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Theorem pw1fin 7221
Description: Excluded middle is equivalent to the power set of  1o being finite. (Contributed by SN and Jim Kingdon, 7-Aug-2024.)
Assertion
Ref Expression
pw1fin  |-  (EXMID  <->  ~P 1o  e.  Fin )

Proof of Theorem pw1fin
StepHypRef Expression
1 exmidpweq 7220 . . . 4  |-  (EXMID  <->  ~P 1o  =  2o )
21biimpi 120 . . 3  |-  (EXMID  ->  ~P 1o  =  2o )
3 2onn 6798 . . . 4  |-  2o  e.  om
4 nnfi 7178 . . . 4  |-  ( 2o  e.  om  ->  2o  e.  Fin )
53, 4ax-mp 5 . . 3  |-  2o  e.  Fin
62, 5eqeltrdi 2329 . 2  |-  (EXMID  ->  ~P 1o  e.  Fin )
7 df1o2 6705 . . . . . 6  |-  1o  =  { (/) }
87sseq2i 3275 . . . . 5  |-  ( x 
C_  1o  <->  x  C_  { (/) } )
9 velpw 3695 . . . . . 6  |-  ( x  e.  ~P 1o  <->  x  C_  1o )
10 1oex 6699 . . . . . . . 8  |-  1o  e.  _V
1110pwid 3707 . . . . . . 7  |-  1o  e.  ~P 1o
12 fidceq 7175 . . . . . . 7  |-  ( ( ~P 1o  e.  Fin  /\  x  e.  ~P 1o  /\  1o  e.  ~P 1o )  -> DECID 
x  =  1o )
1311, 12mp3an3 1367 . . . . . 6  |-  ( ( ~P 1o  e.  Fin  /\  x  e.  ~P 1o )  -> DECID 
x  =  1o )
149, 13sylan2br 288 . . . . 5  |-  ( ( ~P 1o  e.  Fin  /\  x  C_  1o )  -> DECID  x  =  1o )
158, 14sylan2br 288 . . . 4  |-  ( ( ~P 1o  e.  Fin  /\  x  C_  { (/) } )  -> DECID 
x  =  1o )
167eqeq2i 2249 . . . . 5  |-  ( x  =  1o  <->  x  =  { (/) } )
1716dcbii 852 . . . 4  |-  (DECID  x  =  1o  <-> DECID  x  =  { (/) } )
1815, 17sylib 122 . . 3  |-  ( ( ~P 1o  e.  Fin  /\  x  C_  { (/) } )  -> DECID 
x  =  { (/) } )
1918exmid1dc 4339 . 2  |-  ( ~P 1o  e.  Fin  -> EXMID )
206, 19impbii 126 1  |-  (EXMID  <->  ~P 1o  e.  Fin )
Colors of variables:    wff set class
This proof depends on syntax axioms:    /\ wa 104    <-> wb 105  DECID wdc 846    = wceq 1402    e. wcel 2209    C_ wss 3220   (/)c0 3520   ~Pcpw 3688   {csn 3709  EXMIDwem 4333   omcom 4739   1oc1o 6684   2oc2o 6685   Fincfn 7026
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 4251  ax-nul 4261  ax-pow 4313  ax-pr 4348  ax-un 4580  ax-setind 4686  ax-iinf 4737
This proof depends on definitions:  df-bi 117  df-dc 847  df-3or 1010  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-ral 2533  df-rex 2534  df-v 2823  df-sbc 3052  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-int 3971  df-br 4132  df-opab 4194  df-tr 4232  df-exmid 4334  df-id 4440  df-iord 4513  df-on 4515  df-suc 4518  df-iom 4740  df-xp 4782  df-rel 4783  df-cnv 4784  df-co 4785  df-dm 4786  df-rn 4787  df-res 4788  df-ima 4789  df-iota 5340  df-fun 5382  df-fn 5383  df-f 5384  df-f1 5385  df-fo 5386  df-f1o 5387  df-fv 5388  df-1o 6691  df-2o 6692  df-en 7027  df-fin 7029
This theorem is used by: (None)
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