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:

• Studies/ElkinsTorrenceBrown2026.lean — primary anchor for the Minimalist treatment of =(y)a' / oblique extraction ([ETB26]); also houses the antipassive Voice apparatus from [Sco23] §2.5.4.1.
• Cross-Studies consumer: Studies/Scott2023.lean imports the Minimalist Mam Voice from ETB2026 to compare φ-Agree and oblique-Agree pipelines.

This Fragment file retains only VoiceSystem.voices / VoiceSystem.symmetry — a theory-neutral voice inventory any framework can consume via the Voice.* queries.

Variety note: SJO Mam (San Juan Ostuncalco, [ETB26]) and SJA Mam (San Juan Atitán, [Sco23]) are distinct varieties. The voice system profile abstracts over the variety distinction.

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').

Agentive is basic (phase head); passive/antipassive are derived. Antipassive demotes object to oblique, subject gets ABS ([Sco23]). Voice data from SJA ([Sco23]) and SJO ([ETB26]).

def Mam.VoiceSystem.voices : List Voice.VoiceEntry

The voices of Mam: agentive (basic), passive, antipassive.

Equations

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

def Mam.VoiceSystem.symmetry : Voice.VoiceSystemSymmetry

Mam is asymmetrical — agentive is the basic voice.

Equations

• Mam.VoiceSystem.symmetry = Voice.VoiceSystemSymmetry.asymmetrical

theorem Mam.mam_voice_system_asymmetrical : VoiceSystem.symmetry = Voice.VoiceSystemSymmetry.asymmetrical

theorem Mam.mam_voice_count : Voice.voiceCount VoiceSystem.voices = 3

theorem Mam.mam_not_simple_active_passive : ¬Voice.isActivePassive VoiceSystem.voices

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

theorem Mam.mam_no_oblique_pivots : ¬Voice.distinguishesObliques VoiceSystem.voices