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Theorem pw1fin 6971
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 6970 . . . 4  |-  (EXMID  <->  ~P 1o  =  2o )
21biimpi 120 . . 3  |-  (EXMID  ->  ~P 1o  =  2o )
3 2onn 6579 . . . 4  |-  2o  e.  om
4 nnfi 6933 . . . 4  |-  ( 2o  e.  om  ->  2o  e.  Fin )
53, 4ax-mp 5 . . 3  |-  2o  e.  Fin
62, 5eqeltrdi 2287 . 2  |-  (EXMID  ->  ~P 1o  e.  Fin )
7 df1o2 6487 . . . . . 6  |-  1o  =  { (/) }
87sseq2i 3210 . . . . 5  |-  ( x 
C_  1o  <->  x  C_  { (/) } )
9 velpw 3612 . . . . . 6  |-  ( x  e.  ~P 1o  <->  x  C_  1o )
10 1oex 6482 . . . . . . . 8  |-  1o  e.  _V
1110pwid 3620 . . . . . . 7  |-  1o  e.  ~P 1o
12 fidceq 6930 . . . . . . 7  |-  ( ( ~P 1o  e.  Fin  /\  x  e.  ~P 1o  /\  1o  e.  ~P 1o )  -> DECID 
x  =  1o )
1311, 12mp3an3 1337 . . . . . 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 2207 . . . . 5  |-  ( x  =  1o  <->  x  =  { (/) } )
1716dcbii 841 . . . 4  |-  (DECID  x  =  1o  <-> DECID  x  =  { (/) } )
1815, 17sylib 122 . . 3  |-  ( ( ~P 1o  e.  Fin  /\  x  C_  { (/) } )  -> DECID 
x  =  { (/) } )
1918exmid1dc 4233 . 2  |-  ( ~P 1o  e.  Fin  -> EXMID )
206, 19impbii 126 1  |-  (EXMID  <->  ~P 1o  e.  Fin )
Colors of variables: wff set class
Syntax hints:    /\ wa 104    <-> wb 105  DECID wdc 835    = wceq 1364    e. wcel 2167    C_ wss 3157   (/)c0 3450   ~Pcpw 3605   {csn 3622  EXMIDwem 4227   omcom 4626   1oc1o 6467   2oc2o 6468   Fincfn 6799
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 615  ax-in2 616  ax-io 710  ax-5 1461  ax-7 1462  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-8 1518  ax-10 1519  ax-11 1520  ax-i12 1521  ax-bndl 1523  ax-4 1524  ax-17 1540  ax-i9 1544  ax-ial 1548  ax-i5r 1549  ax-13 2169  ax-14 2170  ax-ext 2178  ax-sep 4151  ax-nul 4159  ax-pow 4207  ax-pr 4242  ax-un 4468  ax-setind 4573  ax-iinf 4624
This theorem depends on definitions:  df-bi 117  df-dc 836  df-3or 981  df-3an 982  df-tru 1367  df-fal 1370  df-nf 1475  df-sb 1777  df-eu 2048  df-mo 2049  df-clab 2183  df-cleq 2189  df-clel 2192  df-nfc 2328  df-ne 2368  df-ral 2480  df-rex 2481  df-v 2765  df-sbc 2990  df-dif 3159  df-un 3161  df-in 3163  df-ss 3170  df-nul 3451  df-pw 3607  df-sn 3628  df-pr 3629  df-op 3631  df-uni 3840  df-int 3875  df-br 4034  df-opab 4095  df-tr 4132  df-exmid 4228  df-id 4328  df-iord 4401  df-on 4403  df-suc 4406  df-iom 4627  df-xp 4669  df-rel 4670  df-cnv 4671  df-co 4672  df-dm 4673  df-rn 4674  df-res 4675  df-ima 4676  df-iota 5219  df-fun 5260  df-fn 5261  df-f 5262  df-f1 5263  df-fo 5264  df-f1o 5265  df-fv 5266  df-1o 6474  df-2o 6475  df-en 6800  df-fin 6802
This theorem is referenced by: (None)
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