Theorem ee220

Description: e220 without virtual deductions. (Contributed by Alan Sare, 12-Jul-2011) (Proof modification is discouraged.) (New usage is discouraged.)

	Ref	Expression
Hypotheses	ee220.1	|- ( ph -> ( ps -> ch ) )
	ee220.2	|- ( ph -> ( ps -> th ) )
	ee220.3	|- ta
	ee220.4	|- ( ch -> ( th -> ( ta -> et ) ) )
Assertion	ee220	|- ( ph -> ( ps -> et ) )

Proof

Step	Hyp	Ref	Expression
1		ee220.1	|- ( ph -> ( ps -> ch ) )
2		ee220.2	|- ( ph -> ( ps -> th ) )
3		ee220.3	|- ta
4		ee220.4	|- ( ch -> ( th -> ( ta -> et ) ) )
5	3	2a1i	|- ( ph -> ( ps -> ta ) )
6	1 2 5 4	ee222	|- ( ph -> ( ps -> et ) )