Theorem abcdta

Description: Given (((a and b) and c) and d), there exists a proof for a. (Contributed by Jarvin Udandy, 3-Sep-2016)

	Ref	Expression
Hypothesis	abcdta.1	|- ( ( ( ph /\ ps ) /\ ch ) /\ th )
Assertion	abcdta	|- ph

Proof

Step	Hyp	Ref	Expression
1		abcdta.1	|- ( ( ( ph /\ ps ) /\ ch ) /\ th )
2	1	simpli	|- ( ( ph /\ ps ) /\ ch )
3	2	simpli	|- ( ph /\ ps )
4	3	simpli	|- ph