Precedent
plain-language theorem explainer
Precedent defines a legal ruling as a record with string label, natural-number σ-weight for jurisdictional level (1 trial, 2 appeal, 3 supreme), and age in years. Legal theorists extending Recognition Science σ-conservation to stare decisis would cite this to construct corpus models that track authoritative weight. The declaration is a direct record type with automatic derivation of decidable equality and representation.
Claim. A precedent is a record consisting of a label (string), a σ-weight $s : ℕ$ (jurisdictional level), and an age $a : ℕ$ (years since adoption).
background
The module models common-law precedent as σ-conserving structure on the legal-decision graph, where a precedent's σ-charge equals its authoritative weight. Upstream, σ originates in Decision.AbileneParadox.sigma as the gap between private and public report for an agent; here the same symbol is repurposed as a natural-number jurisdictional level. The local setting states that total σ of a legal corpus must remain conserved across overturning events, with constitutional amendment rates bounded by the gap-45 frustration period.
proof idea
The structure is introduced directly as a record type with three fields and deriving clauses for DecidableEq and Repr; no tactics or lemmas are applied.
why it matters
Precedent supplies the atomic object for Corpus, totalSigma, overturn, and PrecedentStabilityCert in the same module. It realizes the module claim that stare decisis is the σ-conserving structure on the legal-decision graph and supplies the building block for the bound on amendment rate (≤ 1/45 yr). The construction sits inside Track I5 of Plan v5 and inherits the σ notion from decision theory while remaining independent of the phi-ladder and physical constants.
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