∀ {C : Type u₁} [inst : CategoryTheory.Category.{v₁, u₁} C] {D : Type u₂} [inst_1 : CategoryTheory.Category.{v₂, u₂} D]
  (S : CategoryTheory.Functor C D) (T : D) {P : CategoryTheory.ObjectProperty C},
  P.IsSeparating → (P.inverseImage (CategoryTheory.CostructuredArrow.proj S T)).IsSeparating