∀ {α : Type u_1} (motive : Lists' α true → Lists' α true → Sort u_2) (x : Lists' α true)
  (h_1 : (x : Lists' α true) → motive Lists'.nil x)
  (h_2 : (b : Bool) → (a : Lists' α b) → (l₁ l₂ : Lists' α true) → motive (a.cons' l₁) l₂),
  (match Lists'.nil, x with
    | Lists'.nil, x => h_1 x
    | a.cons' l₁, l₂ => h_2 b a l₁ l₂) =
    h_1 x