Theorem bnj1232

Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

	Ref	Expression
Hypothesis	bnj1232.1	|- ( ph <-> ( ps /\ ch /\ th /\ ta ) )
Assertion	bnj1232	|- ( ph -> ps )

Proof

Step	Hyp	Ref	Expression
1		bnj1232.1	|- ( ph <-> ( ps /\ ch /\ th /\ ta ) )
2		bnj642	|- ( ( ps /\ ch /\ th /\ ta ) -> ps )
3	1 2	sylbi	|- ( ph -> ps )