helm/matita/tests/absurd.ma

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  14
  15 set "baseuri" "cic:/matita/tests/absurd/".
  16 alias num (instance 0) = "natural number".
  17 alias symbol "eq" (instance 0) = "leibnitz's equality".
  18 alias id "not" = "cic:/Coq/Init/Logic/not.con".
  19
  20
  21
  22 theorem stupid : \forall a:Prop. a \to not a \to 0 = 1.
  23 intros.
  24 absurd a.
  25 assumption.
  26 assumption.
  27 qed.