proposition: Lemma FT_eq_tau : forall i : FT_I, FT_tau i =_S FT_tau_d o FMor G (FT_Apeps i).
proof: Proof. intro i; apply Sym; apply (Prf_limit1 L_X FT_tau i). Qed.
imports: FSC_inc Comma_proj FAFT_SSC2 Th_Adjoint Pres_Limits Pullbacks1