∀ {C : Type u_2} [inst : CategoryTheory.Category.{u_1, u_2} C] {X Y : C} (π : Y ⟶ X) ⦃V : C⦄ ⦃f : V ⟶ X⦄
  (motive :
    (CategoryTheory.Sieve.generate
            (CategoryTheory.Presieve.ofArrows (fun x => Y) fun x =>
              match x with
              | PUnit.unit => π)).arrows
        f →
      Prop)
  (h :
    (CategoryTheory.Sieve.generate
          (CategoryTheory.Presieve.ofArrows (fun x => Y) fun x =>
            match x with
            | PUnit.unit => π)).arrows
      f),
  (∀ (Y₁ : C) (h : V ⟶ Y₁) (g : Y₁ ⟶ X)
      (hY :
        CategoryTheory.Presieve.ofArrows (fun x => Y)
          (fun x =>
            match x with
            | PUnit.unit => π)
          g)
      (hf : CategoryTheory.CategoryStruct.comp h g = f), motive ⋯) →
    motive h