X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fcontribs%2FRELATIONAL-ARITHMETICS%2Fnat_defs.ma;h=30d6cfb5ca1ae1e7dd4dcaafa2c8489f1ef1e89b;hb=9ed9bdd5f158f092114c2d98c2537a9396d6a8d7;hp=9b8ab4571ea42dab918013b786717e9fe22d6893;hpb=a5e886d4114b6c120406573f915572d0a38c8c01;p=helm.git

diff --git a/matita/contribs/RELATIONAL-ARITHMETICS/nat_defs.ma b/matita/contribs/RELATIONAL-ARITHMETICS/nat_defs.ma
index 9b8ab4571..30d6cfb5c 100644
--- a/matita/contribs/RELATIONAL-ARITHMETICS/nat_defs.ma
+++ b/matita/contribs/RELATIONAL-ARITHMETICS/nat_defs.ma
@@ -14,6 +14,8 @@
 
 set "baseuri" "cic:/matita/RELATIONAL-ARITHMETICS/nat_defs".
 
+include "logic/equality.ma".
+
 inductive nat: Set \def
    | O: nat
    | S: nat \to nat.