Theorem nfth 1475

Description: No variable is (effectively) free in a theorem. (Contributed by Mario Carneiro, 11-Aug-2016.)

Hypothesis

Ref	Expression
hbth.1	|- ph

Assertion

Ref	Expression
nfth	|- F/ x ph

Proof of Theorem nfth

Step	Hyp	Ref	Expression
1		hbth.1	. . 3 |- ph
2	1	hbth 1474	. 2 |- ( ph -> A. x ph )
3	2	nfi 1473	1 |- F/ x ph

Syntax hints:   F/wnf 1471

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-gen 1460

This theorem depends on definitions:  df-bi 117  df-nf 1472

This theorem is referenced by:  nftru  1477  nfequid  1713  sbt  1795  sbc2ie  3057  omsinds  4650