetry between two kinds of dependency. Processing — whether a system computes what it claims — can in principle be made arbitrarily verifiable. Certification of reality — whether the external fact a rule depends on actually obtained — cannot be made self-verifying, because a verifier that certifies a world-fact needs a certifier in turn, and the regress terminates only by accepting one anchor as trusted-unverified. Chain length (the number of editable links between an institution and its nearest fixed invariant) is a coordinate on this asymmetry, not a separate thing.
From the asymmetry follows a relocation invariant: automating a coordination boundary relocates its irreducible certification link upstream but does not remove it. The invariant is scope-bounded. It holds for world-coupled coordination — coordination that must answer to some fact outside itself — and demonstrably fails for self-referential coordination (pure convention), where the rule and the practice are the same thing and there is no external fact to certify. Governance is world-coupled by construction, so the invariant applies to it; pure convention escapes it.
The result is not a theory of institutional persistence and not a universal law of adaptive systems. It is one bounded structural regularity, its domain of validity stated, its evidence base and its limits recorded honestly. The evidence is concept-isomorphism across independently-formalized disciplines; it is strong on "these fields formalize the same shape" and weak on "the shape is true of the world," and the paper claims no more.