∀ (K : Type u_2) (K' : Type u_1) [inst : Field K] [inst_1 : Field K'] [inst_2 : Algebra K K'] (k : K) (ne : k ≠ 0)
  (motive : (∃ a, (Units.map (Algebra.norm K)) a = Units.mk0 k ne) → Prop)
  (x : ∃ a, (Units.map (Algebra.norm K)) a = Units.mk0 k ne),
  (∀ (x : K'ˣ) (eq : (Units.map (Algebra.norm K)) x = Units.mk0 k ne), motive ⋯) → motive x