X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fmatita%2Fnlibrary%2FPlogic%2Fconnectives.ma;h=491657676a85ada0ae073947190306fedbb0af87;hb=e91eb82d2b5e032907758bff0b474d62d57463dc;hp=84bd36454064e90ba35f74df324a28cb8407f83f;hpb=ee1df68d10351f30ea591ccc2173197d99e307cc;p=helm.git

diff --git a/helm/software/matita/nlibrary/Plogic/connectives.ma b/helm/software/matita/nlibrary/Plogic/connectives.ma
index 84bd36454..491657676 100644
--- a/helm/software/matita/nlibrary/Plogic/connectives.ma
+++ b/helm/software/matita/nlibrary/Plogic/connectives.ma
@@ -30,8 +30,6 @@ ndefinition Not: Prop → Prop ≝
 ninductive Not (A:Prop): Prop ≝
 nmk: (A → False) → Not A.
 
-ncheck Not_ind.
-
 interpretation "logical not" 'not x = (Not x).
 
 ntheorem absurd : ∀ A:Prop. A → ¬A → False.