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Linglib.Phenomena.Quantification.Studies.Cooper2023

Cooper (2023) Ch. 7 β€” Witness-based Quantification #

@cite{cooper-2023} @cite{barwise-cooper-1981} @cite{van-benthem-1984}

@cite{cooper-2023} Chapter 7 replaces classical set-theoretic GQ denotations (cf. Core.Quantification.GQ) with witness sets β€” finite sets of individuals satisfying cardinality conditions specific to each quantifier.

This study formalises Ch. 7 directly. It was formerly substrate at Theories/Semantics/TypeTheoretic/Quantification.lean but is genuinely a single-paper Cooper-textbook replication: only LuckingGinzburg2022 and Phenomena/Anaphora/Studies/Cooper2023 consume it externally, and both are themselves Cooper-2023-anchored discussions.

Key contributions:

Β§7.2.3 Pure properties, purification, and 𝔗(P) (eqs 11–19) #

A parametric property P : PPpty E has background P.Bg and foreground P.fg. P is pure when Bg is trivial (β‰… Unit): no extra background constraints.

Purification folds background conditions into the property body:

A parametric property is pure when its background is trivial. Β§7.2.3, eq (7a): P.bg has only the x-field.

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    The type of witnesses for property P. Β§7.2.3, eq (17): a : 𝔗(P) iff 𝔓(P){a} is witnessed. For a pure property, 𝔗(P) = {a : E // Nonempty (P a)}.

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      Existential purification of a parametric property. Β§7.2.3, eq (12): 𝔓(P) merges background conditions into the body via existential quantification. 𝔓(P)(a) = Ξ£ (c : Bg), fg c a.

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        Universal purification of a parametric property. Β§7.2.3, eq (13): 𝔓ʸ(P) universally quantifies over background contexts. Used for strong donkey readings.

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          Notation for purification operators.

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              For a trivial parametric property, purification adds only a Unit factor.

              theorem Phenomena.Quantification.Studies.Cooper2023.purify_nonempty_iff {E : Type} (P : Semantics.TypeTheoretic.PPpty E) (a : E) :
              Nonempty (purify P a) ↔ βˆƒ (c : P.Bg), Nonempty (P.fg c a)

              Purified property is witnessed iff the original is witnessable under some context.

              theorem Phenomena.Quantification.Studies.Cooper2023.purifyUniv_nonempty_iff {E : Type} (P : Semantics.TypeTheoretic.PPpty E) (a : E) :
              Nonempty (purifyUniv P a) ↔ βˆ€ (c : P.Bg), Nonempty (P.fg c a)

              Universal purification: witnessed iff property holds under all contexts.

              Β§7.2.4 Types of witness sets for quantifiers (eqs 20–35) #

              Each quantifier q defines a type qΚ·(P) of witness sets. X : qΚ·(P) iff (1) X βŠ† extension of P, and (2) a cardinality condition.

              All witness set types share a common subset condition (X βŠ† [↓P]). This structural requirement is what derives conservativity from the witness architecture β€” it's not stipulated as in @cite{barwise-cooper-1981}.

              def Phenomena.Quantification.Studies.Cooper2023.fullExtFinset {E : Type} [Fintype E] (P : E β†’ Prop) [DecidablePred P] :
              Finset E

              Computable extension of P as a Finset. Cooper's [𝔗(P)] or [↓P].

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                structure Phenomena.Quantification.Studies.Cooper2023.WitnessSet {E : Type} (P : E β†’ Prop) (X : Finset E) :

                Base witness set condition: X βŠ† extension of P. Β§7.2.4: every witness set type requires this.

                • subset (a : E) : a ∈ X β†’ P a
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                  existΚ·(P): singleton witness set. Eq (21).

                  • subset (a : E) : a ∈ X β†’ P a
                  • card_eq : X.card = 1
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                    exist_plΚ·(P): plural some, |X| β‰₯ 2. Eq (22).

                    • subset (a : E) : a ∈ X β†’ P a
                    • card_ge : X.card β‰₯ 2
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                      def Phenomena.Quantification.Studies.Cooper2023.IsNoW {E : Type} (_P : E β†’ Prop) (X : Finset E) :

                      noΚ·(P): empty set. Eqs (23–24).

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                        def Phenomena.Quantification.Studies.Cooper2023.IsEveryW {E : Type} [Fintype E] (P : E β†’ Prop) [DecidablePred P] (X : Finset E) :

                        everyΚ·(P): the full extension. Eqs (25–26).

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                          structure Phenomena.Quantification.Studies.Cooper2023.IsMostW {E : Type} [Fintype E] (P : E β†’ Prop) [DecidablePred P] (ΞΈ_num ΞΈ_denom : β„•) (X : Finset E) extends Phenomena.Quantification.Studies.Cooper2023.WitnessSet P X :

                          mostΚ·(P): proportional, |X|/|[↓P]| β‰₯ ΞΈ. Eq (29). Stated as cross-multiplication: X.card * denom β‰₯ num * ext.card.

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                            many_aΚ·(P): absolute threshold, |X| β‰₯ ΞΈ. Eq (30).

                            • subset (a : E) : a ∈ X β†’ P a
                            • card_ge : X.card β‰₯ ΞΈ
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                              structure Phenomena.Quantification.Studies.Cooper2023.IsManyPropW {E : Type} [Fintype E] (P : E β†’ Prop) [DecidablePred P] (ΞΈ_num ΞΈ_denom : β„•) (X : Finset E) extends Phenomena.Quantification.Studies.Cooper2023.WitnessSet P X :

                              many_pΚ·(P): proportional, |X|/|[↓P]| β‰₯ ΞΈ. Eq (31).

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                                few_aΚ·(P): absolute, |X| ≀ ΞΈ. Eq (32).

                                • subset (a : E) : a ∈ X β†’ P a
                                • card_le : X.card ≀ ΞΈ
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                                  structure Phenomena.Quantification.Studies.Cooper2023.IsFewPropW {E : Type} [Fintype E] (P : E β†’ Prop) [DecidablePred P] (ΞΈ_num ΞΈ_denom : β„•) (X : Finset E) extends Phenomena.Quantification.Studies.Cooper2023.WitnessSet P X :

                                  few_pΚ·(P): proportional, |X|/|[↓P]| ≀ ΞΈ. Eq (33).

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                                    a_few_aΚ·(P): absolute, |X| β‰₯ ΞΈ (same threshold as few, reversed direction). Eq (34).

                                    • subset (a : E) : a ∈ X β†’ P a
                                    • card_ge : X.card β‰₯ ΞΈ
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                                      structure Phenomena.Quantification.Studies.Cooper2023.IsAFewPropW {E : Type} [Fintype E] (P : E β†’ Prop) [DecidablePred P] (ΞΈ_num ΞΈ_denom : β„•) (X : Finset E) extends Phenomena.Quantification.Studies.Cooper2023.WitnessSet P X :

                                      a_few_pΚ·(P): proportional, |X|/|[↓P]| β‰₯ ΞΈ. Eq (35).

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                                        structure Phenomena.Quantification.Studies.Cooper2023.IsCompFewAbsW {E : Type} [Fintype E] (P : E β†’ Prop) [DecidablePred P] (ΞΈ : β„•) (X : Finset E) extends Phenomena.Quantification.Studies.Cooper2023.WitnessSet P X :

                                        Complement witness set for few (absolute). Eq (81). XΜ„ : fewΜ„Κ·_a(P) iff |X| β‰₯ |[𝔗(P)]| βˆ’ ΞΈ. Predicts COMPSET anaphora.

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                                          structure Phenomena.Quantification.Studies.Cooper2023.IsCompFewPropW {E : Type} [Fintype E] (P : E β†’ Prop) [DecidablePred P] (ΞΈ_num ΞΈ_denom : β„•) (X : Finset E) extends Phenomena.Quantification.Studies.Cooper2023.WitnessSet P X :

                                          Complement witness set for few (proportional). Eq (82).

                                          • subset (a : E) : a ∈ X β†’ P a
                                          • extPos : (fullExtFinset P).card > 0
                                          • proportion : X.card * ΞΈ_denom β‰₯ (ΞΈ_denom - ΞΈ_num) * (fullExtFinset P).card
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                                            theorem Phenomena.Quantification.Studies.Cooper2023.isNoW_iff_empty {E : Type} (P : E β†’ Prop) (X : Finset E) :
                                            IsNoW P X ↔ X = βˆ…

                                            noΚ· has exactly one witness set: βˆ….

                                            theorem Phenomena.Quantification.Studies.Cooper2023.isEveryW_iff {E : Type} [DecidableEq E] [Fintype E] (P : E β†’ Prop) [DecidablePred P] (X : Finset E) :
                                            IsEveryW P X ↔ X = fullExtFinset P

                                            everyΚ· has exactly one witness set: the full extension.

                                            Β§7.3 Austinian propositions and probabilistic quantification (eqs 36–58) #

                                            Probabilities for quantifiers are estimated from an agent's finite experience base 𝔉 β€” a set of Austinian propositions recording categorical judgments [sit=a, type=T].

                                            Frequentist conditional probability: p_𝔉(T₁‖Tβ‚‚) = |[Tβ‚βˆ§Tβ‚‚]_𝔉| / |[Tβ‚‚]_𝔉|

                                            structure Phenomena.Quantification.Studies.Cooper2023.ExperienceBase (E P : Type) [DecidableEq E] [DecidableEq P] :

                                            An experience base: the agent's memory of categorical judgments. Β§7.3, eq (37): 𝔉 is a finite set of [sit=a, type=T] records. Parameterized over entity type E and predicate type P.

                                            • judgments : Finset (E Γ— P)

                                              The observed entity-predicate judgments

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                                              def Phenomena.Quantification.Studies.Cooper2023.ExperienceBase.ext {E P : Type} [DecidableEq E] [DecidableEq P] (𝔉 : ExperienceBase E P) (p : P) :
                                              Finset E

                                              Extension of predicate p relative to 𝔉. Β§7.3, eq (38): [T]_𝔉 = {a | a :_𝔉 T}.

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                                              • 𝔉.ext p = Finset.image Prod.fst ({x ∈ 𝔉.judgments | x.2 = p})
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                                                def Phenomena.Quantification.Studies.Cooper2023.ExperienceBase.jointExt {E P : Type} [DecidableEq E] [DecidableEq P] (𝔉 : ExperienceBase E P) (p q : P) :
                                                Finset E

                                                Joint extension: entities classified under both predicates.

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                                                  def Phenomena.Quantification.Studies.Cooper2023.ExperienceBase.condProb {E P : Type} [DecidableEq E] [DecidableEq P] (𝔉 : ExperienceBase E P) (p q : P) :
                                                  β„• Γ— β„•

                                                  Frequentist conditional probability estimate (as numerator/denominator). Β§7.3, eq (36): p_𝔉(T₁‖Tβ‚‚) = |[Tβ‚βˆ§Tβ‚‚]_𝔉| / |[Tβ‚‚]_𝔉|.

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                                                    def Phenomena.Quantification.Studies.Cooper2023.ExperienceBase.reliability {E P : Type} [DecidableEq E] [DecidableEq P] (𝔉 : ExperienceBase E P) (p q : P) :
                                                    β„•

                                                    Reliability of a probability estimate (count before log). Β§7.3, eq (40): reliability = ln min(|[T₁]_𝔉|, |[Tβ‚‚]_𝔉|).

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                                                      Β§7.4 Witness conditions for quantificational ptypes (eqs 59–90) #

                                                      The central theoretical contribution: how quantifiers evaluate. Each q(P,Q) is witnessed by a pair (X, f) where X is a witness set and f maps witnesses to Q-evidence.

                                                      Two patterns:

                                                      structure Phenomena.Quantification.Studies.Cooper2023.GeneralWC_Incr {E : Type} (P Q : Semantics.TypeTheoretic.Ppty E) (isWS : Finset E β†’ Prop) [DecidableEq E] :

                                                      General witness condition for monotone ↑ quantifiers. Β§7.4, eq (59a): s : q(P,Q) iff s : [X : qΚ·(P), f : (a : 𝔗(X)) β†’ 𝔓(Q){a}] Each member of X must individually witness Q.

                                                      • X : Finset E
                                                      • witnessOK : isWS self.X
                                                      • f (a : E) : a ∈ self.X β†’ Q a
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                                                        structure Phenomena.Quantification.Studies.Cooper2023.GeneralWC_Decr {E : Type} (P Q : Semantics.TypeTheoretic.Ppty E) (isWS : Finset E β†’ Prop) [DecidableEq E] :

                                                        General witness condition for monotone ↓ quantifiers. Β§7.4, eq (59b): Every entity with both P and Q lands in X.

                                                        • X : Finset E
                                                        • witnessOK : isWS self.X
                                                        • f (a : E) : Nonempty (P a) β†’ Nonempty (Q a) β†’ a ∈ self.X
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                                                          Particular witness condition for exist(P,Q). Eq (63). s : exist(P,Q) iff s : [x : 𝔗(P), e : 𝔓(Q){x}] The x-field enables REFSET (singular) anaphora: "A dog barked. It heard an intruder."

                                                          • x : E
                                                          • pWit : P self.x
                                                          • qWit : Q self.x
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                                                            Particular witness condition for no(P,Q). Eq (70). Every P-entity fails to have Q (type negation). everyΚ·(P) as witness set predicts MAXSET anaphora: "No dog barked. They (= the dogs) were all asleep."

                                                            • f (a : E) : βˆ€ (a✝ : P a), IsEmpty (Q a)
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                                                              Particular witness condition for few with complement. Eqs (85–86). Uses complement witness set: P-entities lacking Q. Predicts COMPSET anaphora: "Few dogs barked. They (= non-barking dogs) slept through."

                                                              • X : Finset E
                                                              • allP (a : E) : a ∈ self.X β†’ Nonempty (P a)
                                                              • allNotQ (a : E) : a ∈ self.X β†’ IsEmpty (Q a)
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                                                                def Phenomena.Quantification.Studies.Cooper2023.particular_exist_implies_general {E : Type} [DecidableEq E] (P Q : Semantics.TypeTheoretic.Ppty E) (h : ParticularWC_Exist P Q) (Pd : E β†’ Prop) (hPd : βˆ€ (a : E), Pd a ↔ Nonempty (P a)) :

                                                                The particular exist condition implies the general one (with singleton X). Β§7.4: the particular condition "provides a component in the witness (in the 'x'-field) which can be picked up on by singular anaphora."

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                                                                  Anaphora set predictions per quantifier. Β§7.4.1: witness structure determines available anaphora.

                                                                  • refset : AnaphoraRef

                                                                    REFSET: reference to the witness individual/set. "A dog barked. It (= that dog) heard an intruder."

                                                                  • maxset : AnaphoraRef

                                                                    MAXSET: reference to the full extension. "Every dog barked. They (= the dogs) heard an intruder."

                                                                  • compset : AnaphoraRef

                                                                    COMPSET: reference to the complement witness set (for few). "Few dogs barked. They (= the non-barking dogs) slept through."

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                                                                      Quantifier names for typed dispatch. Β§7.4.1: the quantifiers of the English fragment.

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                                                                          Β§7.5 Long distance dependencies (eqs 114–158) #

                                                                          Cooper extends contexts with gap and wh-assignments to handle extraction, relative clauses, and wh-questions.

                                                                          Context with gap assignment. Β§7.5: Cntxt = [𝔰, 𝔀, 𝔠] (the 3-field gap-aware context Cooper introduces around the slash-category discussion).

                                                                          • 𝔰 : AssgnType
                                                                          • 𝔀 : AssgnType
                                                                          • 𝔠 : CntxtType
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                                                                            Full context with wh- and gap assignments. Β§7.5: Cntxt = [𝔰, 𝔴, 𝔀, 𝔠] (the 4-field context for wh-extraction; Cooper's Ch. 8 eq (10) extends this to the 5-field {q, 𝔰, 𝔴, 𝔀, 𝔠}).

                                                                            • 𝔰 : AssgnType
                                                                            • 𝔴 : AssgnType
                                                                            • 𝔀 : AssgnType
                                                                            • 𝔠 : CntxtType
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                                                                              Slash category: S/i is a sentence missing constituent at gap i. Β§7.5, eq (149): the TTR analogue of slash categories.

                                                                              • mother : String
                                                                              • gapIdx : β„•
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                                                                                def Phenomena.Quantification.Studies.Cooper2023.instDecidableEqSlashCat.decEq (x✝ x✝¹ : SlashCat) :
                                                                                Decidable (x✝ = x✝¹)
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                                                                                    WhNP condition. Β§7.5, eq (149a): Οƒ : WhNP iff Οƒ : NP and Ξ©.bg βŠ‘ [𝔴:[xα΅’:Ind]] for some i.

                                                                                    • whIdx : β„•
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                                                                                      Property conjunction. Β§7.5, eq (153): P₁ & Pβ‚‚ for relative clauses. "child who Sam hugged" = child ∧ hugged-by-Sam.

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                                                                                        theorem Phenomena.Quantification.Studies.Cooper2023.pptyConj_nonempty {E : Type} (P₁ Pβ‚‚ : Semantics.TypeTheoretic.Ppty E) (x : E) (h₁ : Nonempty (P₁ x)) (hβ‚‚ : Nonempty (Pβ‚‚ x)) :
                                                                                        Nonempty (pptyConj P₁ Pβ‚‚ x)

                                                                                        Property conjunction preserves witnesses.

                                                                                        Type-indexed property: properties of objects of type T. Β§7.5, eq (152): P : α΅€Ppty iff P.bg βŠ‘ [x:T].

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                                                                                          Phenomena #

                                                                                          Example: "a dog barks" (Β§7.4.1).

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                                                                                              The full extension of isDog is {fido, rex, spot}.

                                                                                              Particular witness for "a dog barks": fido barks and is a dog.

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                                                                                                "No dog barks" fails: fido is a dog that barks.

                                                                                                Predicate type for the dog example.

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                                                                                                    Simple experience base: 3 dogs observed, 2 bark.

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                                                                                                      Structural theorems #

                                                                                                      Key theoretical claims of Ch 7, connecting witness-based quantification to classical GQ properties and each other.

                                                                                                      Bridge: witness-based β†’ GQ #

                                                                                                      Every witness set type induces a classical GQ by existentially quantifying over witness sets. This is the fundamental connection between Cooper's type-theoretic quantifiers and Barwise & Cooper's set-theoretic ones.

                                                                                                      The GQ induced by existential witness sets. exist(A,B) iff some element satisfies both A and B.

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                                                                                                        The GQ induced by universal witness sets. every(A,B) iff every A-element also satisfies B.

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                                                                                                          Conservativity from witness structure #

                                                                                                          All witness set types require X βŠ† [↓P] (the subset condition). This structurally entails conservativity: q(P,Q) depends only on P ∩ Q, never on Q outside P. Β§7.2.4.

                                                                                                          This is significant because conservativity is stipulated as an axiom in @cite{barwise-cooper-1981} but derived from the witness architecture.

                                                                                                          Conservativity of witnessGQ_exist: follows from the subset condition in IsExistW. Cooper's key argument: conservativity is structural, not stipulated.

                                                                                                          Bridge: witness quantification ↔ extensional truth #

                                                                                                          Cooper's witness-based quantifiers (type-theoretic) compute the same truth values as the extensional denotations in Semantics.Montague/Quantifier. This bridges the three layers of quantification: Core.Quantification (logical properties) ← proved via conservativity above Semantics.Montague (extensional denotations) ← proved via equivalence below TTR (witness-based) ← definitions above

                                                                                                          theorem Phenomena.Quantification.Studies.Cooper2023.particular_exist_iff_witnessGQ {E : Type} (P Q : E β†’ Prop) :
                                                                                                          (βˆƒ (x : E), P x ∧ Q x) ↔ witnessGQ_exist P Q

                                                                                                          TTR's structured particular witness condition is equivalent to the existential GQ being true. This is the key grounding theorem: ParticularWC_Exist P Q is inhabited iff witnessGQ_exist holds.

                                                                                                          theorem Phenomena.Quantification.Studies.Cooper2023.universal_iff_witnessGQ {E : Type} (P Q : E β†’ Prop) :
                                                                                                          (βˆ€ (x : E), P x β†’ Q x) ↔ witnessGQ_every P Q

                                                                                                          The universal condition is equivalent to the universal GQ being true.

                                                                                                          theorem Phenomena.Quantification.Studies.Cooper2023.particularWC_to_witnessGQ {E : Type} [DecidableEq E] {P Q : Semantics.TypeTheoretic.Ppty E} (w : ParticularWC_Exist P Q) (Pd Qd : E β†’ Prop) (hP : βˆ€ (a : E), Pd a ↔ Nonempty (P a)) (hQ : βˆ€ (a : E), Qd a ↔ Nonempty (Q a)) :

                                                                                                          TTR's ParticularWC_Exist gives a constructive witness for the existential GQ.

                                                                                                          theorem Phenomena.Quantification.Studies.Cooper2023.particularWC_no_to_witnessGQ {E : Type} [DecidableEq E] {P Q : Semantics.TypeTheoretic.Ppty E} (w : ParticularWC_No P Q) (Pd Qd : E β†’ Prop) (hP : βˆ€ (a : E), Pd a ↔ Nonempty (P a)) (hQ : βˆ€ (a : E), Qd a ↔ Nonempty (Q a)) :
                                                                                                          witnessGQ_every Pd fun (x : E) => Β¬Qd x

                                                                                                          TTR's ParticularWC_No implies the universal GQ with negated scope.

                                                                                                          Purification and donkey anaphora #

                                                                                                          Existential purification 𝔓 gives weak donkey readings; universal purification 𝔓ʸ gives strong donkey readings. For pure properties (trivial Bg), both collapse to identity.

                                                                                                          theorem Phenomena.Quantification.Studies.Cooper2023.purify_pure_equiv {E : Type} (P : Semantics.TypeTheoretic.PPpty E) (hPure : PPpty.isPure P) (a : E) :
                                                                                                          Nonempty (purify P a) ↔ Nonempty (P.fg β‹―.some a)

                                                                                                          Purification of a pure property is equivalent to the original. Β§7.2.3: if P.Bg β‰… Unit, then 𝔓(P) ≃ P.fg.

                                                                                                          theorem Phenomena.Quantification.Studies.Cooper2023.purifyUniv_pure_equiv {E : Type} (P : Semantics.TypeTheoretic.PPpty E) (hPure : PPpty.isPure P) (a : E) :
                                                                                                          Nonempty (purifyUniv P a) ↔ Nonempty (P.fg β‹―.some a)

                                                                                                          Universal purification of a pure property also collapses.

                                                                                                          For pure properties, weak and strong donkey readings agree. Β§7.2.3: the distinction only matters when Bg is non-trivial.

                                                                                                          Particular β†’ general witness condition lifting #

                                                                                                          Each particular witness condition implies the corresponding general one. The particular conditions are preferred because they expose finer-grained structure for anaphora resolution.

                                                                                                          Particular no implies general (decreasing) no. Β§7.4, eqs (70) β†’ (59b): if every P-entity lacks Q, then the empty witness set satisfies the decreasing condition (vacuously: no entity has both P and Q).

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                                                                                                            Complement witness sets and the few/a_few contrast #

                                                                                                            Cooper's key empirical claim (Β§7.4.2): few and a_few share the same cardinality threshold but differ in anaphora predictions because few (downward monotone) supports complement witness sets while a_few (upward monotone) does not.

                                                                                                            theorem Phenomena.Quantification.Studies.Cooper2023.comp_witness_card {E : Type} [DecidableEq E] [Fintype E] (P : E β†’ Prop) [DecidablePred P] (X : Finset E) (_hSub : βˆ€ a ∈ X, P a) (ΞΈ : β„•) (hFew : X.card ≀ ΞΈ) (hXsub : X βŠ† fullExtFinset P) :
                                                                                                            (fullExtFinset P \ X).card β‰₯ (fullExtFinset P).card - ΞΈ

                                                                                                            The complement witness set for few satisfies the complement cardinality condition. Β§7.4.2, eq (81): XΜ„ = 𝔗(P) \ X.

                                                                                                            theorem Phenomena.Quantification.Studies.Cooper2023.few_comp_partition {E : Type} [DecidableEq E] [Fintype E] (P : E β†’ Prop) [DecidablePred P] (X : Finset E) (hX : X βŠ† fullExtFinset P) :
                                                                                                            X βˆͺ fullExtFinset P \ X = fullExtFinset P

                                                                                                            few_a and its complement partition the full extension. Β§7.4.2: X βˆͺ XΜ„ = 𝔗(P).

                                                                                                            Record path subtraction (βŠ–) for LDD #

                                                                                                            Β§7.5, eq (118): T βŠ– Ο€ removes a field from a record type. This is the operation underlying gap-threading: a transitive verb type minus its object field yields the gap-containing type.

                                                                                                            def Phenomena.Quantification.Studies.Cooper2023.recSubtract (fields : List (String Γ— Type)) (path : String) :
                                                                                                            List (String Γ— Type)

                                                                                                            Record path subtraction: remove a named field from a record. Β§7.5, eq (118): T βŠ– Ο€ removes field Ο€ from T. Encoded as filtering on a list of (label, type) pairs.

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                                                                                                              theorem Phenomena.Quantification.Studies.Cooper2023.recSubtract_removes (fields : List (String Γ— Type)) (path : String) (p : String Γ— Type) :
                                                                                                              p ∈ recSubtract fields path β†’ p.1 β‰  path

                                                                                                              Subtraction removes exactly the targeted field.

                                                                                                              theorem Phenomena.Quantification.Studies.Cooper2023.recSubtract_preserves (fields : List (String Γ— Type)) (path label : String) (h : label β‰  path) (p : String Γ— Type) :
                                                                                                              p ∈ fields β†’ p.1 = label β†’ p ∈ recSubtract fields path

                                                                                                              Subtraction preserves other fields.

                                                                                                              Dependency families and generalization (T^Ο€) #

                                                                                                              Β§7.5, eq (133): T^Ο€ = Ξ»v.[T βŠ– Ο€ ∧ {Ο€ : v}]. A dependency family abstracts over the gap, yielding a function from entities to record types. This is the TTR analogue of lambda-abstraction over a trace in transformational grammar.

                                                                                                              Dependency family: abstract over a gap to get a property. Β§7.5, eq (133): T^Ο€(v) fills gap Ο€ with v.

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                                                                                                                Merging a dependency family with a quantifier yields a scope-taking constituent. Β§7.5, eq (137): "which child Sam hugged" = Quant derived from T^Ο€.

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                                                                                                                  Monotonicity from witness conditions #

                                                                                                                  Β§7.4: the general witness condition for ↑ quantifiers (59a) uses existential evidence per witness (f maps each to Q-evidence), while ↓ quantifiers (59b) use universal containment (every P∧Q entity is in X). This structural difference predicts monotonicity direction.

                                                                                                                  def Phenomena.Quantification.Studies.Cooper2023.generalWC_incr_mono {E : Type} [DecidableEq E] (P Q Q' : Semantics.TypeTheoretic.Ppty E) (isWS : Finset E β†’ Prop) (embed : (a : E) β†’ Q a β†’ Q' a) (w : GeneralWC_Incr P Q isWS) :
                                                                                                                  GeneralWC_Incr P Q' isWS

                                                                                                                  Upward monotonicity of the increasing witness condition: if Q βŠ† Q' (at Type level), any witness for Q also witnesses Q'. Β§7.4, consequence of (59a).

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                                                                                                                    def Phenomena.Quantification.Studies.Cooper2023.generalWC_decr_mono {E : Type} [DecidableEq E] (P Q Q' : Semantics.TypeTheoretic.Ppty E) (isWS : Finset E β†’ Prop) (embed : (a : E) β†’ Q' a β†’ Q a) (w : GeneralWC_Decr P Q isWS) :
                                                                                                                    GeneralWC_Decr P Q' isWS

                                                                                                                    Downward monotonicity of the decreasing witness condition: if Q' βŠ† Q, then the decreasing condition on Q implies it on Q'. Β§7.4, consequence of (59b).

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