Mam Voice System Profile (theory-neutral)

Theory-neutral typological profile of the Mam voice system.

The Minimalist VoiceHead, ClauseSpine, and MamDirHead apparatus that previously lived in this file (=(y)a' analysis, antipassive) moved to:

• Phenomena/FillerGap/Studies/ElkinsTorrenceBrown2026.lean — primary anchor for the Minimalist treatment of =(y)a' / oblique extraction (@cite{elkins-torrence-brown-2026}); also houses the antipassive Voice apparatus from @cite{scott-2023} §2.5.4.1.
• Cross-Studies consumer: Phenomena/Agreement/Studies/Scott2023.lean imports the Minimalist Mam Voice from ETB2026 to compare φ-Agree and oblique-Agree pipelines.

This Fragment file retains only mamVoiceSystem : VoiceSystemProfile — a theory-neutral typology profile any framework can consume.

Variety note: SJO Mam (San Juan Ostuncalco, @cite{elkins-torrence-brown-2026}) and SJA Mam (San Juan Atitán, @cite{scott-2023}) are distinct varieties. The voice system profile abstracts over the variety distinction.

def Fragments.Mayan.Mam.mamVoiceSystem : Interfaces.VoiceSystemProfile

Mam voice system: three-way asymmetrical (agentive / passive / antipassive).

Unlike Toba Batak's symmetrical pivot system, Mam's agentive voice is the basic form (phase head, overt agent) and passive/antipassive are derived (non-phase, implicit agent). Voice does not determine pivot for extraction — instead, Voice carries [uOblique] which conditions extraction morphology (=(y)a').

Equations

• One or more equations did not get rendered due to their size.

theorem Fragments.Mayan.Mam.mam_voice_system_asymmetrical : mamVoiceSystem.symmetry = Interfaces.VoiceSystemSymmetry.asymmetrical

theorem Fragments.Mayan.Mam.mam_voice_count : mamVoiceSystem.voiceCount = 3

theorem Fragments.Mayan.Mam.mam_not_simple_active_passive : ¬mamVoiceSystem.isActivePassive

Mam is not a simple active/passive system — it also has antipassive.

theorem Fragments.Mayan.Mam.mam_no_oblique_pivots : ¬mamVoiceSystem.distinguishesObliques