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Theorem exmidel 4342
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 4333 . . 3  |-  (EXMID  -> DECID  x  e.  y
)
21alrimivv 1928 . 2  |-  (EXMID  ->  A. x A. yDECID  x  e.  y )
3 0ex 4260 . . . 4  |-  (/)  e.  _V
4 eleq1 2301 . . . . . 6  |-  ( x  =  (/)  ->  ( x  e.  y  <->  (/)  e.  y ) )
54dcbid 850 . . . . 5  |-  ( x  =  (/)  ->  (DECID  x  e.  y  <-> DECID  (/) 
e.  y ) )
65albidv 1877 . . . 4  |-  ( x  =  (/)  ->  ( A. yDECID  x  e.  y  <->  A. yDECID  (/)  e.  y ) )
73, 6spcv 2919 . . 3  |-  ( A. x A. yDECID  x  e.  y  ->  A. yDECID  (/)  e.  y )
8 exmid0el 4341 . . 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
This proof depends on syntax axioms:    <-> wb 105  DECID wdc 846   A.wal 1400    = wceq 1402    e. wcel 2209   (/)c0 3520  EXMIDwem 4331
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4249  ax-nul 4259  ax-pow 4311
This proof depends on definitions:  df-bi 117  df-dc 847  df-tru 1405  df-nf 1514  df-sb 1816  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-rab 2537  df-v 2823  df-dif 3222  df-in 3226  df-ss 3233  df-nul 3521  df-pw 3690  df-sn 3715  df-exmid 4332
This theorem is used by: (None)
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