ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  regexmidlem1 Unicode version

Theorem regexmidlem1 4448
Description: Lemma for regexmid 4450. If  A has a minimal element, excluded middle follows. (Contributed by Jim Kingdon, 3-Sep-2019.)
Hypothesis
Ref Expression
regexmidlemm.a  |-  A  =  { x  e.  { (/)
,  { (/) } }  |  ( x  =  { (/) }  \/  (
x  =  (/)  /\  ph ) ) }
Assertion
Ref Expression
regexmidlem1  |-  ( E. y ( y  e.  A  /\  A. z
( z  e.  y  ->  -.  z  e.  A ) )  -> 
( ph  \/  -.  ph ) )
Distinct variable groups:    y, A, z    ph, x, y
Allowed substitution hints:    ph( z)    A( x)

Proof of Theorem regexmidlem1
StepHypRef Expression
1 eqeq1 2146 . . . . . . 7  |-  ( x  =  y  ->  (
x  =  { (/) }  <-> 
y  =  { (/) } ) )
2 eqeq1 2146 . . . . . . . 8  |-  ( x  =  y  ->  (
x  =  (/)  <->  y  =  (/) ) )
32anbi1d 460 . . . . . . 7  |-  ( x  =  y  ->  (
( x  =  (/)  /\ 
ph )  <->  ( y  =  (/)  /\  ph )
) )
41, 3orbi12d 782 . . . . . 6  |-  ( x  =  y  ->  (
( x  =  { (/)
}  \/  ( x  =  (/)  /\  ph )
)  <->  ( y  =  { (/) }  \/  (
y  =  (/)  /\  ph ) ) ) )
5 regexmidlemm.a . . . . . 6  |-  A  =  { x  e.  { (/)
,  { (/) } }  |  ( x  =  { (/) }  \/  (
x  =  (/)  /\  ph ) ) }
64, 5elrab2 2843 . . . . 5  |-  ( y  e.  A  <->  ( y  e.  { (/) ,  { (/) } }  /\  ( y  =  { (/) }  \/  ( y  =  (/)  /\ 
ph ) ) ) )
76simprbi 273 . . . 4  |-  ( y  e.  A  ->  (
y  =  { (/) }  \/  ( y  =  (/)  /\  ph ) ) )
8 0ex 4055 . . . . . . . . 9  |-  (/)  e.  _V
98snid 3556 . . . . . . . 8  |-  (/)  e.  { (/)
}
10 eleq2 2203 . . . . . . . 8  |-  ( y  =  { (/) }  ->  (
(/)  e.  y  <->  (/)  e.  { (/)
} ) )
119, 10mpbiri 167 . . . . . . 7  |-  ( y  =  { (/) }  ->  (/)  e.  y )
12 eleq1 2202 . . . . . . . . 9  |-  ( z  =  (/)  ->  ( z  e.  y  <->  (/)  e.  y ) )
13 eleq1 2202 . . . . . . . . . 10  |-  ( z  =  (/)  ->  ( z  e.  A  <->  (/)  e.  A
) )
1413notbid 656 . . . . . . . . 9  |-  ( z  =  (/)  ->  ( -.  z  e.  A  <->  -.  (/)  e.  A
) )
1512, 14imbi12d 233 . . . . . . . 8  |-  ( z  =  (/)  ->  ( ( z  e.  y  ->  -.  z  e.  A
)  <->  ( (/)  e.  y  ->  -.  (/)  e.  A
) ) )
168, 15spcv 2779 . . . . . . 7  |-  ( A. z ( z  e.  y  ->  -.  z  e.  A )  ->  ( (/) 
e.  y  ->  -.  (/) 
e.  A ) )
1711, 16syl5com 29 . . . . . 6  |-  ( y  =  { (/) }  ->  ( A. z ( z  e.  y  ->  -.  z  e.  A )  ->  -.  (/)  e.  A ) )
188prid1 3629 . . . . . . . . . 10  |-  (/)  e.  { (/)
,  { (/) } }
19 eqeq1 2146 . . . . . . . . . . . 12  |-  ( x  =  (/)  ->  ( x  =  { (/) }  <->  (/)  =  { (/)
} ) )
20 eqeq1 2146 . . . . . . . . . . . . 13  |-  ( x  =  (/)  ->  ( x  =  (/)  <->  (/)  =  (/) ) )
2120anbi1d 460 . . . . . . . . . . . 12  |-  ( x  =  (/)  ->  ( ( x  =  (/)  /\  ph ) 
<->  ( (/)  =  (/)  /\  ph ) ) )
2219, 21orbi12d 782 . . . . . . . . . . 11  |-  ( x  =  (/)  ->  ( ( x  =  { (/) }  \/  ( x  =  (/)  /\  ph ) )  <-> 
( (/)  =  { (/) }  \/  ( (/)  =  (/)  /\ 
ph ) ) ) )
2322, 5elrab2 2843 . . . . . . . . . 10  |-  ( (/)  e.  A  <->  ( (/)  e.  { (/)
,  { (/) } }  /\  ( (/)  =  { (/)
}  \/  ( (/)  =  (/)  /\  ph )
) ) )
2418, 23mpbiran 924 . . . . . . . . 9  |-  ( (/)  e.  A  <->  ( (/)  =  { (/)
}  \/  ( (/)  =  (/)  /\  ph )
) )
25 pm2.46 728 . . . . . . . . 9  |-  ( -.  ( (/)  =  { (/)
}  \/  ( (/)  =  (/)  /\  ph )
)  ->  -.  ( (/)  =  (/)  /\  ph )
)
2624, 25sylnbi 667 . . . . . . . 8  |-  ( -.  (/)  e.  A  ->  -.  ( (/)  =  (/)  /\  ph ) )
27 eqid 2139 . . . . . . . . 9  |-  (/)  =  (/)
2827biantrur 301 . . . . . . . 8  |-  ( ph  <->  (
(/)  =  (/)  /\  ph ) )
2926, 28sylnibr 666 . . . . . . 7  |-  ( -.  (/)  e.  A  ->  -.  ph )
3029olcd 723 . . . . . 6  |-  ( -.  (/)  e.  A  ->  ( ph  \/  -.  ph )
)
3117, 30syl6 33 . . . . 5  |-  ( y  =  { (/) }  ->  ( A. z ( z  e.  y  ->  -.  z  e.  A )  ->  ( ph  \/  -.  ph ) ) )
32 orc 701 . . . . . . 7  |-  ( ph  ->  ( ph  \/  -.  ph ) )
3332adantl 275 . . . . . 6  |-  ( ( y  =  (/)  /\  ph )  ->  ( ph  \/  -.  ph ) )
3433a1d 22 . . . . 5  |-  ( ( y  =  (/)  /\  ph )  ->  ( A. z
( z  e.  y  ->  -.  z  e.  A )  ->  ( ph  \/  -.  ph )
) )
3531, 34jaoi 705 . . . 4  |-  ( ( y  =  { (/) }  \/  ( y  =  (/)  /\  ph ) )  ->  ( A. z
( z  e.  y  ->  -.  z  e.  A )  ->  ( ph  \/  -.  ph )
) )
367, 35syl 14 . . 3  |-  ( y  e.  A  ->  ( A. z ( z  e.  y  ->  -.  z  e.  A )  ->  ( ph  \/  -.  ph )
) )
3736imp 123 . 2  |-  ( ( y  e.  A  /\  A. z ( z  e.  y  ->  -.  z  e.  A ) )  -> 
( ph  \/  -.  ph ) )
3837exlimiv 1577 1  |-  ( E. y ( y  e.  A  /\  A. z
( z  e.  y  ->  -.  z  e.  A ) )  -> 
( ph  \/  -.  ph ) )
Colors of variables: wff set class
Syntax hints:   -. wn 3    -> wi 4    /\ wa 103    \/ wo 697   A.wal 1329    = wceq 1331   E.wex 1468    e. wcel 1480   {crab 2420   (/)c0 3363   {csn 3527   {cpr 3528
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 603  ax-in2 604  ax-io 698  ax-5 1423  ax-7 1424  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-10 1483  ax-11 1484  ax-i12 1485  ax-bndl 1486  ax-4 1487  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2121  ax-nul 4054
This theorem depends on definitions:  df-bi 116  df-tru 1334  df-nf 1437  df-sb 1736  df-clab 2126  df-cleq 2132  df-clel 2135  df-nfc 2270  df-rab 2425  df-v 2688  df-dif 3073  df-un 3075  df-nul 3364  df-sn 3533  df-pr 3534
This theorem is referenced by:  regexmid  4450  nnregexmid  4534
  Copyright terms: Public domain W3C validator