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Theorem exmidel 4136
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 4128 . . 3  |-  (EXMID  -> DECID  x  e.  y
)
21alrimivv 1848 . 2  |-  (EXMID  ->  A. x A. yDECID  x  e.  y )
3 0ex 4063 . . . 4  |-  (/)  e.  _V
4 eleq1 2203 . . . . . 6  |-  ( x  =  (/)  ->  ( x  e.  y  <->  (/)  e.  y ) )
54dcbid 824 . . . . 5  |-  ( x  =  (/)  ->  (DECID  x  e.  y  <-> DECID  (/) 
e.  y ) )
65albidv 1797 . . . 4  |-  ( x  =  (/)  ->  ( A. yDECID  x  e.  y  <->  A. yDECID  (/)  e.  y ) )
73, 6spcv 2783 . . 3  |-  ( A. x A. yDECID  x  e.  y  ->  A. yDECID  (/)  e.  y )
8 exmid0el 4135 . . 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 820   A.wal 1330    = wceq 1332    e. wcel 1481   (/)c0 3368  EXMIDwem 4126
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 1424  ax-7 1425  ax-gen 1426  ax-ie1 1470  ax-ie2 1471  ax-8 1483  ax-10 1484  ax-11 1485  ax-i12 1486  ax-bndl 1487  ax-4 1488  ax-14 1493  ax-17 1507  ax-i9 1511  ax-ial 1515  ax-i5r 1516  ax-ext 2122  ax-sep 4054  ax-nul 4062  ax-pow 4106
This theorem depends on definitions:  df-bi 116  df-dc 821  df-tru 1335  df-nf 1438  df-sb 1737  df-clab 2127  df-cleq 2133  df-clel 2136  df-nfc 2271  df-rab 2426  df-v 2691  df-dif 3078  df-in 3082  df-ss 3089  df-nul 3369  df-pw 3517  df-sn 3538  df-exmid 4127
This theorem is referenced by: (None)
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