∀ {x : CategoryTheory.Cat} (x_1 x_2 : ↑x) (motive : (CategoryTheory.isIsomorphicSetoid ↑x) x_1 x_2 → Prop)
  (x_3 : (CategoryTheory.isIsomorphicSetoid ↑x) x_1 x_2), (∀ (f : x_1 ≅ x_2), motive ⋯) → motive x_3