proposition: Lemma orSys (T : System) (f g h : Formula) : SysPrf (Ensembles.Add _ T f) h -> SysPrf (Ensembles.Add _ T g) h -> SysPrf (Ensembles.Add _ T (f \/ g)%fol) h.
proof: Proof. apply (orSys LNN). Qed.
imports: Coq(Arith Ensembles List) LibHyps(LibHyps) hydras(MoreLibHyps NewNotations)