Theorem axc4i 1556

Description: Inference version of 19.21 1597. (Contributed by NM, 3-Jan-1993.)

Hypothesis

Ref	Expression
axc4i.1	|- ( A. x ph -> ps )

Assertion

Ref	Expression
axc4i	|- ( A. x ph -> A. x ps )

Proof of Theorem axc4i

Step	Hyp	Ref	Expression
1		nfa1 1555	. 2 |- F/ x A. x ph
2		axc4i.1	. 2 |- ( A. x ph -> ps )
3	1, 2	alrimi 1536	1 |- ( A. x ph -> A. x ps )

Syntax hints:   -> wi 4   A.wal 1362

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1461  ax-gen 1463  ax-4 1524  ax-ial 1548

This theorem depends on definitions:  df-bi 117  df-nf 1475

This theorem is referenced by:  nfabdw  2358