proposition: Lemma Equalizer_iso : forall (h1 : a --> E_ob f) (p : RIso_law (E_mor f) h1), let f1 := E_diese f (Epic_Equalizer_id (RightInv_epic p)) in AreIsos (E_mor f) f1.
proof: Proof. intros h1 ri; simpl in |- *; apply Epic_Equalizer_iso. Qed.
imports: CatProperty