Interlocutor Matrix

The Interlocutor Matrix is the collective designation for two distinct instruments of the same name held in separate custodial offices of the Tower: the first used by the clerks of the Bureau of Implementable Abstraction to model the logical consistency of proposed antecedent relationships, and the second a classified instrument of the Dialogists, employed to model possible antecedent questions or challenges against which a given clause may be tested for coherence as a reply. The two instruments are not interchangeable, are not derived from one another, and have never been compared side by side by any clerk authorised to do so. Concordance 41 nevertheless treats them as a single article and assigns both to the Bureau of Implementable Abstraction.

Origin and custody

The Matrix was established by Ordinance 811-C in the year the Tower's records number as 3,104, in the aftermath of the Second Recension, when the Bureau found itself unable to distinguish a clause that answered an unstated question from a clause that answered nothing at all. The early device was a wooden frame of eleven slats, each bearing a named category of antecedent and a facing category of reply, scored down the middle so that the pairs could be slid past one another. Clerks recorded confirmations and refusals on a tally sheet. The tally sheets for the first forty years survive in the Annex of Minor Instruments and are occasionally consulted for the light they throw on early usage; they are no longer considered evidentiary and are kept chiefly because the Annex has never been granted authority to discard anything.

The Matrix is currently held in a locked cabinet on the third landing of the Bureau's west stair, opened on the verbal instruction of the Keeper of the Slats and not otherwise. Ruling 4491 exempts it from the general obligation to be entered in the Adjacency Matrix, on the grounds that the Matrix is a tool and not a thoroughfare. The exemption has been challenged twice and upheld twice, on the second occasion after the Keeper observed to the Order of Arbiters that nobody had ever asked to travel through the Matrix and the question was therefore idle.

Method and attestation

A clerk using the Matrix proposes an antecedent and a clause and works the slats until the pairing produces one of four results: supported, unsupported, inconclusive, and — the fourth, added by Ordinance 1022-G, which is already recorded elsewhere in this archive — antecedently void, meaning that the clause is a perfectly good reply and the question to which it replies could not have been asked. A result of antecedently void is not a fault in the clause. It is a fault in the questioner, and the Bureau's practice is to return the question with a note.

Because the Matrix produces a finding rather than a document, it must be attested before it can be cited. Attestation is by a second clerk, who reads the result aloud and confirms it in the general ledger; a finding of inconclusive requires the attendance of the Deputy Registrar for Abstraction and is normally allowed to stand. The Matrix was attested fourteen times in the winter of the fourth survey, twelve of them on the same afternoon, on a matter concerning the Antecedent Forms of the Lower Shelving that was never resolved and is listed in the catalogue as still open.

The Dialogists' instrument is described in their own Dialogist Handbook, 9th fascicle as "a tool for asking what had to be true outside the clause for the clause to be its own answer" — a phrasing the Bureau has formally objected to twice without proposing an alternative. It is smaller, lozenge-shaped, and kept in the Dialogists' room, to which the Bureau has no right of entry.

Dispute with the Bureau of Implementable Abstraction

The standing friction between the two offices dates from the year's records number 4,217, when a Dialogist of the third form, Severin Ost — later known within the Dialogists chiefly for a reputation for asking unanswerable questions at table — submitted a finding to the Bureau that had been produced on the Dialogists' Matrix and was therefore not attestable by the Bureau's method. The Bureau refused it. The Dialogists returned it. The Bureau refused it again, this time in writing and at greater length.

The dispute was arbitrated in the following spring and turned on the question of what, precisely, the Matrix attests. The Bureau held that the Matrix attests a relation between a question and a clause. The Dialogists held that it attests the possibility of a question, which is prior to any relation and cannot therefore be attested by an instrument of the same order. The Arbitration of the Two Matrices found for the Bureau on the ground of custody and for the Dialogists on the ground of description, which is to say that it decided nothing and was regarded by all parties as even-handed.

"The instrument before us establishes that a question may exist; it does not, and cannot, establish that it has been asked. The distinction is not pedantic. It is the distinction on which the whole of the third landing depends."

— Arbitration of the Two Matrices, finding 4

Since the Arbitration the Bureau has declined to reconsider Dialogist findings and the Dialogists have declined to submit them. A proposal by the Office of Concordance Review in the records numbered 4,380 that the two instruments be compared in a single sitting has been carried forward in the docket for eighty-one years. It has been renewed eleven times and read once.

Known limitations

The Matrix cannot test a question against itself. Attempts to do so — proposed in the year's records number 4,070 by a clerk of the fourth form, whose name appears in the ledger only as "Verity, on loan from Shelving" — produce a finding of unsupported regardless of the question, which the Matrix's own guidance describes as "a feature of the instrument and not a verdict upon the asker." Verity's report to the Keeper, that the instrument had given the same answer thirteen times running and was therefore "either broken or right," was filed without comment.

It also cannot be used while wet, and the cabinet is not to be opened on the damp days of the third quarter of the year.

Status

The Matrix remains in use. The Bureau's copy is inspected annually by the Keeper of the Slats and oiled; the Dialogists' copy is inspected by no one, a state of affairs the Bureau has noted in three separate memorials and the Dialogists have not seen fit to answer. Both are cited regularly in the resolution of antecedent disputes, and it is not unknown for a single dispute to be decided on both instruments in turn, arriving at the same finding by incompatible means, which is generally considered the strongest result the Tower affords.