∀ {α : Type u_2} {ι' : Sort u_1} {p' : ι' → Prop} {s' : ι' → Set α} (_s : Set α)
  (motive : (∃ i, p' i ∧ s' i ⊆ _s) → Prop) (x : ∃ i, p' i ∧ s' i ⊆ _s),
  (∀ (_i' : ι') (hi' : p' _i') (hs : s' _i' ⊆ _s), motive ⋯) → motive x