fun {α} motive h1 h2 h3 =>
  match [], [] with
  | [], [] => h1 ()
  | x, [] => h2 x
  | x, x_1 =>
    h3 x
      x_1 : {α : Type} →
  (motive : List α → List α → Type) →
    (Unit → motive [] []) → ((x : List α) → motive x []) → ((x x_1 : List α) → motive x x_1) → motive [] []