∀ {C : Type u₁} [inst : CategoryTheory.Category.{v₁, u₁} C] {A : Type u₂} [inst_1 : CategoryTheory.Category.{v₂, u₂} A]
  (J : CategoryTheory.GrothendieckTopology C) (P : CategoryTheory.Functor Cᵒᵖ A),
  CategoryTheory.Presheaf.IsSheaf J P ↔
    ∀ ⦃X : C⦄, ∀ S ∈ J X, Nonempty (CategoryTheory.Limits.IsLimit (P.mapCone S.arrows.cocone.op))