-lemma cnx_inv_abbr_pos (h) (o) (G) (L): ∀V,T. ⦃G,L⦄ ⊢ ⬈[h,o] 𝐍⦃+ⓓV.T⦄ → ⊥.
-#h #o #G #L #V #U1 #H
-elim (cpx_subst h G (L.ⓓV) U1 … 0) [|*: /2 width=4 by drops_refl/ ] #U2 #T2 #HU12 #HTU2
-elim (tdeq_dec h o U1 U2) #HnU12 [ -HU12 | -HTU2 ]
-[ elim (tdeq_inv_lifts_dx … HnU12 … HTU2) -U2 #T1 #HTU1 #_ -T2
+lemma cnx_inv_abbr_pos (G) (L):
+ ∀V,T. ❪G,L❫ ⊢ ⬈𝐍 +ⓓV.T → ⊥.
+#G #L #V #U1 #H
+elim (cpx_subst G (L.ⓓV) U1 … 0) [|*: /2 width=4 by drops_refl/ ] #U2 #T2 #HU12 #HTU2
+elim (teqx_dec U1 U2) #HnU12 [ -HU12 | -HTU2 ]
+[ elim (teqx_inv_lifts_dx … HnU12 … HTU2) -U2 #T1 #HTU1 #_ -T2