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{-# OPTIONS --cubical-compatible #-}
module Padova2025.Explorations.Uncountability.Lawvere
  {A X : Set} (f : A β†’ (A β†’ X)) (g : X β†’ X) where

Lawvere’s fixed point theorem

open import Padova2025.ProvingBasics.Equality.Base
open import Padova2025.ProvingBasics.Equality.General
open import Padova2025.ProvingBasics.Connectives.Existential
canary : A β†’ X
canary = {!!}
fix : βˆƒ[ a ] canary β‰— f a β†’ βˆƒ[ x ] g x ≑ x
fix = {!!}
fixβ‚€ : ((h : A β†’ X) β†’ βˆƒ[ a ] h β‰— f a) β†’ βˆƒ[ x ] g x ≑ x
fixβ‚€ = {!!}