The First Semantic Consistency Layer

The origin of life remains unresolved. Contemporary origin-of-life research has proposed several partially overlapping explanatory frameworks, including RNA-world models, autocatalytic reaction networks, protocell models, metabolism-first approaches, and theories based on organizational closure. None has established a universally accepted description of the first living system, and the last universal common ancestor (LUCA) should not be identified with the first life. This paper asks a different question from within the Self-Preserving Flow (SPF) framework: «What would have to exist before biological life could possess a persistent lineage?» SPF proposes that persistence is not fundamentally determined by preservation of a material substrate. Instead, persistence requires the preservation of historically recoverable organizational continuity through transformation. Within this perspective, the Semantic Consistency Layer (SCL) is not identified with a particular molecule such as DNA or RNA. Rather, this paper proposes the concept of Proto-SCL (SCLproto): the minimal continuity core of a prebiotic organization whose preservation is necessary for its lineage to remain historically recoverable under admissible transformation. The paper develops this proposal in five stages. First, it distinguishes organizational closure from lineage continuity. Second, it defines Proto-SCL as a potentially smaller subset of the constraints constituting an organizationally closed system. Third, it introduces a representation-robust criterion for lineage relevance, avoiding dependence on a single arbitrary state-vector representation. Fourth, it defines a counterfactual continuity test and a Continuity Robustness Envelope (CRE). Finally, it converts the theory into an executable experimental protocol through a preregistered threshold and analysis procedure and an operational toy model for testing the proposed Emergent Identity Criterion of SPF (EIC-SPF).