FPF Reference

    A.6.B:6 — Cross‑quadrant link discipline

    Preface node heading:a-6-b-6-cross-quadrant-link-discipline:8945

    What this page is

    This is generated FPF reference text from the specification preface or supporting sections. It helps interpret FPF; it is not FPF Reference product documentation.

    Methodology

    Use it to understand how the specification wants to be read, then return to a route, pattern, or work packet for active work. Cite generated IDs only when the wording changes the task decision.

    Content

    The square is not just classification; it is a dependency discipline. Claims often depend on each other; such dependencies MUST be explicit (by claim ID) rather than duplicated prose.

    A.6.B:6.1 — Explicit reference rule

    If a claim’s meaning materially depends on another L/A/D/E-classified claim, that dependency MUST be represented as an explicit reference to the other claim’s ID (or to the canonical location where it lives), rather than by restating it.

    Guideline (informative). Treat this as “import hygiene” for prose: reuse by reference, not by copy.

    A.6.B:6.2 — Canonical cross‑quadrant dependency patterns

    These patterns are valid (and common). The square becomes operational when these links are used systematically.

    (D → A) Duty-to-gate linkage

    When governance requires someone to comply with a gate:

    • D-*: “Role MUST satisfy or enforce A-*.”

    This separates what is admissible (A) from who is responsible (D).

    (E → A) Evidence-for-gate linkage

    When gate decisions must be observable:

    • E-*: “On rejection or acceptance due to A-*, carrier C is produced or observable under conditions …”

    This separates gate semantics (A) from evidence semantics (E).

    (D → E) Duty-to-evidence linkage

    When governance requires evidence production, retention, or exposure or commits to measured properties:

    • D-*: “Role MUST retain or expose carrier class C used by E-* …”
    • D-*: “Provider SHALL meet E-* under exclusions …”

    This separates obligation or commitment (D) from adjudication (E).

    (A/E → L) Semantic grounding linkage

    When a gate predicate or measurement relies on definitions or invariants:

    • A-* / E-* references L-* that define terms or metrics.

    This prevents “metric drift” and “definition drift” across views.

    (D → L) Governance-to-definition linkage

    When an obligation or commitment relies on precise term or metric meanings:

    • D-* references L-* that define the terms or metrics it uses.

    This keeps governance text from accidentally redefining semantics in prose.

    A.6.B:6.3 — The “triangle decomposition” for mixed sentences

    Normative rule (decomposition). A conforming boundary text SHALL decompose any mixed sentence that expresses (i) an entry condition, (ii) an obligation to satisfy or enforce it, and (iii) an observability expectation into the three quadrants:

    • A: admissibility predicate (A-*)
    • D: duty or commitment referencing the gate (D-* → A-*)
    • E: evidence binding referencing the gate (and carriers) (E-* → A-*)

    This is the canonical repair for “contract soup” around validity, authorization, compliance, audit, and security boundaries.

    A.6.B:6.4 — Dependency direction (no “upward” imports)

    The square is intended to preserve layered modularity: semantics should not depend on governance text, and evidence semantics should not depend on duties.

    Normative rule (no upward dependencies).

    • L-* claims MUST NOT depend on or reference A-*, D-*, or E-* claims (except for purely informative notes explicitly marked informative).
    • A-* claims MUST NOT depend on or reference D-* claims. (A-* may reference L-* for defined terms or invariants.)
    • E-* claims MUST NOT depend on or reference D-* claims. (E-* may reference A-* for conditioning and L-* for metric or term meanings.)
    • D-* claims MAY reference L-*, A-*, and E-* claims when needed, and SHOULD do so by ID rather than restating content.

    Rationale (informative). This keeps foundational meaning stable (L), keeps runtime gates independent of governance prose (A), and keeps evidence semantics independent of enforcement policy (E). Governance (D) is the place where “who must do what, using which gates and which evidence” is assembled.

    Last Updated: 2026-06-17 — upstream FPF commit 646b0b9b (github.com/ailev/FPF)