Theorem exp53

Description: An exportation inference. (Contributed by Jeff Hankins, 30-Aug-2009)

	Ref	Expression
Hypothesis	exp53.1	|- ( ( ( ( ph /\ ps ) /\ ( ch /\ th ) ) /\ ta ) -> et )
Assertion	exp53	|- ( ph -> ( ps -> ( ch -> ( th -> ( ta -> et ) ) ) ) )

Proof

Step	Hyp	Ref	Expression
1		exp53.1	|- ( ( ( ( ph /\ ps ) /\ ( ch /\ th ) ) /\ ta ) -> et )
2	1	ex	|- ( ( ( ph /\ ps ) /\ ( ch /\ th ) ) -> ( ta -> et ) )
3	2	exp43	|- ( ph -> ( ps -> ( ch -> ( th -> ( ta -> et ) ) ) ) )