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Theorem exmidel 4184
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 4175 . . 3  |-  (EXMID  -> DECID  x  e.  y
)
21alrimivv 1863 . 2  |-  (EXMID  ->  A. x A. yDECID  x  e.  y )
3 0ex 4109 . . . 4  |-  (/)  e.  _V
4 eleq1 2229 . . . . . 6  |-  ( x  =  (/)  ->  ( x  e.  y  <->  (/)  e.  y ) )
54dcbid 828 . . . . 5  |-  ( x  =  (/)  ->  (DECID  x  e.  y  <-> DECID  (/) 
e.  y ) )
65albidv 1812 . . . 4  |-  ( x  =  (/)  ->  ( A. yDECID  x  e.  y  <->  A. yDECID  (/)  e.  y ) )
73, 6spcv 2820 . . 3  |-  ( A. x A. yDECID  x  e.  y  ->  A. yDECID  (/)  e.  y )
8 exmid0el 4183 . . 3  |-  (EXMID  <->  A. yDECID  (/)  e.  y )
97, 8sylibr 133 . 2  |-  ( A. x A. yDECID  x  e.  y  -> EXMID )
102, 9impbii 125 1  |-  (EXMID  <->  A. x A. yDECID  x  e.  y )
Colors of variables: wff set class
Syntax hints:    <-> wb 104  DECID wdc 824   A.wal 1341    = wceq 1343    e. wcel 2136   (/)c0 3409  EXMIDwem 4173
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 604  ax-in2 605  ax-io 699  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-10 1493  ax-11 1494  ax-i12 1495  ax-bndl 1497  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-14 2139  ax-ext 2147  ax-sep 4100  ax-nul 4108  ax-pow 4153
This theorem depends on definitions:  df-bi 116  df-dc 825  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2297  df-rab 2453  df-v 2728  df-dif 3118  df-in 3122  df-ss 3129  df-nul 3410  df-pw 3561  df-sn 3582  df-exmid 4174
This theorem is referenced by: (None)
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