proposition: Lemma phi0_lt_epsilon0_R (alpha : Ord): phi0 alpha < epsilon0 -> alpha < epsilon0.
proof: Proof. intro H; rewrite <- epsilon0_fxp in H; now apply phi0_mono_R. Qed.
imports: Coq(Arith Logic.Epsilon Ensembles Lia) ZornsLemma(CountableTypes)