X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Flibrary%2Fnat%2Fnat.ma;h=b54bc76a9b4b416e80a35d5bb01b48fea9b70f5c;hb=6ff5322f46c2e88e07b4c345bc45edda7042128a;hp=b600072c61ba97cfa9e862251d04c566b3a0e765;hpb=7f2444c2670cadafddd8785b687ef312158376b0;p=helm.git

diff --git a/matita/library/nat/nat.ma b/matita/library/nat/nat.ma
index b600072c6..b54bc76a9 100644
--- a/matita/library/nat/nat.ma
+++ b/matita/library/nat/nat.ma
@@ -26,7 +26,7 @@ definition pred: nat \to nat \def
  | (S p) \Rightarrow p ].
 
 theorem pred_Sn : \forall n:nat.n=(pred (S n)).
- intros. reflexivity.
+ intros. simplify. reflexivity.
 qed.
 
 theorem injective_S : injective nat nat S.