Taxonomy Amp Cataloguing

Taxonomy Amp Cataloguing (TAC) is the disciplined assignment of an object, condition, or floor to its correct position within an established taxonomy by means of an amplifier-assisted reconciliation procedure, conducted under the standing taxonomic conventions of the Tower and audited against the STNEM and qualia-weight registers where the subject falls within their respective fields. It is not itself a taxonomy. TAC is a method of arriving at one, and the distinction has been the cause of nearly every dispute in the field since the practice was first regularised in the year 3,041.

The method arose from a practical impossibility. An object recovered from an unsurveyed floor may be catalogued only if a classification exists for it; a classification may be established only after the object has been catalogued. TAC interrupts this loop by treating the object's taxonomic neighbour as the instrument of measurement. A Cataloguing Amp of Type-VII-C is set to its pre-calibrated isolation mode and directed at the nearest recorded holding, not at the subject under examination; the resulting differential — the "taxonomic gap," expressed in decimals of position — is then recorded as the subject's provisional placement pending full concordance.

Procedure and the Amplifier's Function

In a standard TAC session the operator establishes a low-grade stasis field, as in Isolation Amp Cataloguing, and then takes three readings: an anchor reading on a known holding, a null reading on the empty floor, and the gap reading on the subject. The three together fix the subject in classification space with an accuracy that the Bureau of Registry has repeatedly affirmed to be sufficient, though the Bureau has never specified sufficient for what. The operator does not judge the subject's nature. Judgment is expressly prohibited under the TAC clauses of Forms Amp Petitions, on the ground that a clerk who has already formed an opinion cannot be trusted to measure it.

Objects that resist placement are held in the Buffer at Floor 8,002 pending classification. A Buffer item is not a subject. A Buffer item is a subject-shaped absence of classification, and may not be photographed.

The Dispute of the Fourth Recension

Scholarship divides on whether TAC produces a taxonomy or merely discovers one. The dispute is old and has hardened into two schools. The Placement School holds that the act of measuring position creates the classification: nothing is anywhere until it is measured to be there, and it is therefore nonsense to speak of a misplaced object, only of an object placed by a different clerk. The Discovery School holds that every object has a true position that the amplifier discloses, and that error consists in reading it wrongly.

"The instrument discloses what was always so; it does not confer. A subject out of its correct position is a subject the catalogue has failed to see, not a subject the catalogue has invented."

— Third Concordance, Annex 4, marginal gloss

The opposing view is recorded in the Fifth Concordance without rebuttal of the above, the Fifth having been amended in 3,104 in a manner that removed the section to which the rebuttal was attached. No one has been able to establish which is the governing text. Practitioners proceed as if the Placement School were authoritative and file their returns as if the Discovery School were, a compromise that the Department of Ambiance Amp Inclemency has declined to disturb.

The Grievance of Clerk Vandis

The most-cited incident in the field is that of Clerk Anselm Vandis, assigned to a TAC audit of a consignment of unspecified minerals recovered from the aperture transitions during the winter of 3,197. Vandis measured the consignment against the nearest recorded neighbour and, finding the gap reading of 0.000 — a perfect overlap — placed the minerals in their neighbour's classification without further step. The neighbour was a class consisting entirely of itself. The consignment and the neighbour became the same object, both recorded, neither described, and the resulting petition occupied the Registry for eleven years before it was dismissed as being about nothing that could be ruled upon.

Vandis's grievance is preserved in the Registry files and is not concerned with the minerals. It concerns the fact that his finding of a zero gap was correct, and that no subsequent procedure could be found in the Concordances for a case in which the measurement was correct and the classification had never existed. He requested a ruling on the point. The request was granted, and the ruling was that the point had been correctly reached.

Relation to Ceremonial Practice

TAC must be distinguished from the ceremonial assignment of taxonomy, in which classification is performed as a public act and the correctness of the result is not at issue. The Ceremonial Cataloguing Amp is reserved for that purpose, and the Class Delta ceremonial recensions govern its use. A common error, and one that has generated litigation on at least four floors, is the use of a ceremonial instrument for a TAC measurement; the ceremonial amp returns a position in the ceremonial order, which is not a taxonomic order and does not answer the question put to it. The resulting classification is valid and cannot be undone, but it is in the wrong register.

The Bureau of Registry adjudicates these disputes under the demarcation instruments of Title VII. Operators are cautioned to confirm the instrument's designation before the session begins. A ceremonial amp will not accept the isolation mode, and any operator who sets the mode selector by feel rather than by reading the plate does so at their own cost.

Current Standing

TAC remains the standard method for the initial classification of undocumented holdings. RMRCP-III incorporated TAC into its Formalization Amp Codification, and Isolation Amp Cataloguing has adopted TAC's gap reading as its required opening measurement. The practice is therefore in use at every level where holdings are first received, from the receiving floors to the unnumbered stairheads where nothing has yet been measured and everything is, in principle, a subject.