任何 local operator 都是 inflationary 的,也就是
Proof [local-0]
{-# OPTIONS --safe --without-K #-} open import MLTT.Spartan open import UF.FunExt open import UF.PropTrunc open import UF.Subsingletons open import UF.SubtypeClassifier open import UF.Size open import UF.Logic module ag-GK6B (pt : propositional-truncations-exist) (fe : Fun-Ext) (pe : propext 𝓤) (ρ : propositional-resizing (𝓤 ⁺) 𝓤) where open Conjunction open Universal fe open Implication fe open import ag-5W9X pt fe pe ρ open is-local-operator
證明方式:若 p 成立則 p = ⊤(用到
propext),再由 unit 得到
j ⊤。
LO-infl : {j : Ω 𝓤 → Ω 𝓤} → is-local-operator j → (p : Ω 𝓤) → (p ⇒ j p) holds LO-infl {j} j-is-local-op p p-holds = transport (λ - → j - holds) ⊤=p j⊤ where -- p 成立,故 p = ⊤ ⊤=p : ⊤ = p ⊤=p = (holds-gives-equal-⊤ pe fe p p-holds) ⁻¹ -- 由 unit j⊤ : j ⊤ holds j⊤ = unit j-is-local-op ⋆