Normative Curator Instruction — A : B Comparison and Validation Gate

Purpose

This instruction defines a **mandatory curator-controlled validation step** that MUST be executed before a *provisional* Corpus Map (B) is accepted as a canonical upgrade over an existing Corpus Map (A).

This gate exists to prevent silent drift, inference creep, or accidental re-authoring of corpus structure.

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Preconditions

The curator MUST have:

A currently authoritative Corpus Map document (A)
A candidate replacement Corpus Map marked provisional (B)
Both documents available side-by-side for inspection
Identical canonical dimension tables declared in both documents

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Required Curator Actions (Normative)

Step 1 — A : B Structural Comparison

The curator SHALL perform an explicit before/after comparison between A and B, verifying that:

No artefacts have been added or removed unintentionally
No artefact titles have been normalised, paraphrased, or retyped
No artefacts have changed publication dates
No dimensions have been renamed, merged, split, or reordered
No new dimensions have been introduced beyond the declared canonical set

Any deviation MUST be treated as a rejection condition unless explicitly intended and documented.

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Step 2 — Projection Completeness Validation

The curator SHALL validate that B:

Preserves all projections present in A
Corrects omissions rather than introducing reinterpretation
Projects only dimensions already declared in the canonical dimension table
Includes all eligible artefacts in both:

 * the Time-Ordered Projection, and
 * the Dimension-Centric Projection

B MUST NOT reduce coverage relative to A.

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Step 3 — Inference Boundary Check

The curator SHALL confirm that B:

Does not expand the inference space
Does not assign dimensions based on stylistic or topical proximity alone
Does not introduce evaluative or interpretive structure beyond projection rules

Projection density MAY increase; inference scope MUST NOT.

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Step 4 — Acceptance Decision

If (and only if) Steps 1–3 are satisfied, the curator MAY accept B as a valid upgrade.

Acceptance SHALL be signalled by all of the following actions:

Removal of the “provisional” designation from B
Increment of the document version number
Addition of a dated update note in the metadata table describing the change
Replacement of A with B as the authoritative Corpus Map

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Postconditions

Upon acceptance:

B becomes the canonical Corpus Map
A remains valid as a historical artefact unless explicitly retired
No downstream corpus artefact is retroactively reinterpreted

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Governance Principle

This procedure enforces the rule that:

> **Corpus Maps may be regenerated, but never silently replaced.**

Human review, comparison, and explicit acceptance are required for all structural upgrades.