Theorem syldc

Description: Syllogism deduction. Commuted form of syld . (Contributed by BJ, 25-Oct-2021)

	Ref	Expression
Hypotheses	syld.1	|- ( ph -> ( ps -> ch ) )
	syld.2	|- ( ph -> ( ch -> th ) )
Assertion	syldc	|- ( ps -> ( ph -> th ) )

Proof

Step	Hyp	Ref	Expression
1		syld.1	|- ( ph -> ( ps -> ch ) )
2		syld.2	|- ( ph -> ( ch -> th ) )
3	1 2	syld	|- ( ph -> ( ps -> th ) )
4	3	com12	|- ( ps -> ( ph -> th ) )