xboolean.miz
    
    begin
    
    definition
    
      :: 
    
    XBOOLEAN:def1
    
      func
    
    FALSE -> 
    object equals 
    0 ; 
    
      coherence ;
    
      :: 
    
    XBOOLEAN:def2
    
      func
    
    TRUE -> 
    object equals 1; 
    
      coherence ;
    
    end
    
    definition
    
      let p be
    object;
    
      :: 
    
    XBOOLEAN:def3
    
      attr p is
    
    boolean means 
    
      :
    
    Def3: p 
    =  
    FALSE or p 
    =  
    TRUE ; 
    
    end
    
    registration
    
      cluster 
    FALSE -> 
    boolean;
    
      coherence ;
    
      cluster 
    TRUE -> 
    boolean;
    
      coherence ;
    
      cluster 
    boolean for 
    object;
    
      existence by
    Def3;
    
      cluster 
    boolean -> 
    natural for 
    object;
    
      coherence ;
    
    end
    
    reserve p,q,r,s for
    boolean  
    object;
    
    definition
    
      let p;
    
      :: 
    
    XBOOLEAN:def4
    
      func
    
    'not' p -> 
    boolean  
    object equals (1 
    - p); 
    
      coherence
    
      proof
    
        p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
        hence thesis by
    Def3;
    
      end;
    
      involutiveness ;
    
      let q;
    
      :: 
    
    XBOOLEAN:def5
    
      func p
    
    '&' q -> 
    object equals (p 
    * q); 
    
      correctness ;
    
      commutativity ;
    
      idempotence
    
      proof
    
        let p;
    
        p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
        hence thesis;
    
      end;
    
    end
    
    registration
    
      let p, q;
    
      cluster (p 
    '&' q) -> 
    boolean;
    
      coherence
    
      proof
    
        p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
        hence thesis;
    
      end;
    
    end
    
    definition
    
      let p, q;
    
      :: 
    
    XBOOLEAN:def6
    
      func p
    
    'or' q -> 
    object equals ( 
    'not' (( 
    'not' p) 
    '&' ( 
    'not' q))); 
    
      coherence ;
    
      commutativity ;
    
      idempotence ;
    
    end
    
    definition
    
      let p, q;
    
      :: 
    
    XBOOLEAN:def7
    
      func p
    
    => q -> 
    object equals (( 
    'not' p) 
    'or' q); 
    
      coherence ;
    
    end
    
    registration
    
      let p, q;
    
      cluster (p 
    'or' q) -> 
    boolean;
    
      coherence ;
    
      cluster (p 
    => q) -> 
    boolean;
    
      coherence ;
    
    end
    
    definition
    
      let p, q;
    
      :: 
    
    XBOOLEAN:def8
    
      func p
    
    <=> q -> 
    object equals ((p 
    => q) 
    '&' (q 
    => p)); 
    
      coherence ;
    
      commutativity ;
    
    end
    
    registration
    
      let p, q;
    
      cluster (p 
    <=> q) -> 
    boolean;
    
      coherence ;
    
    end
    
    definition
    
      let p, q;
    
      :: 
    
    XBOOLEAN:def9
    
      func p
    
    'nand' q -> 
    object equals ( 
    'not' (p 
    '&' q)); 
    
      coherence ;
    
      commutativity ;
    
      :: 
    
    XBOOLEAN:def10
    
      func p
    
    'nor' q -> 
    object equals ( 
    'not' (p 
    'or' q)); 
    
      coherence ;
    
      commutativity ;
    
      :: 
    
    XBOOLEAN:def11
    
      func p
    
    'xor' q -> 
    object equals ( 
    'not' (p 
    <=> q)); 
    
      coherence ;
    
      commutativity ;
    
      :: 
    
    XBOOLEAN:def12
    
      func p
    
    '\' q -> 
    object equals (p 
    '&' ( 
    'not' q)); 
    
      coherence ;
    
    end
    
    registration
    
      let p, q;
    
      cluster (p 
    'nand' q) -> 
    boolean;
    
      coherence ;
    
      cluster (p 
    'nor' q) -> 
    boolean;
    
      coherence ;
    
      cluster (p 
    'xor' q) -> 
    boolean;
    
      coherence ;
    
      cluster (p 
    '\' q) -> 
    boolean;
    
      coherence ;
    
    end
    
    begin
    
    theorem :: 
    
    XBOOLEAN:1
    
    (p
    '&' p) 
    = p; 
    
    theorem :: 
    
    XBOOLEAN:2
    
    (p
    '&' (p 
    '&' q)) 
    = (p 
    '&' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:3
    
    (p
    'or' p) 
    = p; 
    
    theorem :: 
    
    XBOOLEAN:4
    
    (p
    'or' (p 
    'or' q)) 
    = (p 
    'or' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:5
    
    (p
    'or' (p 
    '&' q)) 
    = p 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:6
    
    (p
    '&' (p 
    'or' q)) 
    = p 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:7
    
    (p
    '&' (p 
    'or' q)) 
    = (p 
    'or' (p 
    '&' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:8
    
    (p
    '&' (q 
    'or' r)) 
    = ((p 
    '&' q) 
    'or' (p 
    '&' r)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:9
    
    (p
    'or' (q 
    '&' r)) 
    = ((p 
    'or' q) 
    '&' (p 
    'or' r)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:10
    
    (((p
    '&' q) 
    'or' (q 
    '&' r)) 
    'or' (r 
    '&' p)) 
    = (((p 
    'or' q) 
    '&' (q 
    'or' r)) 
    '&' (r 
    'or' p)) 
    
    proof
    
      
    
      
    
    A1: q 
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis by
    A1;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:11
    
    (p
    '&' (( 
    'not' p) 
    'or' q)) 
    = (p 
    '&' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:12
    
    (p
    'or' (( 
    'not' p) 
    '&' q)) 
    = (p 
    'or' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:13
    
    (p
    => (p 
    => q)) 
    = (p 
    => q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:14
    
    (p
    '&' (p 
    => q)) 
    = (p 
    '&' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:15
    
    (p
    => (p 
    '&' q)) 
    = (p 
    => q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:16
    
    (p
    '&' ( 
    'not' (p 
    => q))) 
    = (p 
    '&' ( 
    'not' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:17
    
    ((
    'not' p) 
    'or' (p 
    => q)) 
    = (p 
    => q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:18
    
    ((
    'not' p) 
    '&' (p 
    => q)) 
    = (( 
    'not' p) 
    'or' (( 
    'not' p) 
    '&' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:19
    
    ((p
    <=> q) 
    <=> r) 
    = (p 
    <=> (q 
    <=> r)) 
    
    proof
    
      q
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:20
    
    (p
    '&' (p 
    <=> q)) 
    = (p 
    '&' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:21
    
    ((
    'not' p) 
    '&' (p 
    <=> q)) 
    = (( 
    'not' p) 
    '&' ( 
    'not' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:22
    
    (p
    '&' (q 
    <=> r)) 
    = ((p 
    '&' (( 
    'not' q) 
    'or' r)) 
    '&' (( 
    'not' r) 
    'or' q)); 
    
    theorem :: 
    
    XBOOLEAN:23
    
    (p
    'or' (q 
    <=> r)) 
    = (((p 
    'or' ( 
    'not' q)) 
    'or' r) 
    '&' ((p 
    'or' ( 
    'not' r)) 
    'or' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:24
    
    ((
    'not' p) 
    '&' (p 
    <=> q)) 
    = ((( 
    'not' p) 
    '&' ( 
    'not' q)) 
    '&' (( 
    'not' p) 
    'or' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:25
    
    ((
    'not' p) 
    '&' (q 
    <=> r)) 
    = ((( 
    'not' p) 
    '&' (( 
    'not' q) 
    'or' r)) 
    '&' (( 
    'not' r) 
    'or' q)); 
    
    theorem :: 
    
    XBOOLEAN:26
    
    (p
    => (p 
    <=> q)) 
    = (p 
    => q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:27
    
    (p
    => (p 
    <=> q)) 
    = (p 
    => (p 
    => q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:28
    
    (p
    'or' (p 
    <=> q)) 
    = (q 
    => p) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:29
    
    ((
    'not' p) 
    'or' (p 
    <=> q)) 
    = (p 
    => q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:30
    
    (p
    => (q 
    <=> r)) 
    = (((( 
    'not' p) 
    'or' ( 
    'not' q)) 
    'or' r) 
    '&' ((( 
    'not' p) 
    'or' q) 
    'or' ( 
    'not' r))) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:31
    
    (p
    'nor' p) 
    = ( 
    'not' p); 
    
    theorem :: 
    
    XBOOLEAN:32
    
    (p
    'nor' (p 
    '&' q)) 
    = ( 
    'not' p) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:33
    
    (p
    'nor' (p 
    'or' q)) 
    = (( 
    'not' p) 
    '&' ( 
    'not' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:34
    
    (p
    'nor' (p 
    'nor' q)) 
    = (( 
    'not' p) 
    '&' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:35
    
    (p
    'nor' (p 
    '&' q)) 
    = ( 
    'not' p) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:36
    
    (p
    'nor' (p 
    'or' q)) 
    = (p 
    'nor' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:37
    
    ((
    'not' p) 
    '&' (p 
    'nor' q)) 
    = (p 
    'nor' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:38
    
    (p
    'or' (q 
    'nor' r)) 
    = ((p 
    'or' ( 
    'not' q)) 
    '&' (p 
    'or' ( 
    'not' r))) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:39
    
    (p
    'nor' (q 
    'nor' r)) 
    = ((( 
    'not' p) 
    '&' q) 
    'or' (( 
    'not' p) 
    '&' r)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:40
    
    (p
    'nor' (q 
    '&' r)) 
    = (( 
    'not' (p 
    'or' q)) 
    'or' ( 
    'not' (p 
    'or' r))) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:41
    
    (p
    '&' (q 
    'nor' r)) 
    = ((p 
    '&' ( 
    'not' q)) 
    '&' ( 
    'not' r)) 
    
    proof
    
      
    
      thus (p
    '&' (q 
    'nor' r)) 
    = (p 
    '&' (( 
    'not' q) 
    '&' ( 
    'not' r))) 
    
      .= ((p
    '&' ( 
    'not' q)) 
    '&' ( 
    'not' r)); 
    
    end;
    
    theorem :: 
    
    XBOOLEAN:42
    
    (p
    => (p 
    'nor' q)) 
    = ( 
    'not' p) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:43
    
    (p
    => (q 
    'nor' r)) 
    = ((p 
    => ( 
    'not' q)) 
    '&' (p 
    => ( 
    'not' r))) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:44
    
    (p
    'or' (p 
    'nor' q)) 
    = (q 
    => p) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:45
    
    (p
    'or' (q 
    'nor' r)) 
    = ((q 
    => p) 
    '&' (r 
    => p)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:46
    
    (p
    => (q 
    'nor' r)) 
    = ((( 
    'not' p) 
    'or' ( 
    'not' q)) 
    '&' (( 
    'not' p) 
    'or' ( 
    'not' r))) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:47
    
    (p
    'nor' (p 
    <=> q)) 
    = (( 
    'not' p) 
    '&' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:48
    
    ((
    'not' p) 
    '&' (p 
    <=> q)) 
    = (p 
    'nor' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:49
    
    (p
    'nor' (q 
    <=> r)) 
    = ( 
    'not' (((p 
    'or' ( 
    'not' q)) 
    'or' r) 
    '&' ((p 
    'or' ( 
    'not' r)) 
    'or' q))) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:50
    
    (p
    <=> q) 
    = ((p 
    '&' q) 
    'or' (p 
    'nor' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:51
    
    (p
    'nand' p) 
    = ( 
    'not' p); 
    
    theorem :: 
    
    XBOOLEAN:52
    
    (p
    '&' (p 
    'nand' q)) 
    = (p 
    '&' ( 
    'not' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:53
    
    (p
    'nand' (p 
    '&' q)) 
    = ( 
    'not' (p 
    '&' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:54
    
    (p
    'nand' (q 
    'nand' r)) 
    = ((( 
    'not' p) 
    'or' q) 
    '&' (( 
    'not' p) 
    'or' r)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:55
    
    (p
    'nand' (q 
    'or' r)) 
    = (( 
    'not' (p 
    '&' q)) 
    '&' ( 
    'not' (p 
    '&' r))) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:56
    
    (p
    => (p 
    'nand' q)) 
    = (p 
    'nand' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:57
    
    (p
    'nand' (p 
    'nand' q)) 
    = (p 
    => q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:58
    
    (p
    'nand' (q 
    'nand' r)) 
    = ((p 
    => q) 
    '&' (p 
    => r)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:59
    
    (p
    'nand' (p 
    => q)) 
    = ( 
    'not' (p 
    '&' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:60
    
    (p
    'nand' (q 
    => r)) 
    = ((p 
    => q) 
    '&' (p 
    => ( 
    'not' r))) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:61
    
    ((
    'not' p) 
    'or' (p 
    'nand' q)) 
    = (p 
    'nand' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:62
    
    (p
    'nand' (q 
    => r)) 
    = ((( 
    'not' p) 
    'or' q) 
    '&' (( 
    'not' p) 
    'or' ( 
    'not' r))) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:63
    
    ((
    'not' p) 
    '&' (p 
    'nand' q)) 
    = (( 
    'not' p) 
    'or' (( 
    'not' p) 
    '&' ( 
    'not' q))) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:64
    
    (p
    '&' (q 
    'nand' r)) 
    = ((p 
    '&' ( 
    'not' q)) 
    'or' (p 
    '&' ( 
    'not' r))) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:65
    
    (p
    'nand' (p 
    <=> q)) 
    = ( 
    'not' (p 
    '&' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:66
    
    (p
    'nand' (q 
    <=> r)) 
    = ( 
    'not' ((p 
    '&' (( 
    'not' q) 
    'or' r)) 
    '&' (( 
    'not' r) 
    'or' q))); 
    
    theorem :: 
    
    XBOOLEAN:67
    
    (p
    'nand' (q 
    'nor' r)) 
    = ((( 
    'not' p) 
    'or' q) 
    'or' r) 
    
    proof
    
      
    
      thus (p
    'nand' (q 
    'nor' r)) 
    = (( 
    'not' p) 
    'or' (q 
    'or' r)) 
    
      .= (((
    'not' p) 
    'or' q) 
    'or' r); 
    
    end;
    
    theorem :: 
    
    XBOOLEAN:68
    
    ((p
    '\' q) 
    '\' q) 
    = (p 
    '\' q) 
    
    proof
    
      q
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:69
    
    (p
    '&' (p 
    '\' q)) 
    = (p 
    '\' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:70
    
    (p
    'nor' (p 
    <=> q)) 
    = (q 
    '\' p) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:71
    
    (p
    'nor' (p 
    'nor' q)) 
    = (q 
    '\' p) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:72
    
    (p
    'xor' (p 
    'xor' q)) 
    = q 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:73
    
    ((p
    'xor' q) 
    'xor' r) 
    = (p 
    'xor' (q 
    'xor' r)) 
    
    proof
    
      q
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:74
    
    (
    'not' (p 
    'xor' q)) 
    = (( 
    'not' p) 
    'xor' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:75
    
    (p
    '&' (q 
    'xor' r)) 
    = ((p 
    '&' q) 
    'xor' (p 
    '&' r)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:76
    
    (p
    '&' (p 
    'xor' q)) 
    = (p 
    '&' ( 
    'not' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:77
    
    (p
    'xor' (p 
    '&' q)) 
    = (p 
    '&' ( 
    'not' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:78
    
    ((
    'not' p) 
    '&' (p 
    'xor' q)) 
    = (( 
    'not' p) 
    '&' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:79
    
    (p
    'or' (p 
    'xor' q)) 
    = (p 
    'or' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:80
    
    (p
    'or' (( 
    'not' p) 
    'xor' q)) 
    = (p 
    'or' ( 
    'not' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:81
    
    (p
    'xor' (( 
    'not' p) 
    '&' q)) 
    = (p 
    'or' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:82
    
    (p
    'xor' (p 
    'or' q)) 
    = (( 
    'not' p) 
    '&' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:83
    
    (p
    'xor' (q 
    '&' r)) 
    = ((p 
    'or' (q 
    '&' r)) 
    '&' (( 
    'not' p) 
    'or' ( 
    'not' (q 
    '&' r)))) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:84
    
    ((
    'not' p) 
    'xor' (p 
    => q)) 
    = (p 
    '&' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:85
    
    (p
    => (p 
    'xor' q)) 
    = (( 
    'not' p) 
    'or' ( 
    'not' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:86
    
    (p
    'xor' (p 
    => q)) 
    = (( 
    'not' p) 
    'or' ( 
    'not' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:87
    
    ((
    'not' p) 
    'xor' (q 
    => p)) 
    = ((p 
    '&' (p 
    'or' ( 
    'not' q))) 
    'or' (( 
    'not' p) 
    '&' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:88
    
    (p
    'xor' (p 
    <=> q)) 
    = ( 
    'not' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:89
    
    ((
    'not' p) 
    'xor' (p 
    <=> q)) 
    = q 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:90
    
    (p
    'nor' (p 
    'xor' q)) 
    = (( 
    'not' p) 
    '&' ( 
    'not' q)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:91
    
    (p
    'nor' (p 
    'xor' q)) 
    = (p 
    'nor' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:92
    
    (p
    'xor' (p 
    'nor' q)) 
    = (q 
    => p) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:93
    
    (p
    'nand' (p 
    'xor' q)) 
    = (p 
    => q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:94
    
    (p
    'xor' (p 
    'nand' q)) 
    = (p 
    => q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:95
    
    (p
    'xor' (p 
    => q)) 
    = (p 
    'nand' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:96
    
    (p
    'nand' (q 
    'xor' r)) 
    = ((p 
    '&' q) 
    <=> (p 
    '&' r)) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:97
    
    (p
    'xor' (p 
    '&' q)) 
    = (p 
    '\' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:98
    
    (p
    '&' (p 
    'xor' q)) 
    = (p 
    '\' q) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:99
    
    ((
    'not' p) 
    '&' (p 
    'xor' q)) 
    = (q 
    '\' p) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:100
    
    (p
    'xor' (p 
    'or' q)) 
    = (q 
    '\' p) 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    begin
    
    theorem :: 
    
    XBOOLEAN:101
    
    (p
    '&' q) 
    =  
    TRUE implies p 
    =  
    TRUE & q 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:102
    
    (
    'not' (p 
    '&' ( 
    'not' p))) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:103
    
    (p
    => p) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:104
    
    (p
    => (q 
    => p)) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:105
    
    (p
    => ((p 
    => q) 
    => q)) 
    =  
    TRUE  
    
    proof
    
      
    
      
    
    A1: q 
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis by
    A1;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:106
    
    ((p
    => q) 
    => ((q 
    => r) 
    => (p 
    => r))) 
    =  
    TRUE  
    
    proof
    
      
    
      
    
    A1: q 
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      
    
      
    
    A2: p 
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      r
    =  
    FALSE or r 
    =  
    TRUE by 
    Def3;
    
      hence thesis by
    A1,
    A2;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:107
    
    ((p
    => q) 
    => ((r 
    => p) 
    => (r 
    => q))) 
    =  
    TRUE  
    
    proof
    
      
    
      
    
    A1: q 
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      
    
      
    
    A2: p 
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      r
    =  
    FALSE or r 
    =  
    TRUE by 
    Def3;
    
      hence thesis by
    A1,
    A2;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:108
    
    ((p
    => (p 
    => q)) 
    => (p 
    => q)) 
    =  
    TRUE  
    
    proof
    
      
    
      
    
    A1: q 
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis by
    A1;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:109
    
    ((p
    => (q 
    => r)) 
    => ((p 
    => q) 
    => (p 
    => r))) 
    =  
    TRUE  
    
    proof
    
      
    
      
    
    A1: q 
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      
    
      
    
    A2: p 
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      r
    =  
    FALSE or r 
    =  
    TRUE by 
    Def3;
    
      hence thesis by
    A1,
    A2;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:110
    
    ((p
    => (q 
    => r)) 
    => (q 
    => (p 
    => r))) 
    =  
    TRUE  
    
    proof
    
      
    
      
    
    A1: q 
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      
    
      
    
    A2: p 
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      r
    =  
    FALSE or r 
    =  
    TRUE by 
    Def3;
    
      hence thesis by
    A1,
    A2;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:111
    
    (((p
    => q) 
    => r) 
    => (q 
    => r)) 
    =  
    TRUE  
    
    proof
    
      
    
      
    
    A1: q 
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      r
    =  
    FALSE or r 
    =  
    TRUE by 
    Def3;
    
      hence thesis by
    A1;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:112
    
    ((
    TRUE  
    => p) 
    => p) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:113
    
    (p
    => q) 
    =  
    TRUE implies ((q 
    => r) 
    => (p 
    => r)) 
    =  
    TRUE  
    
    proof
    
      r
    =  
    FALSE or r 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:114
    
    (p
    => (p 
    => q)) 
    =  
    TRUE implies (p 
    => q) 
    =  
    TRUE  
    
    proof
    
      q
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:115
    
    (p
    => (q 
    => r)) 
    =  
    TRUE implies ((p 
    => q) 
    => (p 
    => r)) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:116
    
    (p
    => q) 
    =  
    TRUE & (q 
    => p) 
    =  
    TRUE implies p 
    = q 
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:117
    
    (p
    => q) 
    =  
    TRUE & (q 
    => r) 
    =  
    TRUE implies (p 
    => r) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:118
    
    (((
    'not' p) 
    => p) 
    => p) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:119
    
    (
    'not' p) 
    =  
    TRUE implies (p 
    => q) 
    =  
    TRUE ; 
    
    theorem :: 
    
    XBOOLEAN:120
    
    (p
    => q) 
    =  
    TRUE & (p 
    => ( 
    'not' q)) 
    =  
    TRUE implies ( 
    'not' p) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:121
    
    ((p
    => q) 
    => (( 
    'not' (q 
    '&' r)) 
    => ( 
    'not' (p 
    '&' r)))) 
    =  
    TRUE  
    
    proof
    
      
    
      
    
    A1: q 
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      
    
      
    
    A2: p 
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      r
    =  
    FALSE or r 
    =  
    TRUE by 
    Def3;
    
      hence thesis by
    A1,
    A2;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:122
    
    (p
    'or' (p 
    => q)) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:123
    
    (p
    => (p 
    'or' q)) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:124
    
    ((
    'not' q) 
    'or' ((q 
    => p) 
    => p)) 
    =  
    TRUE  
    
    proof
    
      
    
      
    
    A1: q 
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis by
    A1;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:125
    
    (p
    <=> p) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:126
    
    ((((p
    <=> q) 
    <=> r) 
    <=> p) 
    <=> (q 
    <=> r)) 
    =  
    TRUE  
    
    proof
    
      
    
      
    
    A1: q 
    =  
    FALSE or q 
    =  
    TRUE by 
    Def3;
    
      
    
      
    
    A2: p 
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      r
    =  
    FALSE or r 
    =  
    TRUE by 
    Def3;
    
      hence thesis by
    A1,
    A2;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:127
    
    (p
    <=> q) 
    =  
    TRUE & (q 
    <=> r) 
    =  
    TRUE implies (p 
    <=> r) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:128
    
    (p
    <=> q) 
    =  
    TRUE & (r 
    <=> s) 
    =  
    TRUE implies ((p 
    <=> r) 
    <=> (q 
    <=> s)) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:129
    
    (
    'not' (p 
    <=> ( 
    'not' p))) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:130
    
    (p
    <=> q) 
    =  
    TRUE & (r 
    <=> s) 
    =  
    TRUE implies ((p 
    '&' r) 
    <=> (q 
    '&' s)) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:131
    
    (p
    <=> q) 
    =  
    TRUE & (r 
    <=> s) 
    =  
    TRUE implies ((p 
    'or' r) 
    <=> (q 
    'or' s)) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:132
    
    (p
    <=> q) 
    =  
    TRUE iff (p 
    => q) 
    =  
    TRUE & (q 
    => p) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:133
    
    (p
    <=> q) 
    =  
    TRUE & (r 
    <=> s) 
    =  
    TRUE implies ((p 
    => r) 
    <=> (q 
    => s)) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:134
    
    (
    'not' (p 
    'nor' ( 
    'not' p))) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:135
    
    (p
    'nand' ( 
    'not' p)) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:136
    
    (p
    'or' (p 
    'nand' q)) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:137
    
    (p
    'nand' (p 
    'nor' q)) 
    =  
    TRUE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:138
    
    (p
    '&' ( 
    'not' p)) 
    =  
    FALSE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:139
    
    (p
    '&' p) 
    =  
    FALSE implies p 
    =  
    FALSE ; 
    
    theorem :: 
    
    XBOOLEAN:140
    
    (p
    '&' q) 
    =  
    FALSE implies p 
    =  
    FALSE or q 
    =  
    FALSE ; 
    
    theorem :: 
    
    XBOOLEAN:141
    
    (
    'not' (p 
    => p)) 
    =  
    FALSE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:142
    
    (p
    <=> ( 
    'not' p)) 
    =  
    FALSE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:143
    
    (
    'not' (p 
    <=> p)) 
    =  
    FALSE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:144
    
    (p
    '&' (p 
    'nor' q)) 
    =  
    FALSE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:145
    
    (p
    'nor' (p 
    => q)) 
    =  
    FALSE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:146
    
    (p
    'nor' (p 
    'nand' q)) 
    =  
    FALSE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;
    
    theorem :: 
    
    XBOOLEAN:147
    
    (p
    'xor' p) 
    =  
    FALSE  
    
    proof
    
      p
    =  
    FALSE or p 
    =  
    TRUE by 
    Def3;
    
      hence thesis;
    
    end;