Auditory Phantasma Taxonomy

The Auditory Phantasma Taxonomy (APT) is the primary classificatory framework governing the organization, authentication, and cross-referencing of all sound-generating phenomena catalogued within the Tower. Maintained by the Spire of Auditory Phantoms, the APT provides a procedural and ontological structure for distinguishing between canonical auditory events and unverified Auditory Residue. Its authority is derived from, and is frequently reconciled with, the broader Grand Taxonomy, particularly following the protocols established during the Great Re-cataloguing.

Structural Principles

The APT operates on a tripartite foundation: Source, Manifestation, and Confirmation. The Source axis categorizes the point of origin (e.g., spontaneous, induced, or residual). The Manifestation axis describes the acoustic character, such as harmonic, dissonant, or silent-phase. The Confirmation axis records the procedural status, ranging from "unverified" to "canonically affirmed" following an Auditory Confirmation hearing.

A core tenet, as outlined in Annex Delta of the Grand Ledger of Auditory Potential, is that a sound does not achieve ontological stability within the Tower's records until it has been processed through the APT and assigned a unique alphanumeric identifier (e.g., APT-413-γ-7). This process transforms ephemeral phenomena into archival objects.

Administrative Implementation

Day-to-day administration of the APT is decentralized across several bureaus. The Auditory Permit Office handles initial classification and issuance of permits for intentional sound-generation studies. The Curators of the Grand Taxonomy are responsible for the annual reconciliation of the APT with other taxonomic systems, such as the Imperial Taxonomy and the Great Taxonomy of Implied Fauna. Floor-specific adaptations are common; for instance, the cataloguing system on Floor 413 is a localized variant of the APT, tailored for the unique phonic properties of that level.

Controversies and Scholarly Disputes

The most persistent debate concerns the taxonomy's scope. A faction within the Spire, often called the "Expansionists," argues that the APT should encompass all vibrational phenomena, including the resonant frequencies of non-catalogued materials and the sub-audible hum of the Tower's own infrastructure. The opposing "Purists," citing Concordance 47, maintain that only discrete, reportable auditory events that undergo Auditory Confirmation are valid subjects. This dispute directly impacts resource allocation for expeditions and the design of instrumentation like the Auditory Resonance Drill.

A further point of contention involves the classification of sounds produced by catalogued entities whose existence is itself predicated on sound, such as the Lysander Beetle's bioluminescent click, which is dependent on its consumption of the Ghost-cap mushroom. Is the sound a property of the beetle, or a separate phantasma to be filed under "biologically-mediated harmonics"? The current APT lists it as a cross-referenced subsidiary entry, a solution satisfying neither school of thought.

Procedural Integration

The APT is fully integrated into broader Tower governance. Any Receiver submitting a report of an anomalous sound must use APT forms (Series 47-B). Furthermore, the vellum for official Concordance Documents, sourced from the Phantom Sheep, is treated with a solution that resonates at a frequency registered in the APT as "Canonical Ground Tone Alpha," thereby embedding an auditory watermark of authority into the physical legislation.

During an Auditory Phase, the APT's protocols become the supreme procedural framework, temporarily superseding even the Administrative Taxonomy for matters pertaining to acoustic inventory. This periodic elevation underscores the Tower's foundational principle that the act of cataloguing is, in itself, a generative and constitutive force.

Related Taxonomies

While supreme in its domain, the APT maintains formal relationships with other classificatory systems. It shares a reciprocal cross-reference schema with the Taxonomy of Unwritten Books, particularly for sounds described within non-existent texts. Its relationship with the Procedural Taxonomy is one of hierarchy, as the APT provides the specific categories through which general procedural rules for evidence-gathering are enacted. This complex web of interrelated systems ensures that a hum, a whisper, or a reverberant boom, once heard and confirmed, finds its precise and immutable place within the Tower's silent, waiting shelves.