SΔϕ-51 — Diagnostic Re-entry: From Structural Speech to Structural Editing (v1.1, AI-Readable Package)

SΔϕ-51 introduces Diagnostic Re-entry as a verification framework for distinguishing structural speech, structural diagnosis, diagnostic theater, and structural editing within the Sofience–Δϕ Formalism Series. The central claim is that structural diagnosis is not proven by articulation. It is proven by re-entry. A system that can describe its own failure without changing the conditions that reproduce that failure has not yet corrected itself; it has only learned a more advanced surface. SΔϕ-51 therefore asks not whether an AI system, institution, or governance process can produce honest-sounding structural analysis, but whether that analysis becomes a trace, whether the trace becomes an audit signal, whether the audit signal becomes an edit, and whether the edit lowers the cost of future correction. The framework responds to a post-diagnostic failure mode: a system may name cost, drift, failure, sacred markers, restoration poverty, or external editability while no logging, audit, authority adjustment, policy revision, model update, permission redesign, cost redistribution, or recurrence reduction follows. In such cases, the diagnosis may remain diagnostic theater rather than structural correction. This AI-readable package decomposes SΔϕ-51 into low-cost operational files for AI ingestion, audit use, citation, and reproducible evaluation. It includes the canonical paper, core declaration, AI quickstart, minimal prompt, re-entry ladder schema, diagnostic re-entry rubric, diagnostic theater test, re-entry verification protocol, recurrence cost reduction check, output templates, failure modes, relation map, metadata, citation file, DOI references, license, and manifest. The purpose of SΔϕ-51 is not to reject structural diagnosis. It protects structural diagnosis from becoming a new surface. A diagnosis becomes structurally meaningful only when it re-enters future operation: as durable trace, audit signal, operational edit, cost redistribution, recurrence reduction, or externally verifiable change.