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Linglib.Studies.Anaphora.Heim1982.Basic

Heim (1982): File Change Semantics and Anaphora #

@cite{heim-1982}

Formal analysis of cross-sentential anaphora using @cite{heim-1982}'s File Change Semantics. This study file connects the FCS theory (Theories/Semantics/Dynamic/FileChange/Basic.lean) to the empirical data in Phenomena/Anaphora/CrossSentential.lean.

Key Claims Formalized #

  1. Indefinites introduce discourse referents (new file cards): "A man walked in" opens a new dref that persists across sentences.

  2. Negation blocks dref export: "John didn't see a bird" confines the bird's dref to the scope of negation — it doesn't persist.

  3. Conjunction is sequential update: "A man walked in. He sat down." = F + [∃x. man(x) ∧ walkedIn(x)] + [satDown(x)].

  4. Novelty-Familiarity Condition: indefinites require novel indices; definites require familiar ones. Violations are presupposition failure (undefinedness), not falsehood.

  5. Truth criterion (C): φ is true w.r.t. F iff Sat(F + φ) is nonempty (@cite{heim-1982}, Ch III §3.2). This builds existential quantification into the notion of truth.

Connection to Empirical Data #

Each section below derives FCS predictions that account for specific data in CrossSententialAnaphora.

We work with a simple model: W = possible worlds, E = entities. Predicates are modeled as functions on possibilities.

"A man walked in. He sat down."

This accounts for CrossSententialAnaphora.indefinitePersists. The FCS analysis: the indefinite "a man" introduces dref x₁ into Dom(F). The pronoun "he" in the second sentence accesses x₁, which persists because no operator (negation, quantifier) has closed x₁'s scope.

The discourse is modeled as: F + [∃x₁. man(x₁) ∧ walkedIn(x₁)] + [satDown(x₁)] where ∃x₁ extends Dom(F) to include x₁.

noncomputable def Heim1982.aManWalkedIn {W : Type u_1} {E : Type u_2} (man walkedIn : EProp) (x : ) :

The indefinite "a man walked in" as an FCP: ∃x. man(x) ∧ walkedIn(x).

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    def Heim1982.heSatDown {W : Type u_1} {E : Type u_2} (satDown : EProp) (x : ) :

    "He sat down" as an FCP: satDown(x).

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      noncomputable def Heim1982.indefinitePersistsDiscourse {W : Type u_1} {E : Type u_2} (man walkedIn satDown : EProp) (x : ) :

      The full discourse "A man walked in. He sat down."

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        When x is novel, the indefinite FCP is defined (not a presupposition failure) — provided the body is total.

        theorem Heim1982.indef_adds_to_dom {W : Type u_1} {E : Type u_2} (x : ) (body : Semantics.Dynamic.FileChangeSemantics.FCP W E) (F F' : Semantics.Dynamic.FileChangeSemantics.HeimFile W E) (hnovel : F.novel x) (hres : Semantics.Dynamic.FileChangeSemantics.FCP.indef x body F = some F') (hbody_dom : ∀ (G G' : Semantics.Dynamic.FileChangeSemantics.HeimFile W E), body G = some G'x G.domx G'.dom) :
        x F'.dom

        After the indefinite, x is in the domain — provided the body preserves domain membership.

        This is the formal content of "indefinites introduce discourse referents" — the defining claim of @cite{heim-1982}.

        "John didn't see a bird. *It was singing."

        This accounts for CrossSententialAnaphora.standardNegationBlocks. The FCS analysis: negation closes the scope of the indefinite's dref. After F + [¬(∃x. bird(x) ∧ saw(j,x))], x is NOT in Dom — the negation's domain matches the input domain, not the extended one.

        A variable introduced inside negation is NOT in the output domain.

        Negation preserves the input domain (neg_preserves_dom), so a novel variable stays novel after negation — the dref is trapped inside the scope of ¬.

        The Novelty-Familiarity Condition is @cite{heim-1982}'s formalization of the indefinite/definite contrast (Ch III §2.2, p. 202):

        Violations cause undefinedness (presupposition failure), not falsehood. This is modeled by FCPs returning none.

        An indefinite with a familiar index causes presupposition failure.

        This accounts for why "*A man₁ walked in. A man₁ sat down." is infelicitous when the second indefinite reuses index 1.

        A definite with a novel index causes presupposition failure.

        This accounts for why "#He₁ sat down." is infelicitous at the start of a discourse (when no index 1 dref has been established).

        theorem Heim1982.indef_then_def_defined {W : Type u_1} {E : Type u_2} (x : ) (bodyIndef bodyDef : Semantics.Dynamic.FileChangeSemantics.FCP W E) (F : Semantics.Dynamic.FileChangeSemantics.HeimFile W E) (_hnovel : F.novel x) (F₁ : Semantics.Dynamic.FileChangeSemantics.HeimFile W E) (_hstep1 : Semantics.Dynamic.FileChangeSemantics.FCP.indef x bodyIndef F = some F₁) (hfam : F₁.familiar x) :

        An indefinite followed by a definite with the same index is well-defined: the indefinite makes x familiar for the definite.

        "A man₁ walked in. He₁ sat down." — after the indefinite introduces dref 1, the definite "he₁" finds it familiar.

        @cite{heim-1982}'s truth definition (Ch III §3.2, p. 214):

        (C) A formula φ is true w.r.t. a file F if F + φ is true, and false w.r.t. F if F + φ is false.

        A file is true iff Sat(F) ≠ ∅. So truth of φ w.r.t. F amounts to Sat(F + φ) being nonempty. Crucially, this builds existential quantification into the notion of truth, making Existential Closure dispensable (Ch III §3.1).

        Truth unfolds to: F + φ is defined and has nonempty Sat.

        Falsity unfolds to: F + φ is defined but has empty Sat.

        Support is idempotent: if F supports φ, then updating twice equals updating once.

        @cite{heim-1982}'s Principle (A): file change only eliminates possibilities, never adds them. This holds for atomic updates, negation, and their compositions.

        theorem Heim1982.neg_is_eliminative {W : Type u_1} {E : Type u_2} (φ : Semantics.Dynamic.FileChangeSemantics.FCP W E) (F F' : Semantics.Dynamic.FileChangeSemantics.HeimFile W E) (h : φ.neg F = some F') :
        F'.sat F.sat

        Negation is eliminative: Sat(F + ¬φ) ⊆ Sat(F).

        theorem Heim1982.seq_is_eliminative {W : Type u_1} {E : Type u_2} (φ ψ : Semantics.Dynamic.FileChangeSemantics.FCP W E) ( : ∀ (F F' : Semantics.Dynamic.FileChangeSemantics.HeimFile W E), φ F = some F'F'.sat F.sat) ( : ∀ (F F' : Semantics.Dynamic.FileChangeSemantics.HeimFile W E), ψ F = some F'F'.sat F.sat) (F F' : Semantics.Dynamic.FileChangeSemantics.HeimFile W E) (h : (φ +> ψ) F = some F') :
        F'.sat F.sat

        Sequential composition preserves eliminativity.

        We instantiate the FCS framework with a concrete finite model to verify the theory matches the empirical data from CrossSententialAnaphora.

        A simple model world type.

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          @[implicit_reducible]
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          def Heim1982.instReprExWorld.repr :
          ExWorldStd.Format
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            A simple entity type.

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              @[implicit_reducible]
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              def Heim1982.instReprExEntity.repr :
              ExEntityStd.Format
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                Starting file: no discourse referents, all possibilities.

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                  Each datum in CrossSententialAnaphora corresponds to a structural property of FCS. The per-datum theorems below verify that the FCS predictions match the empirical judgments.

                  FCS correctly records that indefinite persistence is felicitous.

                  FCS correctly records that negative quantifiers block.

                  FCS correctly records that definite reference is felicitous.

                  FCS correctly records that conditionals block antecedent drefs.

                  The structural FCS properties that account for each datum:

                  DatumFCS PropertyTheorem
                  indefinitePersistsindef extends Dom; body preserves itindef_adds_to_dom
                  universalBlocksUniversal = ∀ = ¬∃¬; negation preserves Domneg_blocks_dref
                  negativeBlocksNegation preserves Domneg_blocks_dref
                  standardNegationBlocksSame mechanismneg_blocks_dref
                  conditionalAntecedentConditional = ¬(φ ∧ ¬ψ); negation preserves Domcond_eq + neg_blocks_dref
                  definiteReferencedef_ requires familiarity; succeeds when dref establishedindef_then_def_defined