Biological Systems: Admissibility, Identity, and Structural Persistence

This paper extends the Paton System into the domain of biological systems, treating living organisms as constraint-regulated persistence structures operating within bounded admissibility corridors. Building upon constraint primacy, the Boundary–Relation–Persistence (BRP) framework, and the Lowest Admissible Configuration (LCD) under strain principle, the work formalises biological identity, homeostatic admissibility, structural compression, and collapse conditions. Biological systems are modelled as multi-scale regulatory state machines whose survival depends on preserving an invariant Biological Identity Datum within a constrained configuration space. Under increasing strain, regulatory degrees of freedom compress toward a minimal viable configuration; if that configuration becomes inadmissible, pathological transition or organismal failure follows. The framework is descriptive rather than prescriptive and introduces no new ontology.