Theorem wl-com12 33258

Description: Inference that swaps (commutes) antecedents in an implication. Copy of com12 32 with a different proof. (Contributed by Wolf Lammen, 17-Dec-2018.) (New usage is discouraged.) (Proof modification is discouraged.)

Hypothesis

Ref	Expression
wl-com12.1	|- ( ph -> ( ps -> ch ) )

Assertion

Ref	Expression
wl-com12	|- ( ps -> ( ph -> ch ) )

Proof of Theorem wl-com12

Step	Hyp	Ref	Expression
1		wl-com12.1	. 2 |- ( ph -> ( ps -> ch ) )
2		wl-pm2.27 33257	. 2 |- ( ps -> ( ( ps -> ch ) -> ch ) )
3	1, 2	wl-syl5 33247	1 |- ( ps -> ( ph -> ch ) )

Syntax hints:   -> wi 4

This theorem was proved from axioms:  ax-mp 5  ax-luk1 33241  ax-luk2 33242  ax-luk3 33243

This theorem is referenced by:  wl-pm2.21  33259  wl-imim2  33262