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Theorem exmid0el 4294
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 4286 . . 3  |-  (EXMID  -> DECID  (/)  e.  x )
21alrimiv 1922 . 2  |-  (EXMID  ->  A. xDECID  (/)  e.  x
)
3 ax-1 6 . . . 4  |-  (DECID  (/)  e.  x  ->  ( x  C_  { (/) }  -> DECID  (/) 
e.  x ) )
43alimi 1503 . . 3  |-  ( A. xDECID  (/) 
e.  x  ->  A. x
( x  C_  { (/) }  -> DECID  (/) 
e.  x ) )
5 df-exmid 4285 . . 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 841   A.wal 1395    e. wcel 2202    C_ wss 3200   (/)c0 3494   {csn 3669  EXMIDwem 4284
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 619  ax-in2 620  ax-io 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-14 2205  ax-ext 2213  ax-sep 4207  ax-nul 4215  ax-pow 4264
This theorem depends on definitions:  df-bi 117  df-dc 842  df-tru 1400  df-nf 1509  df-sb 1811  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-rab 2519  df-v 2804  df-dif 3202  df-in 3206  df-ss 3213  df-nul 3495  df-pw 3654  df-sn 3675  df-exmid 4285
This theorem is referenced by:  exmidel  4295
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