Theorem bj-nnfeai

Description: Nonfreeness implies the equivalent of ax5ea , inference form. (Contributed by BJ, 22-Sep-2024)

	Ref	Expression
Hypothesis	bj-nnfeai.1	|- F// x ph
Assertion	bj-nnfeai	|- ( E. x ph -> A. x ph )

Proof

Step	Hyp	Ref	Expression
1		bj-nnfeai.1	|- F// x ph
2		bj-nnfea	|- ( F// x ph -> ( E. x ph -> A. x ph ) )
3	1 2	ax-mp	|- ( E. x ph -> A. x ph )