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Theorem bj-stal 13630
Description: The universal quantification of a stable formula is stable. See bj-stim 13627 for implication, stabnot 823 for negation, and bj-stan 13628 for conjunction. (Contributed by BJ, 24-Nov-2023.)
Assertion
Ref Expression
bj-stal  |-  ( A. xSTAB  ph 
-> STAB  A. x ph )

Proof of Theorem bj-stal
StepHypRef Expression
1 nnal 1637 . . 3  |-  ( -. 
-.  A. x ph  ->  A. x  -.  -.  ph )
2 alim 1445 . . 3  |-  ( A. x ( -.  -.  ph 
->  ph )  ->  ( A. x  -.  -.  ph  ->  A. x ph )
)
31, 2syl5 32 . 2  |-  ( A. x ( -.  -.  ph 
->  ph )  ->  ( -.  -.  A. x ph  ->  A. x ph )
)
4 df-stab 821 . . 3  |-  (STAB  ph  <->  ( -.  -.  ph  ->  ph ) )
54albii 1458 . 2  |-  ( A. xSTAB  ph  <->  A. x ( -.  -.  ph 
->  ph ) )
6 df-stab 821 . 2  |-  (STAB  A. x ph 
<->  ( -.  -.  A. x ph  ->  A. x ph ) )
73, 5, 63imtr4i 200 1  |-  ( A. xSTAB  ph 
-> STAB  A. x ph )
Colors of variables: wff set class
Syntax hints:   -. wn 3    -> wi 4  STAB wstab 820   A.wal 1341
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-5 1435  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-4 1498  ax-17 1514  ax-ial 1522
This theorem depends on definitions:  df-bi 116  df-stab 821  df-tru 1346  df-fal 1349  df-nf 1449
This theorem is referenced by: (None)
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