Theorem drsb2 2378

Description: Formula-building lemma for use with the Distinctor Reduction Theorem. Part of Theorem 9.4 of [Megill] p. 448 (p. 16 of preprint). (Contributed by NM, 27-Feb-2005.)

Assertion

Ref	Expression
drsb2	|- ( A. x x = y -> ( [ x / z ] ph <-> [ y / z ] ph ) )

Proof of Theorem drsb2

Step	Hyp	Ref	Expression
1		sbequ 2376	. 2 |- ( x = y -> ( [ x / z ] ph <-> [ y / z ] ph ) )
2	1	sps 2055	1 |- ( A. x x = y -> ( [ x / z ] ph <-> [ y / z ] ph ) )

Syntax hints:   -> wi 4   <-> wb 196   A.wal 1481   [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  ax-13 2246

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:  sbcom3  2411  sbal2  2461