Theorem ee122

Description: e122 without virtual deductions. (Contributed by Alan Sare, 13-Jul-2011) (Proof modification is discouraged.) (New usage is discouraged.)

	Ref	Expression
Hypotheses	ee122.1	|- ( ph -> ps )
	ee122.2	|- ( ph -> ( ch -> th ) )
	ee122.3	|- ( ph -> ( ch -> ta ) )
	ee122.4	|- ( ps -> ( th -> ( ta -> et ) ) )
Assertion	ee122	|- ( ph -> ( ch -> et ) )

Proof

Step	Hyp	Ref	Expression
1		ee122.1	|- ( ph -> ps )
2		ee122.2	|- ( ph -> ( ch -> th ) )
3		ee122.3	|- ( ph -> ( ch -> ta ) )
4		ee122.4	|- ( ps -> ( th -> ( ta -> et ) ) )
5	1	a1d	|- ( ph -> ( ch -> ps ) )
6	5 2 3 4	ee222	|- ( ph -> ( ch -> et ) )