X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fdelayed_updating%2Fsubstitution%2Flift_prototerm.ma;h=6555b5d9ed0ec36e6d6d1605a92cfe591e740a63;hb=85fcff9664b400a1cf25f383505638ffe34222b6;hp=4a0615a3ca081265e256e54a4cb683ef7810e351;hpb=538c84b5b1129b34c051c364fdd304f52714482c;p=helm.git

diff --git a/matita/matita/contribs/lambdadelta/delayed_updating/substitution/lift_prototerm.ma b/matita/matita/contribs/lambdadelta/delayed_updating/substitution/lift_prototerm.ma
index 4a0615a3c..6555b5d9e 100644
--- a/matita/matita/contribs/lambdadelta/delayed_updating/substitution/lift_prototerm.ma
+++ b/matita/matita/contribs/lambdadelta/delayed_updating/substitution/lift_prototerm.ma
@@ -14,7 +14,7 @@
 
 include "delayed_updating/substitution/lift.ma".
 include "delayed_updating/syntax/prototerm.ma".
-include "ground/lib/subset_ext_equivalence.ma".
+include "ground/lib/subset_ext.ma".
 
 (* LIFT FOR PROTOTERM *******************************************************)
 
@@ -28,8 +28,3 @@ lemma in_comp_lift_bi (f) (p) (t):
       p ϵ t → ↑[f]p ϵ ↑[f]t.
 /2 width=1 by subset_in_ext_f1_dx/
 qed.
-
-lemma eq_lift_bi (f) (t1) (t2):
-      t1 ⇔ t2 → ↑[f]t1 ⇔ ↑[f]t2.
-/2 width=1 by subset_equivalence_ext_f1_bi/
-qed.