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Theorem exmidel 4289
Description: Excluded middle is equivalent to decidability of membership for two arbitrary sets. (Contributed by Jim Kingdon, 18-Jun-2022.)
Assertion
Ref Expression
exmidel  |-  (EXMID  <->  A. x A. yDECID  x  e.  y )
Distinct variable group:    x, y

Proof of Theorem exmidel
StepHypRef Expression
1 exmidexmid 4280 . . 3  |-  (EXMID  -> DECID  x  e.  y
)
21alrimivv 1921 . 2  |-  (EXMID  ->  A. x A. yDECID  x  e.  y )
3 0ex 4211 . . . 4  |-  (/)  e.  _V
4 eleq1 2292 . . . . . 6  |-  ( x  =  (/)  ->  ( x  e.  y  <->  (/)  e.  y ) )
54dcbid 843 . . . . 5  |-  ( x  =  (/)  ->  (DECID  x  e.  y  <-> DECID  (/) 
e.  y ) )
65albidv 1870 . . . 4  |-  ( x  =  (/)  ->  ( A. yDECID  x  e.  y  <->  A. yDECID  (/)  e.  y ) )
73, 6spcv 2897 . . 3  |-  ( A. x A. yDECID  x  e.  y  ->  A. yDECID  (/)  e.  y )
8 exmid0el 4288 . . 3  |-  (EXMID  <->  A. yDECID  (/)  e.  y )
97, 8sylibr 134 . 2  |-  ( A. x A. yDECID  x  e.  y  -> EXMID )
102, 9impbii 126 1  |-  (EXMID  <->  A. x A. yDECID  x  e.  y )
Colors of variables: wff set class
Syntax hints:    <-> wb 105  DECID wdc 839   A.wal 1393    = wceq 1395    e. wcel 2200   (/)c0 3491  EXMIDwem 4278
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 617  ax-in2 618  ax-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-14 2203  ax-ext 2211  ax-sep 4202  ax-nul 4210  ax-pow 4258
This theorem depends on definitions:  df-bi 117  df-dc 840  df-tru 1398  df-nf 1507  df-sb 1809  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-rab 2517  df-v 2801  df-dif 3199  df-in 3203  df-ss 3210  df-nul 3492  df-pw 3651  df-sn 3672  df-exmid 4279
This theorem is referenced by: (None)
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