Documentation

Studies.Barker1995

Barker (1995): Possessive Descriptions #

Possessives are descriptions: a possessor, a possession relation — the noun's own relation for a relational noun (John's child), a contextually resolved one otherwise (John's stick) — and a sortal restrictor. Like definites they presuppose a unique maximal possessee per possessor; like indefinites they can introduce novel referents. In a quantificational possessive (most planets' rings) the quantifier binds the possessor and possessee variables together. Two consequences follow: quantification narrows to possessors that have a possessee, and the possessor-dominant and symmetric construals cannot be told apart truth-conditionally — uniqueness leaves one instance per case, which is the book's resolution of the perspective paradox.

Main statements #

References #

Decidability for the toy models #

@[instance_reducible]
instance Barker1995.instDecidableSomeOfFintypeOfDecidablePred_studies {α : Type u_1} [Fintype α] {R S : α → Prop} [DecidablePred R] [DecidablePred S] :
Decidable (Quantifier.GQ.some R S)
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The perspective paradox resolved (Ch. 4) #

With a unique possessee per possessor there is one instance per case, whether or not the possessee variable helps distinguish cases: counting possessor–possessee pairs agrees with counting possessors.

theorem Barker1995.symmetric_iff_possessor_dominant {α : Type u_1} (C A B : α → Prop) (R : α → α → Prop) (huniq : ∀ (x y y' : α), A y → R x y → A y' → R x y' → y = y') :
(Quantifier.GQ.most (fun (p : α × α) => C p.1 ∧ A p.2 ∧ R p.1 p.2) fun (p : α × α) => B p.2) ↔ Possession.Poss Quantifier.GQ.most C Quantifier.GQ.some R A B

The uniqueness presupposition neutralizes the perspective paradox (Ch. 4): when each possessor has at most one possessee, most over possessor–possessee pairs (the symmetric construal) and Poss most (the possessor-dominant construal) have the same truth conditions.

Narrowing: the planets and their rings (Ch. 4) #

Nine planets, of which only Saturn, Neptune and Uranus have rings; Saturn's and Neptune's rings are icy, Uranus's are not. Most planets' rings are made of ice is judged true — the quantification ranges only over the three ringed planets. Entities 0–8 are the planets, 9–11 their rings.

@[reducible, inline]
abbrev Barker1995.isPlanet :
Fin 12 → Prop
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Instances For
    @[reducible, inline]
    abbrev Barker1995.isRing :
    Fin 12 → Prop
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    Instances For
      @[reducible, inline]
      abbrev Barker1995.hasRing :
      Fin 12 → Fin 12 → Prop
      Equations
      Instances For
        @[reducible, inline]
        abbrev Barker1995.isIcy :
        Fin 12 → Prop
        Equations
        Instances For

          Most planets' rings are made of ice is true: Poss narrows the domain to the three ringed planets, two of which have icy rings.

          theorem Barker1995.not_unnarrowed :
          ¬Quantifier.GQ.most isPlanet fun (x : Fin 12) => Quantifier.GQ.some (fun (y : Fin 12) => isRing y ∧ hasRing x y) isIcy

          Without narrowing, the quantification is false: only two of the nine planets have an icy ring.

          No possessee-dominant reading (Ch. 4) #

          Five people and three colors: one favors red, one yellow, three blue. Most people's favorite color is blue is true counting people (3 of 5) and would be false counting colors (1 of 3); the color-counting reading does not exist. Entities 0–4 are the people; 5, 6, 7 are red, yellow, blue.

          @[reducible, inline]
          abbrev Barker1995.isPerson :
          Fin 8 → Prop
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          Instances For
            @[reducible, inline]
            abbrev Barker1995.isColor :
            Fin 8 → Prop
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            Instances For
              @[reducible, inline]
              abbrev Barker1995.favors :
              Fin 8 → Fin 8 → Prop
              Equations
              • Barker1995.favors x y = (x = 0 ∧ y = 5 ∨ x = 1 ∧ y = 6 ∨ (x = 2 ∨ x = 3 ∨ x = 4) ∧ y = 7)
              Instances For
                @[reducible, inline]
                abbrev Barker1995.isBlue :
                Fin 8 → Prop
                Equations
                Instances For

                  Most people's favorite color is blue, counting people, is true, with 3 of 5.

                  theorem Barker1995.not_favorite_color_possessee_dominant :
                  ¬Quantifier.GQ.most (fun (c : Fin 8) => isColor c ∧ ∃ (p : Fin 8), isPerson p ∧ favors p c) isBlue

                  Counting favored colors instead of people would make the sentence false — the reading English does not have.

                  theorem Barker1995.favors_unique (x y y' : Fin 8) :
                  isColor y → favors x y → isColor y' → favors x y' → y = y'

                  Each person favors at most one color.

                  theorem Barker1995.favorite_color_symmetric :
                  Quantifier.GQ.most (fun (p : Fin 8 × Fin 8) => isPerson p.1 ∧ isColor p.2 ∧ favors p.1 p.2) fun (p : Fin 8 × Fin 8) => isBlue p.2

                  The symmetric construal of the favorite-color sentence, derived from the possessor-dominant one through symmetric_iff_possessor_dominant.

                  Definiteness (Ch. 2) #

                  A definite possessive presupposes a unique possessee: in a model where the boy 0 owns exactly the cat 1, the possessee predicate of the boy's cat has one satisfier.

                  theorem Barker1995.theBoysCat_unique :
                  ∃! y : Fin 3, Possession.π (fun (x : Fin 3) => x = 1) (fun (x y : Fin 3) => x = 0 ∧ y = 1) 0 y

                  Narrowing with a single possessor #

                  For a single possessor, narrowing surfaces as existential import: Mercury's rings are icy fails because Mercury (planet 3) has no ring.