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Theorem exmid0el 4336
Description: Excluded middle is equivalent to decidability of  (/) being an element of an arbitrary set. (Contributed by Jim Kingdon, 18-Jun-2022.)
Assertion
Ref Expression
exmid0el  |-  (EXMID  <->  A. xDECID  (/)  e.  x
)

Proof of Theorem exmid0el
StepHypRef Expression
1 exmidexmid 4328 . . 3  |-  (EXMID  -> DECID  (/)  e.  x )
21alrimiv 1927 . 2  |-  (EXMID  ->  A. xDECID  (/)  e.  x
)
3 ax-1 6 . . . 4  |-  (DECID  (/)  e.  x  ->  ( x  C_  { (/) }  -> DECID  (/) 
e.  x ) )
43alimi 1508 . . 3  |-  ( A. xDECID  (/) 
e.  x  ->  A. x
( x  C_  { (/) }  -> DECID  (/) 
e.  x ) )
5 df-exmid 4327 . . 3  |-  (EXMID  <->  A. x
( x  C_  { (/) }  -> DECID  (/) 
e.  x ) )
64, 5sylibr 134 . 2  |-  ( A. xDECID  (/) 
e.  x  -> EXMID )
72, 6impbii 126 1  |-  (EXMID  <->  A. xDECID  (/)  e.  x
)
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 105  DECID wdc 846   A.wal 1400    e. wcel 2209    C_ wss 3220   (/)c0 3520   {csn 3705  EXMIDwem 4326
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 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 4244  ax-nul 4254  ax-pow 4306
This theorem 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 3687  df-sn 3711  df-exmid 4327
This theorem is referenced by:  exmidel  4337
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