--- a/progs/prove.scala	Tue Nov 12 14:40:46 2013 +0000
+++ b/progs/prove.scala	Tue Nov 12 21:13:00 2013 +0000
@@ -118,7 +118,7 @@
 
 val Chr = "Christian"
 val HoD = "Peter"
-val Email = Pred("may_btain_email", List(Const(Chr)))
+val Email = Pred("may_obtain_email", List(Const(Chr)))
 val AtLib = Pred("is_at_library", List(Const(Chr)))
 val Chr_Staff = Pred("is_staff", List(Const(Chr)))
 
@@ -126,6 +126,6 @@
 val Policy_Lib = And(Chr_Staff, AtLib) -> Email
 val HoD_says = HoD says Chr_Staff
 
-run (Set[Form](AtLib, Policy_HoD, Policy_Lib, HoD_says) |- Email)
+run (Set[Form](AtLib, Policy_HoD, Policy_Lib) |- Email)