Theorem ceqsalv 2756

Description: A representation of explicit substitution of a class for a variable, inferred from an implicit substitution hypothesis. (Contributed by NM, 18-Aug-1993.)

Hypotheses

Ref	Expression
ceqsalv.1	|- A e. _V
ceqsalv.2	|- ( x = A -> ( ph <-> ps ) )

Assertion

Ref	Expression
ceqsalv	|- ( A. x ( x = A -> ph ) <-> ps )

Distinct variable groups:   x, A   ps, x

Allowed substitution hint:   ph( x)

Proof of Theorem ceqsalv

Step	Hyp	Ref	Expression
1		nfv 1516	. 2 |- F/ x ps
2		ceqsalv.1	. 2 |- A e. _V
3		ceqsalv.2	. 2 |- ( x = A -> ( ph <-> ps ) )
4	1, 2, 3	ceqsal 2755	1 |- ( A. x ( x = A -> ph ) <-> ps )

Syntax hints:   -> wi 4   <-> wb 104   A.wal 1341   = wceq 1343   e. wcel 2136   _Vcvv 2726

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-5 1435  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-ext 2147

This theorem depends on definitions:  df-bi 116  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-v 2728

This theorem is referenced by:  gencbval  2774  clel2  2859  clel4  2862  reu8  2922  raliunxp  4745  fv3  5509