Seventh Concordance’s Annex on Dimensional Taxonomy

The Seventh Concordance's Annex on Dimensional Taxonomy is the sixth annex to the Seventh Concordance, ratified in Year 47 of the Seventh Librarianate, and is the instrument by which the Tower first undertook to describe subjects that had not yet been found. Its opening clause states the difficulty plainly: a taxonomy of non-existent subjects must proceed without specimens, and must therefore classify not things but the terms on which things might later be admitted. Clause 33 of the Annex formally instituted the practice of Provisional Numbering, under which a chamber may be numbered before it has been measured, named, or located. The practice has since spread to every floor of the Tower above the ninetieth, and to several below it that dispute the count.

Structure and the provisional method

The Annex is organised in thirty-nine clauses, of which the first eleven concern definitions, the next twenty the mechanics of provisional structures, and the remainder the settlement of discrepancies arising from the first two parts. Its central device is what the drafters called the provisional structure: a holding may be entered in the register at half weight — that is, recorded but not counted — for a period not exceeding four Librarianates, pending confirmation by a Librarian-Taxonomist acting under the Ordinance of Dimensional Taxonomy.

Clause 33 sets out the numbering itself:

"Where a chamber is emergent — that is, where its dimensions are attested by fewer than three surveyors of the Directorate of Dimensional Fidelity — it shall receive a number drawn from the reserve, and that number shall be marked provisional by the addition of the letter P, in red, at the foot of the door, at a height of one hand and four fingers from the threshold."

— Seventh Concordance's Annex on Dimensional Taxonomy, Clause 33

The red letter is the only compulsory decoration in the Tower. A maintenance note appended by the Temporary Maintenance Clause permits it to be omitted where a door is under repair, provided the number is spoken aloud by the surveyor on each entry and the omission is recorded in the floor ledger.

Application on the One Hundred and Fifth Floor

The first systematic use of the Annex was on the One Hundred and Fifth Floor, whose chambers were numbered in a single session in the winter of Year 49 by a panel of nine surveyors under the presidency of Librarian-Taxonomist Oris Vane. The numbering of chambers on the One Hundred and Fifth Floor follows the Annex to this day, including its faults. Chamber 105-P-14, for instance, is not on the floor; its door was measured, numbered, and entered in the ledger, but the surveyors could not agree on which side of the corridor it opened from, and the question was referred to the Curators of the Grand Taxonomy, who have not returned it.

Vane's panel also produced the so-called Fifth Schedule, a table reconciling the Annex's provisional numbers with the older numbering retained by the floor's original custodians. The Fifth Schedule has never been printed in full; a fair copy is said to be held in the annexe of the Parallax Halls, though the Seventh Concordance dimensional schema governs research within the Parallax Halls and no reader has been granted access to the table since Year 71.

Discrepancies and the Floor 33 question

The Annex's reputation for precision has not survived its own schedule. Annex Ω to the Seventh Concordance documents a discrepancy in dimensional measurements on Floor 33 that is generally traced to the Annex on Dimensional Taxonomy's failure to distinguish between a chamber measured along its walls and a chamber measured along its shelving. The two methods differ by between nine and fourteen feet on that floor. The Directorate has declined to say which method the Annex intended, on the grounds that clause 14(b) of the parent Concordance classifies non-binding dimensional drift as a procedural nullity, and that a decision either way would convert a nullity into a finding.

Scholars of the Standardized Volumetrics school argue that the Annex's silence was deliberate — that clause 33 was drafted to number chambers, not to measure them, and that the Floor 33 discrepancy is a category error committed by later surveyors who mistook a numbering instrument for a measuring one. The opposing view, advanced most fully by the Annex of Litigious Outcomes, holds that a number implies a dimension, since a chamber numbered 40 must be smaller than a chamber numbered 400, and that the Annex therefore legislated measurement without saying so. Neither party has attempted to explain what a chamber numbered 105-P-14 is smaller than.

Relation to later instruments

The Annex has been amended four times, twice to correct its own cross-references and twice for reasons unstated. Its dimensional standards for confined holdings were superseded by Seventh Concordance, Annex 4 and, in respect of display niches, by the protocols of the Forty-Seventh Concordance, though the older clause remains in force wherever a niche predates Year 60. The Seventh Concordance, Annex Theta extends the Annex's provisional method to portable holdings, with the consequence that a casket may now be numbered before it is filled.

Procedural authority for the Provisional Grade certification is derived directly from the Annex, and the certification's seal bears its clause number. A seal struck with the wrong numeral — as happened throughout Year 76, when the scriptorium used a worn die and produced seals reading 35 — was ruled void by the Seventh Concordance, Annex Q in a decision upheld, after appeal, under Seventh Concordance, Annex Q, Paragraph 12. Holders of the year's seals were not recompensed. The Annex D on Ventilation and Circulation is occasionally confused with the Annex on Dimensional Taxonomy by readers consulting the wrong end of the volume; the Directorates maintain separate reading rooms for each, and the rooms are on different flights.

Textual history

The Annex survives in three recensions. The received text is the Third Recension, printed in Year 58 and reprinted with corrections in Year 63; the corrections are not marked. The First Recension, known from a single partial copy in the Delta bundle, lacks clause 33 entirely and numbers its clauses from 12 onwards, which suggests that the institution of Provisional Numbering was added to an earlier draft rather than conceived with it. The Second Recension has not been seen since Year 51 and is cited confidently in at least nine later documents.

A query raised by the Clause 22 committee as to whether the Annex binds floors numbered provisionally under its own Clause 33 remains open. The committee's minute of Year 64 records only that the question was put, seconded, and adjourned, and that the room was needed for something else.