∀ (motive : ℕ → ℕ → ℕ → Prop) (x x_1 x_2 : ℕ),
  (∀ (x x_3 : ℕ), motive 0 x x_3) →
    (∀ (x x_3 : ℕ), motive x 0 x_3) →
      (∀ (x x_3 : ℕ), motive x x_3 0) → (∀ (n n_1 n_2 : ℕ), motive n.succ n_1.succ n_2.succ) → motive x x_1 x_2