∀ {α : Type u_1} [inst : AddCommGroup α] (val : Fintype α)
  (motive : (∃ a ∈ Finset.univ, addOrderOf a = (Finset.image addOrderOf Finset.univ).max' ⋯) → Prop)
  (x : ∃ a ∈ Finset.univ, addOrderOf a = (Finset.image addOrderOf Finset.univ).max' ⋯),
  (∀ (g : α) (left : g ∈ Finset.univ) (hg : addOrderOf g = (Finset.image addOrderOf Finset.univ).max' ⋯), motive ⋯) →
    motive x