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Theorem List for Metamath Proof Explorer - 34101-34200   *Has distinct variable group(s)
TypeLabelDescription
Statement
 
Theoremcdlemg6e 34101 TODO: FIX COMMENT. (Contributed by NM, 27-Apr-2013.)
 |-  .<_  =  ( le `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  (
 LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  .\/  =  ( join `  K )   &    |-  V  =  ( R `  G )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  (
 ( P  e.  A  /\  -.  P  .<_  W ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  F  e.  T )  /\  ( G  e.  T  /\  Q  .<_  ( P  .\/  V )  /\  ( F `  ( G `  P ) )  =  P ) )  ->  ( F `  ( G `  Q ) )  =  Q )
 
Theoremcdlemg6 34102 TODO: FIX COMMENT. (Contributed by NM, 27-Apr-2013.)
 |-  .<_  =  ( le `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  (
 LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  ( F `  ( G `  P ) )  =  P ) ) 
 ->  ( F `  ( G `  Q ) )  =  Q )
 
Theoremcdlemg7fvN 34103 Value of a translation composition in terms of an associated atom. (Contributed by NM, 28-Apr-2013.) (New usage is discouraged.)
 |-  B  =  ( Base `  K )   &    |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( X  e.  B  /\  -.  X  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  ( P  .\/  ( X  ./\  W ) )  =  X ) ) 
 ->  ( F `  ( G `  X ) )  =  ( ( F `
  ( G `  P ) )  .\/  ( X  ./\  W ) ) )
 
Theoremcdlemg7aN 34104 TODO: FIX COMMENT. (Contributed by NM, 28-Apr-2013.) (New usage is discouraged.)
 |-  B  =  ( Base `  K )   &    |-  .<_  =  ( le `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  (
 LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( X  e.  B  /\  -.  X  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  ( F `  ( G `  P ) )  =  P ) ) 
 ->  ( F `  ( G `  X ) )  =  X )
 
Theoremcdlemg7N 34105 TODO: FIX COMMENT. (Contributed by NM, 28-Apr-2013.) (New usage is discouraged.)
 |-  B  =  ( Base `  K )   &    |-  .<_  =  ( le `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  (
 LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  X  e.  B )  /\  ( F  e.  T  /\  G  e.  T  /\  ( F `
  ( G `  P ) )  =  P ) )  ->  ( F `  ( G `
  X ) )  =  X )
 
Theoremcdlemg8a 34106 TODO: FIX COMMENT. (Contributed by NM, 29-Apr-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  ( F `  ( G `  P ) )  =  P ) ) 
 ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )
 )
 
Theoremcdlemg8b 34107 TODO: FIX COMMENT. (Contributed by NM, 29-Apr-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  F  e.  T )  /\  ( G  e.  T  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =  ( P  .\/  Q )  /\  ( F `  ( G `  P ) )  =/=  P ) )  ->  ( P  .\/  ( F `  ( G `  P ) ) )  =  ( P 
 .\/  Q ) )
 
Theoremcdlemg8c 34108 TODO: FIX COMMENT. (Contributed by NM, 29-Apr-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  F  e.  T )  /\  ( G  e.  T  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =  ( P  .\/  Q )  /\  ( F `  ( G `  P ) )  =/=  P ) )  ->  ( Q  .\/  ( F `  ( G `  Q ) ) )  =  ( P 
 .\/  Q ) )
 
Theoremcdlemg8d 34109 TODO: FIX COMMENT. (Contributed by NM, 29-Apr-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  F  e.  T )  /\  ( G  e.  T  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =  ( P  .\/  Q )  /\  ( F `  ( G `  P ) )  =/=  P ) )  ->  ( ( P  .\/  ( F `  ( G `  P ) ) )  ./\  W )  =  ( ( Q 
 .\/  ( F `  ( G `  Q ) ) )  ./\  W ) )
 
Theoremcdlemg8 34110 TODO: FIX COMMENT. (Contributed by NM, 29-Apr-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  F  e.  T )  /\  ( G  e.  T  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =  ( P  .\/  Q ) ) )  ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )
 )
 
Theoremcdlemg9a 34111 TODO: FIX COMMENT. (Contributed by NM, 1-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  U  =  ( ( P  .\/  Q )  ./\  W )   =>    |-  (
 ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) 
 /\  F  e.  T )  /\  ( G  e.  T  /\  P  =/=  Q  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q ) ) )  ->  ( ( P  .\/  U )  ./\  ( ( F `  ( G `  P ) )  .\/  U ) )  .<_  ( ( G `  P ) 
 .\/  U ) )
 
Theoremcdlemg9b 34112 The triples  <. P ,  ( F `  ( G `
 P ) ) ,  ( F `  P ) >. and  <. Q , 
( F `  ( G `  Q )
) ,  ( F `
 Q ) >. are centrally perspective. TODO: FIX COMMENT. (Contributed by NM, 1-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  F  e.  T )  /\  ( G  e.  T  /\  P  =/=  Q  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q ) ) )  ->  ( ( P  .\/  Q )  ./\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `
  Q ) ) ) )  .<_  ( ( G `  P ) 
 .\/  ( G `  Q ) ) )
 
Theoremcdlemg9 34113 The triples  <. P ,  ( F `  ( G `
 P ) ) ,  ( F `  P ) >. and  <. Q , 
( F `  ( G `  Q )
) ,  ( F `
 Q ) >. are axially perspective by dalaw 33363. Part of Lemma G of [Crawley] p. 116, last 2 lines. TODO: FIX COMMENT. (Contributed by NM, 1-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  F  e.  T )  /\  ( G  e.  T  /\  P  =/=  Q  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q ) ) )  ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  ( Q  .\/  ( F `  ( G `  Q ) ) ) )  .<_  ( ( ( ( F `  ( G `  P ) )  .\/  ( G `  P ) )  ./\  ( ( F `  ( G `  Q ) )  .\/  ( G `  Q ) ) ) 
 .\/  ( ( ( G `  P ) 
 .\/  P )  ./\  (
 ( G `  Q )  .\/  Q ) ) ) )
 
Theoremcdlemg10b 34114 TODO: FIX COMMENT. TODO: Can this be moved up as a stand-alone theorem in ltrn* area? (Contributed by NM, 4-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  F  e.  T )  ->  ( ( ( F `  P ) 
 .\/  ( F `  Q ) )  ./\  W )  =  ( ( P  .\/  Q )  ./\ 
 W ) )
 
Theoremcdlemg10bALTN 34115 TODO: FIX COMMENT. TODO: Can this be moved up as a stand-alone theorem in ltrn* area? TODO: Compare this proof to cdlemg2m 34083 and pick best, if moved to ltrn* area. (Contributed by NM, 4-May-2013.) (New usage is discouraged.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H  /\  F  e.  T )  /\  ( P  e.  A  /\  -.  P  .<_  W ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W ) )  ->  (
 ( ( F `  P )  .\/  ( F `
  Q ) ) 
 ./\  W )  =  ( ( P  .\/  Q )  ./\  W ) )
 
Theoremcdlemg11a 34116 TODO: FIX COMMENT. (Contributed by NM, 4-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q ) ) )  ->  ( F `  ( G `
  P ) )  =/=  P )
 
Theoremcdlemg11aq 34117 TODO: FIX COMMENT. TODO: can proof using this be restructured to use cdlemg11a 34116? (Contributed by NM, 4-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q ) ) )  ->  ( F `  ( G `
  Q ) )  =/=  Q )
 
Theoremcdlemg10c 34118 TODO: FIX COMMENT. TODO: Can this be moved up as a stand-alone theorem in trl* area? (Contributed by NM, 4-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T ) )  ->  ( ( R `  F ) 
 .<_  ( ( G `  P )  .\/  ( G `
  Q ) )  <-> 
 ( R `  F )  .<_  ( P  .\/  Q ) ) )
 
Theoremcdlemg10a 34119 TODO: FIX COMMENT. (Contributed by NM, 3-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( ( F `  ( G `
  P ) ) 
 .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q )  /\  -.  ( R `  F )  .<_  ( P  .\/  Q )  /\  -.  ( R `  G )  .<_  ( P  .\/  Q )
 ) )  ->  (
 ( P  .\/  ( F `  ( G `  P ) ) ) 
 ./\  ( Q  .\/  ( F `  ( G `
  Q ) ) ) )  .<_  ( ( R `  F ) 
 .\/  ( R `  G ) ) )
 
Theoremcdlemg10 34120 TODO: FIX COMMENT. (Contributed by NM, 4-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( ( F `  ( G `
  P ) ) 
 .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q )  /\  -.  ( R `  F )  .<_  ( P  .\/  Q )  /\  -.  ( R `  G )  .<_  ( P  .\/  Q )
 ) )  ->  (
 ( P  .\/  ( F `  ( G `  P ) ) ) 
 ./\  ( Q  .\/  ( F `  ( G `
  Q ) ) ) )  .<_  W )
 
Theoremcdlemg11b 34121 TODO: FIX COMMENT. (Contributed by NM, 5-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  Q  e.  A )  /\  ( G  e.  T  /\  P  =/=  Q  /\  -.  ( R `  G )  .<_  ( P  .\/  Q )
 ) )  ->  ( P  .\/  Q )  =/=  ( ( G `  P )  .\/  ( G `
  Q ) ) )
 
Theoremcdlemg12a 34122 TODO: FIX COMMENT. (Contributed by NM, 5-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  U  =  ( ( P  .\/  Q )  ./\  W )   =>    |-  (
 ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) 
 /\  F  e.  T )  /\  ( G  e.  T  /\  P  =/=  Q  /\  ( P  .\/  U )  =/=  ( ( G `
  P )  .\/  U ) ) )  ->  ( ( P  .\/  U )  ./\  ( ( G `  P )  .\/  U ) )  .<_  ( ( F `  ( G `
  P ) ) 
 .\/  U ) )
 
Theoremcdlemg12b 34123 The triples  <. P ,  ( F `  P ) ,  ( F `  ( G `  P ) ) >. and  <. Q , 
( F `  Q
) ,  ( F `
 ( G `  Q ) ) >. are centrally perspective. TODO: FIX COMMENT. (Contributed by NM, 5-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  F  e.  T )  /\  ( G  e.  T  /\  P  =/=  Q  /\  -.  ( R `  G )  .<_  ( P  .\/  Q ) ) )  ->  ( ( P  .\/  Q )  ./\  ( ( G `  P )  .\/  ( G `  Q ) ) )  .<_  ( ( F `  ( G `
  P ) ) 
 .\/  ( F `  ( G `  Q ) ) ) )
 
Theoremcdlemg12c 34124 The triples  <. P ,  ( F `  P ) ,  ( F `  ( G `  P ) ) >. and  <. Q , 
( F `  Q
) ,  ( F `
 ( G `  Q ) ) >. are axially perspective by dalaw 33363. TODO: FIX COMMENT. (Contributed by NM, 5-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  F  e.  T )  /\  ( G  e.  T  /\  P  =/=  Q  /\  -.  ( R `  G )  .<_  ( P  .\/  Q ) ) )  ->  ( ( P  .\/  ( G `  P ) )  ./\  ( Q  .\/  ( G `  Q ) ) )  .<_  ( ( ( ( G `
  P )  .\/  ( F `  ( G `
  P ) ) )  ./\  ( ( G `  Q )  .\/  ( F `  ( G `
  Q ) ) ) )  .\/  (
 ( ( F `  ( G `  P ) )  .\/  P )  ./\  ( ( F `  ( G `  Q ) )  .\/  Q )
 ) ) )
 
Theoremcdlemg12d 34125 TODO: FIX COMMENT. (Contributed by NM, 5-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T )  /\  ( P  =/=  Q 
 /\  -.  ( R `  F )  .<_  ( P 
 .\/  Q )  /\  -.  ( R `  G ) 
 .<_  ( P  .\/  Q ) ) )  ->  ( R `  G ) 
 .<_  ( ( R `  F )  .\/  ( ( ( F `  ( G `  P ) ) 
 .\/  P )  ./\  (
 ( F `  ( G `  Q ) ) 
 .\/  Q ) ) ) )
 
Theoremcdlemg12e 34126 TODO: FIX COMMENT. (Contributed by NM, 6-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  .0.  =  ( 0. `  K )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( P  e.  A  /\  -.  P  .<_  W ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W ) )  /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q )  /\  ( -.  ( R `  F )  .<_  ( P 
 .\/  Q )  /\  -.  ( R `  G ) 
 .<_  ( P  .\/  Q )  /\  ( R `  F )  =/=  ( R `  G ) ) )  ->  ( (
 ( F `  ( G `  P ) ) 
 .\/  P )  ./\  (
 ( F `  ( G `  Q ) ) 
 .\/  Q ) )  =/= 
 .0.  )
 
Theoremcdlemg12f 34127 TODO: FIX COMMENT. (Contributed by NM, 6-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( -.  ( R `  F )  .<_  ( P  .\/  Q )  /\  -.  ( R `  G )  .<_  ( P  .\/  Q )
 )  /\  ( R `  F )  =/=  ( R `  G )  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q ) ) )  ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  ( Q  .\/  ( F `  ( G `  Q ) ) ) )  .<_  ( ( P  .\/  ( F `  ( G `  P ) ) )  ./\  W ) )
 
Theoremcdlemg12g 34128 TODO: FIX COMMENT. TODO: Combine with cdlemg12f 34127. (Contributed by NM, 6-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( -.  ( R `  F )  .<_  ( P  .\/  Q )  /\  -.  ( R `  G )  .<_  ( P  .\/  Q )
 )  /\  ( R `  F )  =/=  ( R `  G )  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q ) ) )  ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  ( Q  .\/  ( F `  ( G `  Q ) ) ) )  =  ( ( P  .\/  ( F `  ( G `  P ) ) ) 
 ./\  W ) )
 
Theoremcdlemg12 34129 TODO: FIX COMMENT. (Contributed by NM, 6-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( -.  ( R `  F )  .<_  ( P  .\/  Q )  /\  -.  ( R `  G )  .<_  ( P  .\/  Q )
 )  /\  ( R `  F )  =/=  ( R `  G )  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q ) ) )  ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )
 )
 
Theoremcdlemg13a 34130 TODO: FIX COMMENT. (Contributed by NM, 6-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T )  /\  ( ( F `
  P )  =/= 
 P  /\  ( R `  F )  =  ( R `  G ) 
 /\  ( ( F `
  ( G `  P ) )  .\/  ( F `  ( G `
  Q ) ) )  =/=  ( P 
 .\/  Q ) ) ) 
 ->  ( P  .\/  ( F `  ( G `  P ) ) )  =  ( ( G `
  P )  .\/  ( F `  ( G `
  P ) ) ) )
 
Theoremcdlemg13 34131 TODO: FIX COMMENT. (Contributed by NM, 6-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T )  /\  ( ( F `
  P )  =/= 
 P  /\  ( R `  F )  =  ( R `  G ) 
 /\  ( ( F `
  ( G `  P ) )  .\/  ( F `  ( G `
  Q ) ) )  =/=  ( P 
 .\/  Q ) ) ) 
 ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )
 )
 
Theoremcdlemg14f 34132 TODO: FIX COMMENT. (Contributed by NM, 6-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  ( F `  P )  =  P )
 )  ->  ( ( P  .\/  ( F `  ( G `  P ) ) )  ./\  W )  =  ( ( Q 
 .\/  ( F `  ( G `  Q ) ) )  ./\  W ) )
 
Theoremcdlemg14g 34133 TODO: FIX COMMENT. (Contributed by NM, 22-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  ( G `  P )  =  P )
 )  ->  ( ( P  .\/  ( F `  ( G `  P ) ) )  ./\  W )  =  ( ( Q 
 .\/  ( F `  ( G `  Q ) ) )  ./\  W ) )
 
Theoremcdlemg15a 34134 Eliminate the  ( F `  P )  =/=  P condition from cdlemg13 34131. TODO: FIX COMMENT. (Contributed by NM, 6-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T )  /\  ( ( R `
  F )  =  ( R `  G )  /\  ( ( F `
  ( G `  P ) )  .\/  ( F `  ( G `
  Q ) ) )  =/=  ( P 
 .\/  Q ) ) ) 
 ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )
 )
 
Theoremcdlemg15 34135 Eliminate the  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `
 Q ) ) )  =/=  ( P 
.\/  Q ) condition from cdlemg13 34131. TODO: FIX COMMENT. (Contributed by NM, 25-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T )  /\  ( R `  F )  =  ( R `  G ) ) 
 ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )
 )
 
Theoremcdlemg16 34136 Part of proof of Lemma G of [Crawley] p. 116; 2nd line p. 117, which says that (our) cdlemg10 34120 "implies (2)" (of p. 116). No details are provided by the authors, so there may be a shorter proof; but ours requires the 14 lemmas, one using Desargues' law dalaw 33363, in order to make this inference. This final step eliminates the  ( R `  F )  =/=  ( R `  G ) condition from cdlemg12 34129. TODO: FIX COMMENT. TODO: should we also eliminate  P  =/=  Q here (or earlier)? Do it if we don't need to add it in for something else later. (Contributed by NM, 6-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( -.  ( R `  F )  .<_  ( P  .\/  Q )  /\  -.  ( R `  G )  .<_  ( P 
 .\/  Q )  /\  (
 ( F `  ( G `  P ) ) 
 .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q ) ) )  ->  ( ( P  .\/  ( F `  ( G `  P ) ) )  ./\  W )  =  ( ( Q 
 .\/  ( F `  ( G `  Q ) ) )  ./\  W ) )
 
Theoremcdlemg16ALTN 34137 This version of cdlemg16 34136 uses cdlemg15a 34134 instead of cdlemg15 34135, in case cdlemg15 34135 ends up not being needed. TODO: FIX COMMENT. (Contributed by NM, 6-May-2013.) (New usage is discouraged.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H  /\  ( F  e.  T  /\  G  e.  T ) )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) 
 /\  P  =/=  Q )  /\  ( ( ( F `  ( G `
  P ) ) 
 .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q )  /\  -.  ( R `  F )  .<_  ( P  .\/  Q )  /\  -.  ( R `  G )  .<_  ( P  .\/  Q )
 ) )  ->  (
 ( P  .\/  ( F `  ( G `  P ) ) ) 
 ./\  W )  =  ( ( Q  .\/  ( F `  ( G `  Q ) ) ) 
 ./\  W ) )
 
Theoremcdlemg16z 34138 Eliminate  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `
 Q ) ) )  =/=  ( P 
.\/  Q ) condition from cdlemg16 34136. TODO: would it help to also eliminate  P  =/=  Q here or later? (Contributed by NM, 25-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( -.  ( R `  F )  .<_  ( P  .\/  Q )  /\  -.  ( R `  G )  .<_  ( P 
 .\/  Q ) ) ) 
 ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )
 )
 
Theoremcdlemg16zz 34139 Eliminate  P  =/=  Q from cdlemg16z 34138. TODO: Use this only if needed. (Contributed by NM, 26-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  F  e.  T )  /\  ( G  e.  T  /\  -.  ( R `  F )  .<_  ( P 
 .\/  Q )  /\  -.  ( R `  G ) 
 .<_  ( P  .\/  Q ) ) )  ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )
 )
 
Theoremcdlemg17a 34140 TODO: FIX COMMENT. (Contributed by NM, 8-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( G  e.  T  /\  ( R `  G )  .<_  ( P 
 .\/  Q ) ) ) 
 ->  ( G `  P )  .<_  ( P  .\/  Q ) )
 
Theoremcdlemg17b 34141* Part of proof of Lemma G in [Crawley] p. 117, 4th line. Whenever (in their terminology) p  \/ q/0 (i.e. the sublattice from 0 to p  \/ q) contains precisely three atoms and g is not the identity, g(p) = q. See also comments under cdleme0nex 33768. (Contributed by NM, 8-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( G  e.  T  /\  P  =/=  Q )  /\  ( ( G `
  P )  =/= 
 P  /\  ( R `  G )  .<_  ( P 
 .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( G `  P )  =  Q )
 
Theoremcdlemg17dN 34142* TODO: fix comment. (Contributed by NM, 9-May-2013.) (New usage is discouraged.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H  /\  G  e.  T )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  P  =/=  Q )  /\  ( ( R `  G )  .<_  ( P 
 .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) )  /\  ( G `  P )  =/=  P ) ) 
 ->  ( R `  G )  =  ( ( P  .\/  Q )  ./\  W ) )
 
Theoremcdlemg17dALTN 34143 Same as cdlemg17dN 34142 with fewer antecedents but longer proof TODO: fix comment. (Contributed by NM, 9-May-2013.) (New usage is discouraged.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H  /\  G  e.  T )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  Q  e.  A  /\  P  =/=  Q )  /\  ( ( R `
  G )  .<_  ( P  .\/  Q )  /\  ( G `  P )  =/=  P ) ) 
 ->  ( R `  G )  =  ( ( P  .\/  Q )  ./\  W ) )
 
Theoremcdlemg17e 34144* TODO: fix comment. (Contributed by NM, 8-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( G `
  P )  =/= 
 P  /\  ( R `  G )  .<_  ( P 
 .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( ( F `  P )  .\/  ( F `  Q ) )  =  ( ( F `  P ) 
 .\/  ( R `  G ) ) )
 
Theoremcdlemg17f 34145* TODO: fix comment. (Contributed by NM, 8-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( G `
  P )  =/= 
 P  /\  ( R `  G )  .<_  ( P 
 .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( ( F `  P )  .\/  ( F `  Q ) )  =  ( ( F `  P ) 
 .\/  ( G `  ( F `  P ) ) ) )
 
Theoremcdlemg17g 34146* TODO: fix comment. (Contributed by NM, 9-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( G `
  P )  =/= 
 P  /\  ( R `  G )  .<_  ( P 
 .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( G `  ( F `  P ) )  .<_  ( ( F `  P ) 
 .\/  ( F `  Q ) ) )
 
Theoremcdlemg17h 34147* TODO: fix comment. (Contributed by NM, 10-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( ( S  e.  A  /\  -.  S  .<_  W )  /\  ( F  e.  T  /\  G  e.  T ) 
 /\  ( P  =/=  Q 
 /\  S  .<_  ( ( F `  P ) 
 .\/  ( F `  Q ) ) ) )  /\  ( ( G `  P )  =/=  P  /\  ( R `  G )  .<_  ( P  .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P 
 .\/  r )  =  ( Q  .\/  r
 ) ) ) ) 
 ->  ( S  =  ( F `  P )  \/  S  =  ( F `  Q ) ) )
 
Theoremcdlemg17i 34148* TODO: fix comment. (Contributed by NM, 10-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( G `
  P )  =/= 
 P  /\  ( R `  G )  .<_  ( P 
 .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( G `  ( F `  P ) )  =  ( F `  Q ) )
 
Theoremcdlemg17ir 34149* TODO: fix comment. (Contributed by NM, 13-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( G `
  P )  =/= 
 P  /\  ( R `  G )  .<_  ( P 
 .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( F `  ( G `  P ) )  =  ( F `  Q ) )
 
Theoremcdlemg17j 34150* TODO: fix comment. (Contributed by NM, 11-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( G `
  P )  =/= 
 P  /\  ( R `  G )  .<_  ( P 
 .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( G `  ( F `  P ) )  =  ( F `  ( G `  P ) ) )
 
Theoremcdlemg17pq 34151* Utility theorem for swapping  P and  Q. TODO: fix comment. (Contributed by NM, 11-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( G `
  P )  =/= 
 P  /\  ( R `  G )  .<_  ( P 
 .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( (
 ( K  e.  HL  /\  W  e.  H ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  ( P  e.  A  /\  -.  P  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  Q  =/=  P ) 
 /\  ( ( G `
  Q )  =/= 
 Q  /\  ( R `  G )  .<_  ( Q 
 .\/  P )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( Q  .\/  r )  =  ( P  .\/  r ) ) ) ) )
 
Theoremcdlemg17bq 34152* cdlemg17b 34141 with  P and  Q swapped. Antecedent  F  e.  ( T `  W ) is redundant for easier use. TODO: should we have redundant antecedent for cdlemg17b 34141 also? (Contributed by NM, 13-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( G `
  P )  =/= 
 P  /\  ( R `  G )  .<_  ( P 
 .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( G `  Q )  =  P )
 
Theoremcdlemg17iqN 34153* cdlemg17i 34148 with  P and  Q swapped. (Contributed by NM, 13-May-2013.) (New usage is discouraged.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H  /\  ( F  e.  T  /\  G  e.  T ) )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) 
 /\  P  =/=  Q )  /\  ( ( R `
  G )  .<_  ( P  .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P 
 .\/  r )  =  ( Q  .\/  r
 ) )  /\  ( G `  P )  =/= 
 P ) )  ->  ( G `  ( F `
  Q ) )  =  ( F `  P ) )
 
Theoremcdlemg17irq 34154* cdlemg17ir 34149 with  P and  Q swapped. (Contributed by NM, 13-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( G `
  P )  =/= 
 P  /\  ( R `  G )  .<_  ( P 
 .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( F `  ( G `  Q ) )  =  ( F `  P ) )
 
Theoremcdlemg17jq 34155* cdlemg17j 34150 with  P and  Q swapped. (Contributed by NM, 13-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( G `
  P )  =/= 
 P  /\  ( R `  G )  .<_  ( P 
 .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( G `  ( F `  Q ) )  =  ( F `  ( G `  Q ) ) )
 
Theoremcdlemg17 34156* Part of Lemma G of [Crawley] p. 117, lines 7 and 8. We show an argument whose value at  G equals itself. TODO: fix comment. (Contributed by NM, 12-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( G `
  P )  =/= 
 P  /\  ( R `  G )  .<_  ( P 
 .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( G `  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  ( Q  .\/  ( F `  ( G `  Q ) ) ) ) )  =  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  ( Q  .\/  ( F `  ( G `  Q ) ) ) ) )
 
Theoremcdlemg18a 34157 Show two lines are different. TODO: fix comment. (Contributed by NM, 14-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( P  e.  A  /\  Q  e.  A  /\  F  e.  T )  /\  ( P  =/=  Q  /\  ( ( F `  Q )  .\/  ( F `
  P ) )  =/=  ( P  .\/  Q ) ) )  ->  ( P  .\/  ( F `
  Q ) )  =/=  ( Q  .\/  ( F `  P ) ) )
 
Theoremcdlemg18b 34158 Lemma for cdlemg18c 34159. TODO: fix comment. (Contributed by NM, 15-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  U  =  ( ( P  .\/  Q )  ./\  W )   =>    |-  (
 ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) 
 /\  F  e.  T )  /\  ( P  =/=  Q 
 /\  ( F `  P )  =/=  Q  /\  ( ( F `  Q )  .\/  ( F `
  P ) )  =/=  ( P  .\/  Q ) ) )  ->  -.  P  .<_  ( U  .\/  ( F `  Q ) ) )
 
Theoremcdlemg18c 34159 Show two lines intersect at an atom. TODO: fix comment. (Contributed by NM, 15-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  U  =  ( ( P  .\/  Q )  ./\  W )   =>    |-  (
 ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) 
 /\  F  e.  T )  /\  ( P  =/=  Q 
 /\  ( F `  P )  =/=  Q  /\  ( ( F `  Q )  .\/  ( F `
  P ) )  =/=  ( P  .\/  Q ) ) )  ->  ( ( P  .\/  ( F `  Q ) )  ./\  ( Q  .\/  ( F `  P ) ) )  e.  A )
 
Theoremcdlemg18d 34160* Show two lines intersect at an atom. TODO: fix comment. (Contributed by NM, 15-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( ( F  e.  T  /\  G  e.  T )  /\  P  =/=  Q  /\  ( G `
  P )  =/= 
 P )  /\  (
 ( R `  G )  .<_  ( P  .\/  Q )  /\  ( ( F `  ( G `
  P ) ) 
 .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q )  /\  -. 
 E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( ( P  .\/  ( F `  ( G `  P ) ) )  ./\  ( Q  .\/  ( F `  ( G `  Q ) ) ) )  e.  A )
 
Theoremcdlemg18 34161* Show two lines intersect at an atom. TODO: fix comment. (Contributed by NM, 15-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( ( F  e.  T  /\  G  e.  T )  /\  P  =/=  Q  /\  ( G `
  P )  =/= 
 P )  /\  (
 ( R `  G )  .<_  ( P  .\/  Q )  /\  ( ( F `  ( G `
  P ) ) 
 .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q )  /\  -. 
 E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( ( P  .\/  ( F `  ( G `  P ) ) )  ./\  ( Q  .\/  ( F `  ( G `  Q ) ) ) )  .<_  W )
 
Theoremcdlemg19a 34162* Show two lines intersect at an atom. TODO: fix comment. (Contributed by NM, 15-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( ( F  e.  T  /\  G  e.  T )  /\  P  =/=  Q  /\  ( G `
  P )  =/= 
 P )  /\  (
 ( R `  G )  .<_  ( P  .\/  Q )  /\  ( ( F `  ( G `
  P ) ) 
 .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q )  /\  -. 
 E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( ( P  .\/  ( F `  ( G `  P ) ) )  ./\  ( Q  .\/  ( F `  ( G `  Q ) ) ) )  =  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )
 )
 
Theoremcdlemg19 34163* Show two lines intersect at an atom. TODO: fix comment. (Contributed by NM, 15-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( ( F  e.  T  /\  G  e.  T )  /\  P  =/=  Q  /\  ( G `
  P )  =/= 
 P )  /\  (
 ( R `  G )  .<_  ( P  .\/  Q )  /\  ( ( F `  ( G `
  P ) ) 
 .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q )  /\  -. 
 E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( ( P  .\/  ( F `  ( G `  P ) ) )  ./\  W )  =  ( ( Q 
 .\/  ( F `  ( G `  Q ) ) )  ./\  W ) )
 
Theoremcdlemg20 34164* Show two lines intersect at an atom. TODO: fix comment. (Contributed by NM, 23-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( R `
  G )  .<_  ( P  .\/  Q )  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P 
 .\/  r )  =  ( Q  .\/  r
 ) ) ) ) 
 ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )
 )
 
Theoremcdlemg21 34165* Version of cdlemg19 with  ( R `  F
)  .<_  ( P  .\/  Q ) instead of  ( R `  G )  .<_  ( P 
.\/  Q ) as a condition. (Contributed by NM, 23-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( ( F  e.  T  /\  G  e.  T )  /\  P  =/=  Q  /\  ( F `
  P )  =/= 
 P )  /\  (
 ( R `  F )  .<_  ( P  .\/  Q )  /\  ( ( F `  ( G `
  P ) ) 
 .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q )  /\  -. 
 E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( ( P  .\/  ( F `  ( G `  P ) ) )  ./\  W )  =  ( ( Q 
 .\/  ( F `  ( G `  Q ) ) )  ./\  W ) )
 
Theoremcdlemg22 34166* cdlemg21 34165 with  ( F `  P )  =/=  P condition removed. (Contributed by NM, 23-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( R `
  F )  .<_  ( P  .\/  Q )  /\  ( ( F `  ( G `  P ) )  .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q )  /\  -.  E. r  e.  A  ( -.  r  .<_  W  /\  ( P 
 .\/  r )  =  ( Q  .\/  r
 ) ) ) ) 
 ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )
 )
 
Theoremcdlemg24 34167* Combine cdlemg16z 34138 and cdlemg22 34166. TODO: Fix comment. (Contributed by NM, 24-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) ) 
 /\  ( F  e.  T  /\  G  e.  T  /\  P  =/=  Q ) 
 /\  ( ( ( F `  ( G `
  P ) ) 
 .\/  ( F `  ( G `  Q ) ) )  =/=  ( P  .\/  Q )  /\  -. 
 E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( ( P  .\/  ( F `  ( G `  P ) ) )  ./\  W )  =  ( ( Q 
 .\/  ( F `  ( G `  Q ) ) )  ./\  W ) )
 
Theoremcdlemg37 34168* Use cdlemg8 34110 to eliminate the  =/=  ( P  .\/  Q
) condition of cdlemg24 34167. (Contributed by NM, 31-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  F  e.  T )  /\  ( G  e.  T  /\  P  =/=  Q  /\  -. 
 E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  ( ( P  .\/  ( F `  ( G `  P ) ) )  ./\  W )  =  ( ( Q 
 .\/  ( F `  ( G `  Q ) ) )  ./\  W ) )
 
Theoremcdlemg25zz 34169 cdlemg16zz 34139 restated for easier studying. TODO: Discard this after everything is figured out. (Contributed by NM, 26-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( z  e.  A  /\  -.  z  .<_  W )  /\  F  e.  T )  /\  ( G  e.  T  /\  -.  ( R `  F )  .<_  ( P 
 .\/  z )  /\  -.  ( R `  G )  .<_  ( P  .\/  z ) ) ) 
 ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( z  .\/  ( F `  ( G `
  z ) ) )  ./\  W )
 )
 
Theoremcdlemg26zz 34170 cdlemg16zz 34139 restated for easier studying. TODO: Discard this after everything is figured out. (Contributed by NM, 26-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( ( Q  e.  A  /\  -.  Q  .<_  W )  /\  ( z  e.  A  /\  -.  z  .<_  W )  /\  F  e.  T )  /\  ( G  e.  T  /\  -.  ( R `  F )  .<_  ( Q 
 .\/  z )  /\  -.  ( R `  G )  .<_  ( Q  .\/  z ) ) ) 
 ->  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )  =  ( ( z  .\/  ( F `  ( G `
  z ) ) )  ./\  W )
 )
 
Theoremcdlemg27a 34171 For use with case when  ( P  .\/  v
)  ./\  ( Q  .\/  ( R `  F
) ) or  ( P  .\/  v )  ./\  ( Q  .\/  ( R `  F ) ) is zero, letting us establish  -.  z  .<_  W  /\  z  .<_  ( P 
.\/  v ) via 4atex 33553. TODO: Fix comment. (Contributed by NM, 28-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( v  e.  A  /\  v  .<_  W ) )  /\  ( z  e.  A  /\  F  e.  T ) 
 /\  ( v  =/=  ( R `  F )  /\  z  .<_  ( P 
 .\/  v )  /\  ( F `  P )  =/=  P ) ) 
 ->  -.  ( R `  F )  .<_  ( P 
 .\/  z ) )
 
Theoremcdlemg28a 34172 Part of proof of Lemma G of [Crawley] p. 116. First equality of the equation of line 14 on p. 117. (Contributed by NM, 29-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H ) 
 /\  ( P  e.  A  /\  -.  P  .<_  W )  /\  ( v  e.  A  /\  v  .<_  W ) )  /\  ( ( z  e.  A  /\  -.  z  .<_  W )  /\  F  e.  T  /\  G  e.  T )  /\  ( ( v  =/=  ( R `
  F )  /\  v  =/=  ( R `  G ) )  /\  z  .<_  ( P  .\/  v )  /\  ( ( F `  P )  =/=  P  /\  ( G `  P )  =/= 
 P ) ) ) 
 ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( z  .\/  ( F `  ( G `
  z ) ) )  ./\  W )
 )
 
Theoremcdlemg31b0N 34173 TODO: Fix comment. (Contributed by NM, 30-May-2013.) (New usage is discouraged.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  N  =  ( ( P  .\/  v )  ./\  ( Q 
 .\/  ( R `  F ) ) )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H  /\  F  e.  T )  /\  ( ( P  e.  A  /\  -.  P  .<_  W )  /\  ( Q  e.  A  /\  -.  Q  .<_  W ) )  /\  ( ( v  e.  A  /\  v  .<_  W )  /\  v  =/=  ( R `  F )  /\  ( F `
  P )  =/= 
 P ) )  ->  ( N  e.  A  \/  N  =  ( 0. `  K ) ) )
 
Theoremcdlemg31b0a 34174 TODO: Fix comment. (Contributed by NM, 30-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  N  =  ( ( P  .\/  v )  ./\  ( Q 
 .\/  ( R `  F ) ) )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  (
 ( P  e.  A  /\  -.  P  .<_  W ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  ( v  e.  A  /\  v  .<_  W ) )  /\  ( F  e.  T  /\  v  =/=  ( R `  F ) ) )  ->  ( N  e.  A  \/  N  =  ( 0. `  K ) ) )
 
Theoremcdlemg27b 34175 TODO: Fix comment. (Contributed by NM, 28-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  N  =  ( ( P  .\/  v )  ./\  ( Q 
 .\/  ( R `  F ) ) )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( P  e.  A  /\  -.  P  .<_  W ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W ) )  /\  (
 z  e.  A  /\  ( v  e.  A  /\  v  .<_  W ) 
 /\  ( F  e.  T  /\  z  =/=  N ) )  /\  ( v  =/=  ( R `  F )  /\  z  .<_  ( P  .\/  v )  /\  ( F `  P )  =/=  P ) ) 
 ->  -.  ( R `  F )  .<_  ( Q 
 .\/  z ) )
 
Theoremcdlemg31a 34176 TODO: fix comment. (Contributed by NM, 29-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  N  =  ( ( P  .\/  v )  ./\  ( Q 
 .\/  ( R `  F ) ) )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( P  e.  A  /\  Q  e.  A )  /\  ( v  e.  A  /\  F  e.  T ) )  ->  N  .<_  ( P  .\/  v )
 )
 
Theoremcdlemg31b 34177 TODO: fix comment. (Contributed by NM, 29-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  N  =  ( ( P  .\/  v )  ./\  ( Q 
 .\/  ( R `  F ) ) )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( P  e.  A  /\  Q  e.  A )  /\  ( v  e.  A  /\  F  e.  T ) )  ->  N  .<_  ( Q  .\/  ( R `  F ) ) )
 
Theoremcdlemg31c 34178 Show that when  N is an atom, it is not under  W. TODO: Is there a shorter direct proof? TODO: should we eliminate  ( F `  P )  =/=  P here? (Contributed by NM, 29-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  N  =  ( ( P  .\/  v )  ./\  ( Q 
 .\/  ( R `  F ) ) )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( P  e.  A  /\  -.  P  .<_  W ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W ) )  /\  (
 ( v  e.  A  /\  v  .<_  W ) 
 /\  F  e.  T )  /\  ( v  =/=  ( R `  F )  /\  ( F `  P )  =/=  P  /\  N  e.  A )
 )  ->  -.  N  .<_  W )
 
Theoremcdlemg31d 34179 Eliminate  ( F `  P )  =/=  P from cdlemg31c 34178. TODO: Prove directly. TODO: do we need to eliminate  ( F `  P )  =/=  P? It might be better to do this all at once at the end. See also cdlemg29 34184 vs. cdlemg28 34183. (Contributed by NM, 29-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  N  =  ( ( P  .\/  v )  ./\  ( Q 
 .\/  ( R `  F ) ) )   =>    |-  ( ( ( K  e.  HL  /\  W  e.  H )  /\  (
 ( P  e.  A  /\  -.  P  .<_  W ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W )  /\  ( v  e.  A  /\  v  .<_  W ) )  /\  ( F  e.  T  /\  v  =/=  ( R `  F )  /\  N  e.  A )
 )  ->  -.  N  .<_  W )
 
Theoremcdlemg33b0 34180* TODO: Fix comment. (Contributed by NM, 30-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  N  =  ( ( P  .\/  v )  ./\  ( Q 
 .\/  ( R `  F ) ) )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( P  e.  A  /\  -.  P  .<_  W ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W ) )  /\  (
 ( v  e.  A  /\  v  .<_  W ) 
 /\  N  e.  A  /\  F  e.  T ) 
 /\  ( P  =/=  Q 
 /\  v  =/=  ( R `  F )  /\  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  E. z  e.  A  ( -.  z  .<_  W  /\  ( z  =/=  N  /\  z  .<_  ( P  .\/  v
 ) ) ) )
 
Theoremcdlemg33c0 34181* TODO: Fix comment. (Contributed by NM, 30-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  N  =  ( ( P  .\/  v )  ./\  ( Q 
 .\/  ( R `  F ) ) )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( P  e.  A  /\  -.  P  .<_  W ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W ) )  /\  (
 ( v  e.  A  /\  v  .<_  W ) 
 /\  F  e.  T )  /\  ( P  =/=  Q 
 /\  v  =/=  ( R `  F )  /\  E. r  e.  A  ( -.  r  .<_  W  /\  ( P  .\/  r )  =  ( Q  .\/  r ) ) ) )  ->  E. z  e.  A  ( -.  z  .<_  W  /\  z  .<_  ( P  .\/  v )
 ) )
 
Theoremcdlemg28b 34182* Part of proof of Lemma G of [Crawley] p. 116. Second equality of the equation of line 14 on p. 117. Note that  -.  z  .<_  W is redundant here (but simplifies cdlemg28 34183.) (Contributed by NM, 29-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  N  =  ( ( P  .\/  v )  ./\  ( Q 
 .\/  ( R `  F ) ) )   &    |-  O  =  ( ( P  .\/  v )  ./\  ( Q  .\/  ( R `
  G ) ) )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( P  e.  A  /\  -.  P  .<_  W ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W ) )  /\  (
 ( v  e.  A  /\  v  .<_  W ) 
 /\  ( z  e.  A  /\  -.  z  .<_  W )  /\  ( F  e.  T  /\  G  e.  T )
 )  /\  ( (
 z  =/=  N  /\  z  =/=  O  /\  z  .<_  ( P  .\/  v
 ) )  /\  (
 v  =/=  ( R `  F )  /\  v  =/=  ( R `  G ) )  /\  ( ( F `  P )  =/=  P  /\  ( G `  P )  =/= 
 P ) ) ) 
 ->  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )  =  ( ( z  .\/  ( F `  ( G `
  z ) ) )  ./\  W )
 )
 
Theoremcdlemg28 34183* Part of proof of Lemma G of [Crawley] p. 116. Chain the equalities of line 14 on p. 117. TODO: rearrange hypotheses in the order of cdlemg29 34184 (and maybe leading up to this too)? (Contributed by NM, 29-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  N  =  ( ( P  .\/  v )  ./\  ( Q 
 .\/  ( R `  F ) ) )   &    |-  O  =  ( ( P  .\/  v )  ./\  ( Q  .\/  ( R `
  G ) ) )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( P  e.  A  /\  -.  P  .<_  W ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W ) )  /\  (
 ( v  e.  A  /\  v  .<_  W ) 
 /\  ( z  e.  A  /\  -.  z  .<_  W )  /\  ( F  e.  T  /\  G  e.  T )
 )  /\  ( (
 z  =/=  N  /\  z  =/=  O  /\  z  .<_  ( P  .\/  v
 ) )  /\  (
 v  =/=  ( R `  F )  /\  v  =/=  ( R `  G ) )  /\  ( ( F `  P )  =/=  P  /\  ( G `  P )  =/= 
 P ) ) ) 
 ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )
 )
 
Theoremcdlemg29 34184* Eliminate  ( F `  P )  =/=  P and  ( G `  P )  =/=  P from cdlemg28 34183. TODO: would it be better to do this later? (Contributed by NM, 29-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  N  =  ( ( P  .\/  v )  ./\  ( Q 
 .\/  ( R `  F ) ) )   &    |-  O  =  ( ( P  .\/  v )  ./\  ( Q  .\/  ( R `
  G ) ) )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( P  e.  A  /\  -.  P  .<_  W ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W ) )  /\  (
 ( v  e.  A  /\  v  .<_  W ) 
 /\  ( z  e.  A  /\  -.  z  .<_  W )  /\  ( F  e.  T  /\  G  e.  T )
 )  /\  ( (
 z  =/=  N  /\  z  =/=  O )  /\  z  .<_  ( P  .\/  v )  /\  ( v  =/=  ( R `  F )  /\  v  =/=  ( R `  G ) ) ) ) 
 ->  ( ( P  .\/  ( F `  ( G `
  P ) ) )  ./\  W )  =  ( ( Q  .\/  ( F `  ( G `
  Q ) ) )  ./\  W )
 )
 
Theoremcdlemg33a 34185* TODO: Fix comment. (Contributed by NM, 29-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &    |-  H  =  ( LHyp `  K )   &    |-  T  =  ( ( LTrn `  K ) `  W )   &    |-  R  =  ( ( trL `  K ) `  W )   &    |-  N  =  ( ( P  .\/  v )  ./\  ( Q 
 .\/  ( R `  F ) ) )   &    |-  O  =  ( ( P  .\/  v )  ./\  ( Q  .\/  ( R `
  G ) ) )   =>    |-  ( ( ( ( K  e.  HL  /\  W  e.  H )  /\  ( P  e.  A  /\  -.  P  .<_  W ) 
 /\  ( Q  e.  A  /\  -.  Q  .<_  W ) )  /\  (
 ( v  e.  A  /\  v  .<_  W ) 
 /\  ( N  e.  A  /\  O  e.  A )  /\  ( F  e.  T  /\  G  e.  T ) )  /\  ( ( P  =/=  Q  /\  N  =/=  O )  /\  v  =/=  ( R `  F )  /\  E. r  e.  A  ( -.  r  .<_  W  /\  ( P 
 .\/  r )  =  ( Q  .\/  r
 ) ) ) ) 
 ->  E. z  e.  A  ( -.  z  .<_  W  /\  ( z  =/=  N  /\  z  =/=  O  /\  z  .<_  ( P  .\/  v
 ) ) ) )
 
Theoremcdlemg33b 34186* TODO: Fix comment. (Contributed by NM, 30-May-2013.)
 |-  .<_  =  ( le `  K )   &    |- 
 .\/  =  ( join `  K )   &    |-  ./\  =  ( meet `  K )   &    |-  A  =  ( Atoms `  K )   &