Toba Batak Fragment [Erl18]

Morphosyntactic data for Toba Batak (Austronesian, Sumatra) relevant to the extraction restriction and pivot system.

Toba Batak has predicate-initial word order (derived by predicate fronting) and an extraction restriction: only the "pivot" — the voice-determined, clause-peripheral argument — can undergo Ā-movement.

Voice System

Unlike Philippine-type Austronesian languages (Tagalog, Seediq), Toba Batak does not have a full voice/Case system with multiple voices. Two voice morphemes determine which argument is the pivot (= subject):

• Actor Voice (AV): agent is the pivot
• Object Voice (OV): patient/theme is the pivot

The restriction on extraction follows from nominal licensing: only the pivot (Case-licensed by T's [PROBE:D] in Spec,TP) can undergo Ā-movement; a non-pivot DP fronted to Spec,CP would lack a Case licensor. This is NOT a voice-as-Case system in the Philippine sense; it is a structural consequence of how probing and Case assignment interact with predicate fronting.

inductive TobaBatak.Voice : Type

Toba Batak voice: determines which argument is the pivot.

• av : Voice

  Actor voice: the agent is the pivot (clause-final)

• ov : Voice

  Object voice: the patient/theme is the pivot

@[implicit_reducible]

instance TobaBatak.instReprVoice : Repr Voice

Equations

• TobaBatak.instReprVoice = { reprPrec := TobaBatak.instReprVoice.repr }

def TobaBatak.instReprVoice.repr : Voice → Nat → Std.Format

Equations

• TobaBatak.instReprVoice.repr TobaBatak.Voice.av prec✝ = Repr.addAppParen (Std.Format.nest (if prec✝ ≥ 1024 then 1 else 2) (Std.Format.text "TobaBatak.Voice.av")).group prec✝
• TobaBatak.instReprVoice.repr TobaBatak.Voice.ov prec✝ = Repr.addAppParen (Std.Format.nest (if prec✝ ≥ 1024 then 1 else 2) (Std.Format.text "TobaBatak.Voice.ov")).group prec✝

@[implicit_reducible]

instance TobaBatak.instDecidableEqVoice : DecidableEq Voice

Equations

• TobaBatak.instDecidableEqVoice x✝ y✝ = if h : x✝.ctorIdx = y✝.ctorIdx then isTrue ⋯ else isFalse ⋯

def TobaBatak.Voice.pivotRole : Voice → Extraction.ArgumentRole

Which argument role is the pivot for a given voice?

Equations

• TobaBatak.Voice.av.pivotRole = Extraction.ArgumentRole.agent
• TobaBatak.Voice.ov.pivotRole = Extraction.ArgumentRole.patient

inductive TobaBatak.ExtractionJudgment : Type

Whether extraction of a given argument is grammatical.

• grammatical : ExtractionJudgment
• ungrammatical : ExtractionJudgment

def TobaBatak.instReprExtractionJudgment.repr : ExtractionJudgment → Nat → Std.Format

Equations

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

@[implicit_reducible]

instance TobaBatak.instReprExtractionJudgment : Repr ExtractionJudgment

Equations

• TobaBatak.instReprExtractionJudgment = { reprPrec := TobaBatak.instReprExtractionJudgment.repr }

@[implicit_reducible]

instance TobaBatak.instDecidableEqExtractionJudgment : DecidableEq ExtractionJudgment

Equations

• TobaBatak.instDecidableEqExtractionJudgment x✝ y✝ = if h : x✝.ctorIdx = y✝.ctorIdx then isTrue ⋯ else isFalse ⋯

structure TobaBatak.ExtractionDatum : Type

A Toba Batak extraction datum: voice choice + extracted element + judgment.

• voice : Voice

  Which voice the clause is in

• extracted : Extraction.Extractee

  What is being extracted (DP argument or adjunct)

• judgment : ExtractionJudgment

  Whether the extraction is grammatical

• description : String

  Description

@[implicit_reducible]

instance TobaBatak.instReprExtractionDatum : Repr ExtractionDatum

Equations

• TobaBatak.instReprExtractionDatum = { reprPrec := TobaBatak.instReprExtractionDatum.repr }

def TobaBatak.instReprExtractionDatum.repr : ExtractionDatum → Nat → Std.Format

Equations

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

def TobaBatak.ExtractionDatum.extractsPivot (d : ExtractionDatum) : Bool

Is the extracted element the pivot for the given voice? Adjuncts are never pivots (they don't participate in Case licensing).

Equations

• d.extractsPivot = match d.extracted with | Extraction.Extractee.dpArg role => role == d.voice.pivotRole | Extraction.Extractee.adjunct => false

def TobaBatak.avAgentExtraction : ExtractionDatum

AV + agent extraction: grammatical (agent is pivot in AV).

Equations

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

def TobaBatak.avPatientExtraction : ExtractionDatum

AV + patient extraction: ungrammatical (patient is not pivot in AV).

Equations

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

def TobaBatak.avObliqueExtraction : ExtractionDatum

AV + oblique extraction: ungrammatical (oblique is never pivot).

Equations

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

def TobaBatak.ovPatientExtraction : ExtractionDatum

OV + patient extraction: grammatical (patient is pivot in OV).

Equations

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

def TobaBatak.ovAgentExtraction : ExtractionDatum

OV + agent extraction: ungrammatical (agent is not pivot in OV).

Equations

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

def TobaBatak.ovObliqueExtraction : ExtractionDatum

OV + oblique extraction: ungrammatical (oblique is never pivot).

Equations

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

def TobaBatak.avAdjunctExtraction : ExtractionDatum

AV + adjunct extraction: grammatical (adjuncts don't need Case).

Equations

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

def TobaBatak.ovAdjunctExtraction : ExtractionDatum

OV + adjunct extraction: grammatical (adjuncts don't need Case).

Equations

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

def TobaBatak.extractionData : List ExtractionDatum

All monoclausal extraction data.

Equations

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

def TobaBatak.tbExtractionStrategy : Extraction.ExtractionMarkingStrategy

Toba Batak extraction strategy: structural restriction (pivot-only).

Language: "Toba Batak". Notes: Only the pivot (= surface subject) can be extracted; voice alternation (AV/OV) determines which thematic role occupies the pivot, but the extractable structural position is always subject. Restriction derived from predicate fronting + nominal licensing: non-pivot DPs in Spec,CP lack a Case licensor ([Erl18], §4).

Equations

• TobaBatak.tbExtractionStrategy = Extraction.ExtractionMarkingStrategy.voiceAlternation

def TobaBatak.tbExtractionMarkedPositions : List Extraction.ExtractionTarget

Equations

• TobaBatak.tbExtractionMarkedPositions = [Extraction.ExtractionTarget.subject]

def TobaBatak.tbExtractionDistinguishesPosition : Bool

Equations

• TobaBatak.tbExtractionDistinguishesPosition = true

Toba Batak voice system: two-way symmetrical (AV/OV).

Unlike Philippine-type languages (Tagalog: 4+ voices including
locative, instrumental), Toba Batak has only actor and object
voice. The system is symmetrical — neither voice is morphologically
basic.

Language: "Toba Batak".
Notes: Two-way symmetrical system ([erlewine-2018]). 

def TobaBatak.VoiceSystem.voices : List Voice.VoiceEntry

The voices of the Toba Batak system.

Equations

• TobaBatak.VoiceSystem.voices = [{ name := "Actor Voice", promotes := Voice.PivotTarget.agent }, { name := "Object Voice", promotes := Voice.PivotTarget.patient }]

def TobaBatak.VoiceSystem.symmetry : Voice.VoiceSystemSymmetry

System symmetry: symmetrical (neither voice is morphologically basic).

Equations

• TobaBatak.VoiceSystem.symmetry = Voice.VoiceSystemSymmetry.symmetrical

theorem TobaBatak.tb_voice_system_symmetrical : VoiceSystem.symmetry = Voice.VoiceSystemSymmetry.symmetrical

theorem TobaBatak.tb_voice_count : Voice.voiceCount VoiceSystem.voices = 2

theorem TobaBatak.tb_is_active_passive : Voice.isActivePassive VoiceSystem.voices

theorem TobaBatak.tb_promotes_agent : Voice.promotesRole VoiceSystem.voices Voice.PivotTarget.agent