Theorem com4l

Description: Commutation of antecedents. Rotate left. (Contributed by NM, 25-Apr-1994) (Proof shortened by Mel L. O'Cat, 15-Aug-2004)

	Ref	Expression
Hypothesis	com4.1	|- ( ph -> ( ps -> ( ch -> ( th -> ta ) ) ) )
Assertion	com4l	|- ( ps -> ( ch -> ( th -> ( ph -> ta ) ) ) )

Proof

Step	Hyp	Ref	Expression
1		com4.1	|- ( ph -> ( ps -> ( ch -> ( th -> ta ) ) ) )
2	1	com3l	|- ( ps -> ( ch -> ( ph -> ( th -> ta ) ) ) )
3	2	com34	|- ( ps -> ( ch -> ( th -> ( ph -> ta ) ) ) )