∀ {ι : Type u_1} {β : ι → Type u_2} [inst : LinearOrder ι] {x : (i : ι) → β i} {i : ι} {a : β i}
  [inst_1 : (i : ι) → PartialOrder (β i)] [WellFoundedLT ι], (toLex x ≤ toLex (Function.update x i a)) = (x i ≤ a)