Allen's Law of Admissible Structure

Version 2 clarifies the formal status of coherence and strengthens the abstract without changing the law or its mathematical content. This paper states a universal law governing admissible structural updates. The law asserts that an update is applied if and only if the resulting structure is coherent; otherwise, the structure remains unchanged. The statement is fully domain independent and requires only the primitives of structure, update, and coherence. The law is presented in three equivalent forms: a predicate form, a scalar functional form, and a certificate (verifier) form, allowing both abstract and operational interpretations. This paper serves as the concise law statement derived from the theoretical framework developed in Allen’s Universal Equation of Admissible Structure. The formulation is intended as a reference object for citation and application across domains where admissibility can be defined in terms of coherence.