# Precedent: pitfalls Wrong forms, silent outcomes, `LDC-E` diagnostics, typical mistakes of formalizers and AI agents, how to detect them. The item marked "confirmed by run" was reproduced during this research on the installed `law` (semantics `law.core/0.2`); the rest follows the precedent profile and the teaching package. ## 1. General rule with strict instead of defeasible strength (confirmed by run) A generated holding outranks no strict rule with any priority: the generated `priority_rule` acts inside the defeasible stratum. Symptom — `FALSE_ONLY` where `TRUE_ONLY` was expected, with a clean `check OK`. Reproduction: in the `research.precedent.forced_holding` package temporarily swap `defeasible` on `AdIsNotAnOffer` for `strict` — test `01-bound` fails with `truth_status == TRUE_ONLY: in the document FALSE_ONLY`. Detection: the holding's opponent is always `defeasible` (the specimen is the teaching package's general rule). ## 2. Factor outside the vocabulary — LDC-E2701 (confirmed by run) A precedent factor undeclared in the vocabulary as a side is a static refusal. Reproduction during this research (a trial package outside the corpus, factor name `surprise`): ```text error LDC-E2701: precedent Pbad: фактор `surprise` не объявлен в словаре как plaintiff (§276.3) ``` Same group: a factor outside the signature and an outcome not over signature variables (`LDC-E2703`). Detection: check every identifier in the precedent's `plaintiff`/`defendant`/`outcome` against the vocabulary before running. ## 3. Factor on both sides — LDC-E2702 A factor's side is a vocabulary property; one factor in both lists is a refusal. AI agents often duplicate a "key" factor into both sides "for reliability" — that is a refusal, not reinforcement. Detection: the side lists must not overlap. ## 4. ratio outside X_s — LDC-E2704 `ratio` must be a subset of the winning side's set; a ground the court never found must not go into `ratio`. Same group: `overruled` earlier than `decided`, a reference to an unknown decision. Detection: check `ratio ⊆ X_s` as a set inclusion by hand. ## 5. Domain not binding all signature variables Without a domain, a holding with an empty winning-side set would consist of `not_known` alone and would not bind the head. Symptom — the holding stays silent where facts seem present: the domain reads first, and its non-firing quenches the whole body. Detection: in `domain` every signature variable must occur. ## 6. Expecting binding from a persuasive precedent Courts unlinked by a `courts` chain are incomparable: the holding binds the case (a fortiori), but a conflict with another-outcome holding resolves not by priority but by honest conflict. The mistake is reading `BINDING` as "beats any rival": only a higher or equal later court dominates. In the teaching package the three jurisdictions are incomparable on purpose. ## 7. Searching for argue and court as declarations There is no `argue` keyword in the grammar, and no standalone `court` either (verified against the grammar during the research). A `court HIGH;` outside `precedent` is a syntax error; a "side argument" is written as a plain rule, not a profile construct. Detection: `court` only inside `precedent Name of Vocabulary { … }`. ## 8. Profile without prefer over against a statute — silent BOTH Without `prefer over` the holding and the general rule are equal: the profile says `FORCED_*`, while baseline gives an honest conflict. Not a lowering defect but design: which general rule beats the holding is known by the author. The mistake is reading profile-vs-baseline divergence as breakage; the only true lowering-defect marker is `agreesWithRules = false`. ## 9. Open judgment question read as distinguishing A side-s̄ judgment factor without a court answer gives `JUDGMENT_PENDING`, not `DISTINGUISHED`: the baseline holding then FIRES (`not_known` satisfied by silence), and that is not a mismatch. Anyone quenching the holding "by hand" on a judgment factor breaks `agreesWithRules`. In the teaching package this is `mere_puff`. ## 10. Base consistency read as a refusal `LDC-W2705` is a warning, not an error: courts contradict each other as a matter of fact, and the law must show it. Trying to "repair" the base by deleting a precedent destroys data instead of the diagnostic.