(GC-arc5) Governance, Temperature, and Recovery: Why Diversity Requires Structure Across Biology and Society.

Complex adaptive systems must generate diversity in order to function, yet unboundeddiversity undermines control, recoverability, and long-term stability. In biology, this tensionis exemplified by somatic hypermutation and germinal-centre dynamics, where aggressivediversification is permitted only within tightly governed spatial, temporal, and regulatoryconstraints. More generally, similar trade-offs recur across medicine, technology, and socialorganisation, where systems operating under finite capacity face abrupt transitions betweenstable adaptation and pathological collapse.Here we synthesise immunogenetic analysis, systems theory, and non-linear dynamics toidentify governed diversity as a general condition for survivability. Building on ridge-basedstability analysis and empirical signatures such as variance amplification, delayed recovery,and hysteresis, we show that loss of function frequently arises not from error, intent, oroptimisation failure, but from exceeding structural limits on governability. This framingdistinguishes adaptive instability from subversion, and failure of control from failure ofpurpose.Across scales, survivability emerges from a shared control geometry comprising four pil-lars: diversity generation, compartmentalisation, bounded coupling, and recovery. Germinalcentres provide a concrete biological instantiation of this geometry, while parallel constraintsshape clinical intervention, technological governance, and population-level resilience. Thesynthesis reframes disease, fragility, and systemic instability as consequences of operatingbeyond governable regimes rather than as deficiencies of intent or design.Taken together, these results establish governed diversity under finite regulatory capacityas a cross-domain law of survivability, linking immunity, medicine, computation, and society.