module EmptySet where open import Logic data EmptySet : Set where -- nothing defined here: there are no constructors of this type. unique-map-from-empty-set : {X : Set} → EmptySet → X unique-map-from-empty-set = λ () the-empty-set-is-not-inhabited : ¬(inhabited EmptySet) the-empty-set-is-not-inhabited (∃-intro () *)