Terminological Lexicons

Terminological Lexicons are the sanctioned word-lists by which the Tower fixes the meaning of terms within a given floor, chamber, or instrument, and by which it distinguishes one such term from every other term it resembles. They are not dictionaries. A dictionary records what a word has been taken to mean; a Terminological Lexicon stipulates what a word shall mean for the duration of a proceeding, and provides, in its rear leaves, the schedule by which that stipulation may be withdrawn. The distinction is maintained by the Nomenclature Board and was, until the Seventy-Seventh Clarification, maintained instead by the Nomenclature Guild under a scheme that no surviving recension describes in full.

Form and custody

A Lexicon is issued in three parts. The Head lists the controlled terms in the order of their first citation across the Tower's instruments, which is to say in no useful order. The Body gives each term a stipulated sense, a list of forbidden near-synonyms, and a note of any Annex in which the term has previously been used with a different sense. The Tail contains the revision schedule and the seal of the issuing body. Lexicons are held in the scriptoria of the floors to which they apply and, in one copy each, in the chamber of the Librarians responsible for that floor. Copies are not lent. A clerk requiring a Lexicon consults it in the scriptorium, in the presence of the scriptorium's own clerk, and may take away only a written paraphrase, which is itself a Terminological Lexicon of limited scope and must be sealed as such.

Binding is by quire, never by case. A Lexicon found bound as a single volume is presumed to be a forgery or a Pre-Concordant Vernacular compilation, and either way is not to be corrected by the reader.

The Literalist dispute

The central controversy of the Lexicons concerns the degree to which a stipulated sense travels. The Doctrine of Terminological Fixity, advanced by the Strict Constructionists, holds that a term defined in one Annex carries no meaning whatever in another unless expressly cross-referenced, so that the word chamber in Annex C-4 of the Third Concordance and the word chamber in the Sixth Concordance denote two unrelated objects that have agreed to be spelled alike. The Latitudinarian party, whose position survives chiefly in the marginalia of scriptorium copies, holds instead that a controlled term, once sealed, travels with its sense wherever it is carried, and that the cross-reference is a courtesy rather than a condition.

The practical consequences diverge sharply. Under Fixity, a Lexicon of 340 terms may require as many as 900 entries once the senses are distributed across the Annexes in which the terms actually appear. Under Latitudinarian reading the same Lexicon requires 340, and the difference is generally borne by the junior clerk who must copy it out. The dispute was partly narrowed by Declaration 88-C, which prohibited recourse to the Inquest mechanism for purely terminological matters absent demonstrative ontological consequence. The wording left open what a demonstrative ontological consequence might be, and the question has since occupied two full sessions of the Nomenclature Oversight Conclave.

Incident 902-Ξ

The most cited case in the Lexicon literature is Incident 902-Ξ, in which a consignment of self-referential lexicons dispatched from Floor 714 was received in Chamber Delta without the customary quarantine of the Tail. The lexicons defined their own controlled terms by reference to themselves, a construction permitted in the Head but forbidden in the Body, and the omission was not detected at intake. A Validator and a Recorder working the consignment entered a perceptual loop that lasted, by the Recorder's later account, "four days, or the same afternoon, the record does not agree with itself" (Recorder's Deposition 902-Ξ/7). Both were recovered. The Validator declined to certify any subsequent shipment from Floor 714 and was reassigned to the Partial Survey. The quarantine of Tails was made mandatory thereafter and is enforced by the scriptorium clerk, who need not read the Body to do so.

Lexicons and other instruments

Terminological Lexicons are frequently confused with Shadow Catalogues, which also list terms but list them for the purpose of identifying non-standard photic phenomena, and which are procedural manuals first and word-lists second. The Accord on the Standardization of Hypothetical Lumens depends on both and reconciles them only by an expedient: a Lexicon term that names a phenomenon already catalogued in a Shadow Catalogue is entered in the Lexicon with its Shadow Catalogue number appended in brackets, and the bracketed number is not itself a controlled term. Disputes over the bracketed numbers are heard by the Silent Divan under the Obsidian Decree, which permits the sign-language lexicons and nothing spoken. The Ambiguous Calipers are not a measuring instrument for the purposes of any Lexicon and are listed in the Head of every Lexicon issued since Cycle 844 solely so that the point is not raised again.

Where a Lexicon is silent, the Standardization schedules govern. Where the schedules are silent, the matter is settled by whichever Concordance was most recently amended, a rule that has produced the Crisis of the Twin Directives and no settled resolution of it.

The 887 recension and the missing term

The recension of Cycle 887, prepared under the direction of Clerk Overseer Halvene Marrow, reduced the master Lexicon from 1,204 entries to 1,197 by the consolidation of seven terms held to be duplicates. Six of the seven were uncontested. The seventh, a term denoting the space between two adjacent stair landings, was consolidated into a term denoting a landing itself, on the ground that the space between landings had never been separately furnished and could not therefore be separately meant. Marrow defended the consolidation in a memorandum of nine leaves, of which the ninth is missing from every known copy.

"The distinction was maintained for four hundred cycles and no instrument has ever required it. I do not say the space is nothing. I say the Lexicon does not need to say it."

— Marrow, Memorandum on the 887 Recension, leaf 8

The consolidation was reversed in Cycle 903, not on the merits but because the Reabsorption Protocols of the Office of Taxonomical Purgation had in the interim classified the consolidated entry as having achieved terminological critical mass, and the Office would not de-accession an entry that had already been merged. The term was restored as a new entry with a new number and the note "restored; formerly itself." Marrow's ninth leaf has not been located. Clerks consulting the 887 recension are asked to report any copy in which it survives, and to leave the Lexicon open at the Tail until the scriptorium clerk has seen it.