Theorem ceqsalv 2711

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 1508	. 2 |- F/ x ps
2		ceqsalv.1	. 2 |- A e. _V
3		ceqsalv.2	. 2 |- ( x = A -> ( ph <-> ps ) )
4	1, 2, 3	ceqsal 2710	1 |- ( A. x ( x = A -> ph ) <-> ps )

Syntax hints:   -> wi 4   <-> wb 104   A.wal 1329   = wceq 1331   e. wcel 1480   _Vcvv 2681

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 1423  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-4 1487  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-ext 2119

This theorem depends on definitions:  df-bi 116  df-nf 1437  df-sb 1736  df-clab 2124  df-cleq 2130  df-clel 2133  df-v 2683

This theorem is referenced by:  gencbval  2729  clel2  2813  clel4  2816  reu8  2875  raliunxp  4675  fv3  5437