{motive : Mathlib.Meta.Positivity.OrderRel✝ → Sort u} →
  (ctorIdx : ℕ) →
    (t : Mathlib.Meta.Positivity.OrderRel✝¹) →
      ctorIdx = Mathlib.Meta.Positivity.OrderRel.ctorIdx✝ t →
        Mathlib.Meta.Positivity.OrderRel.ctorElimType✝ ctorIdx → motive t