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Theorem reg3exmid 4539
Description: If any inhabited set satisfying df-wetr 4294 for  _E has a minimal element, excluded middle follows. (Contributed by Jim Kingdon, 3-Oct-2021.)
Hypothesis
Ref Expression
reg3exmid.1  |-  ( (  _E  We  z  /\  E. w  w  e.  z )  ->  E. x  e.  z  A. y  e.  z  x  C_  y
)
Assertion
Ref Expression
reg3exmid  |-  ( ph  \/  -.  ph )
Distinct variable groups:    ph, w, z    ph, x, y, z

Proof of Theorem reg3exmid
Dummy variable  u is distinct from all other variables.
StepHypRef Expression
1 eqid 2157 . . 3  |-  { u  e.  { (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) }  =  { u  e.  { (/) ,  { (/) } }  | 
( u  =  { (/)
}  \/  ( u  =  (/)  /\  ph )
) }
21regexmidlemm 4491 . 2  |-  E. w  w  e.  { u  e.  { (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) }
31reg3exmidlemwe 4538 . . 3  |-  _E  We  { u  e.  { (/) ,  { (/) } }  | 
( u  =  { (/)
}  \/  ( u  =  (/)  /\  ph )
) }
4 pp0ex 4150 . . . . 5  |-  { (/) ,  { (/) } }  e.  _V
54rabex 4108 . . . 4  |-  { u  e.  { (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) }  e.  _V
6 weeq2 4317 . . . . . 6  |-  ( z  =  { u  e. 
{ (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) }  ->  (  _E  We  z  <->  _E  We  { u  e.  { (/) ,  { (/) } }  | 
( u  =  { (/)
}  \/  ( u  =  (/)  /\  ph )
) } ) )
7 eleq2 2221 . . . . . . 7  |-  ( z  =  { u  e. 
{ (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) }  ->  ( w  e.  z  <->  w  e.  { u  e.  { (/) ,  { (/) } }  | 
( u  =  { (/)
}  \/  ( u  =  (/)  /\  ph )
) } ) )
87exbidv 1805 . . . . . 6  |-  ( z  =  { u  e. 
{ (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) }  ->  ( E. w  w  e.  z  <->  E. w  w  e. 
{ u  e.  { (/)
,  { (/) } }  |  ( u  =  { (/) }  \/  (
u  =  (/)  /\  ph ) ) } ) )
96, 8anbi12d 465 . . . . 5  |-  ( z  =  { u  e. 
{ (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) }  ->  ( (  _E  We  z  /\  E. w  w  e.  z )  <->  (  _E  We  { u  e.  { (/)
,  { (/) } }  |  ( u  =  { (/) }  \/  (
u  =  (/)  /\  ph ) ) }  /\  E. w  w  e.  {
u  e.  { (/) ,  { (/) } }  | 
( u  =  { (/)
}  \/  ( u  =  (/)  /\  ph )
) } ) ) )
10 raleq 2652 . . . . . 6  |-  ( z  =  { u  e. 
{ (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) }  ->  ( A. y  e.  z  x  C_  y  <->  A. y  e.  { u  e.  { (/)
,  { (/) } }  |  ( u  =  { (/) }  \/  (
u  =  (/)  /\  ph ) ) } x  C_  y ) )
1110rexeqbi1dv 2661 . . . . 5  |-  ( z  =  { u  e. 
{ (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) }  ->  ( E. x  e.  z 
A. y  e.  z  x  C_  y  <->  E. x  e.  { u  e.  { (/)
,  { (/) } }  |  ( u  =  { (/) }  \/  (
u  =  (/)  /\  ph ) ) } A. y  e.  { u  e.  { (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) } x  C_  y ) )
129, 11imbi12d 233 . . . 4  |-  ( z  =  { u  e. 
{ (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) }  ->  ( ( (  _E  We  z  /\  E. w  w  e.  z )  ->  E. x  e.  z  A. y  e.  z  x  C_  y )  <->  ( (  _E  We  { u  e. 
{ (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) }  /\  E. w  w  e.  {
u  e.  { (/) ,  { (/) } }  | 
( u  =  { (/)
}  \/  ( u  =  (/)  /\  ph )
) } )  ->  E. x  e.  { u  e.  { (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) } A. y  e.  { u  e.  { (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) } x  C_  y ) ) )
13 reg3exmid.1 . . . 4  |-  ( (  _E  We  z  /\  E. w  w  e.  z )  ->  E. x  e.  z  A. y  e.  z  x  C_  y
)
145, 12, 13vtocl 2766 . . 3  |-  ( (  _E  We  { u  e.  { (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) }  /\  E. w  w  e.  {
u  e.  { (/) ,  { (/) } }  | 
( u  =  { (/)
}  \/  ( u  =  (/)  /\  ph )
) } )  ->  E. x  e.  { u  e.  { (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) } A. y  e.  { u  e.  { (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) } x  C_  y )
153, 14mpan 421 . 2  |-  ( E. w  w  e.  {
u  e.  { (/) ,  { (/) } }  | 
( u  =  { (/)
}  \/  ( u  =  (/)  /\  ph )
) }  ->  E. x  e.  { u  e.  { (/)
,  { (/) } }  |  ( u  =  { (/) }  \/  (
u  =  (/)  /\  ph ) ) } A. y  e.  { u  e.  { (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) } x  C_  y )
161reg2exmidlema 4493 . 2  |-  ( E. x  e.  { u  e.  { (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) } A. y  e.  { u  e.  { (/) ,  { (/) } }  |  ( u  =  { (/) }  \/  ( u  =  (/)  /\  ph ) ) } x  C_  y  ->  ( ph  \/  -.  ph ) )
172, 15, 16mp2b 8 1  |-  ( ph  \/  -.  ph )
Colors of variables: wff set class
Syntax hints:   -. wn 3    -> wi 4    /\ wa 103    \/ wo 698    = wceq 1335   E.wex 1472    e. wcel 2128   A.wral 2435   E.wrex 2436   {crab 2439    C_ wss 3102   (/)c0 3394   {csn 3560   {cpr 3561    _E cep 4247    We wwe 4290
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 1427  ax-7 1428  ax-gen 1429  ax-ie1 1473  ax-ie2 1474  ax-8 1484  ax-10 1485  ax-11 1486  ax-i12 1487  ax-bndl 1489  ax-4 1490  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-14 2131  ax-ext 2139  ax-sep 4082  ax-nul 4090  ax-pow 4135  ax-pr 4169  ax-setind 4496
This theorem depends on definitions:  df-bi 116  df-3an 965  df-tru 1338  df-nf 1441  df-sb 1743  df-eu 2009  df-mo 2010  df-clab 2144  df-cleq 2150  df-clel 2153  df-nfc 2288  df-ne 2328  df-ral 2440  df-rex 2441  df-rab 2444  df-v 2714  df-dif 3104  df-un 3106  df-in 3108  df-ss 3115  df-nul 3395  df-pw 3545  df-sn 3566  df-pr 3567  df-op 3569  df-br 3966  df-opab 4026  df-eprel 4249  df-frfor 4291  df-frind 4292  df-wetr 4294
This theorem is referenced by: (None)
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