module Exercises1 where open import Agda.Primitive open import foundation-core.empty-types open import foundation-core.equivalences open import foundation-core.negation open import foundation.natural-numbers open import foundation.dependent-pair-types open import foundation.identity-types open import foundation.univalence open import foundation.sections open import foundation.retractions _≡_ = _=_ ⊥ = empty equal-to-zero : {A : Set} (f : ¬ A) → A ≡ ⊥ equal-to-zero {A} f = eq-equiv A ⊥ eqv where s : section f s = (λ ()) , λ x → ex-falso x r : retraction f r = (λ ()) , λ x → ex-falso (f x) eqv : A ≃ ⊥ eqv = f , s , r asdf : 0 ≡ 1