∀ {α : Type u_1} {p q : α → Bool} (a : α) (l : List α)
  (motive : ((p a = true → q a = true) ∧ ∀ x ∈ l, p x = true → q x = true) → Prop)
  (h : (p a = true → q a = true) ∧ ∀ x ∈ l, p x = true → q x = true),
  (∀ (ha : p a = true → q a = true) (hl : ∀ x ∈ l, p x = true → q x = true), motive ⋯) → motive h