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Theorem bj-sb4v 32757
Description: Version of sb4 2356 with a dv condition, which does not require ax-13 2246. (Contributed by BJ, 23-Jun-2019.) Together with bj-sb2v 32753, this allosw to remove ax-13 2246 from sb6 2429 (see bj-sb6 32767). Note that this subsumes the version of sb4b 2358 with a dv condition. (Proof modification is discouraged.)
Assertion
Ref Expression
bj-sb4v  |-  ( [ y  /  x ] ph  ->  A. x ( x  =  y  ->  ph )
)
Distinct variable group:    x, y
Allowed substitution hints:    ph( x, y)

Proof of Theorem bj-sb4v
StepHypRef Expression
1 sb1 1883 . 2  |-  ( [ y  /  x ] ph  ->  E. x ( x  =  y  /\  ph ) )
2 sb56 2150 . 2  |-  ( E. x ( x  =  y  /\  ph )  <->  A. x ( x  =  y  ->  ph ) )
31, 2sylib 208 1  |-  ( [ y  /  x ] ph  ->  A. x ( x  =  y  ->  ph )
)
Colors of variables: wff setvar class
Syntax hints:    -> wi 4    /\ wa 384   A.wal 1481   E.wex 1704   [wsb 1880
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-10 2019  ax-12 2047
This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-ex 1705  df-nf 1710  df-sb 1881
This theorem is referenced by:  bj-hbs1  32758
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