matita/matita/contribs/lambdadelta/ground_2/lib/logic.ma

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   3 (*      ||M||                                                             *)
   4 (*      ||A||       A project by Andrea Asperti                           *)
   5 (*      ||T||                                                             *)
   6 (*      ||I||       Developers:                                           *)
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  10 (*       \ /        This file is distributed under the terms of the       *)
  11 (*        v         GNU General Public License Version 2                  *)
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  13 (**************************************************************************)
  14
  15 include "basics/logic.ma".
  16 include "ground_2/notation/xoa/false_0.ma".
  17 include "ground_2/notation/xoa/true_0.ma".
  18 include "ground_2/notation/xoa/or_2.ma".
  19 include "ground_2/notation/xoa/and_2.ma".
  20 include "ground_2/xoa/xoa.ma".
  21
  22 interpretation "logical false" 'false = False.
  23
  24 interpretation "logical true" 'true = True.
  25
  26 (* Logical properties missing in the basic library **************************)
  27
  28 lemma commutative_and: ∀A,B. A ∧ B → B ∧ A.
  29 #A #B * /2 width=1 by conj/
  30 qed-.