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