Theorem pm5.31 360

Description: Theorem *5.31 of [WhiteheadRussell] p. 125.

Assertion

Ref	Expression
pm5.31	|- ((ch /\ (ph -> ps)) -> (ph -> (ps /\ ch)))

Proof of Theorem pm5.31

Step	Hyp	Ref	Expression
1		pm3.21 284	. . 3 |- (ch -> (ps -> (ps /\ ch)))
2	1	imim2d 25	. 2 |- (ch -> ((ph -> ps) -> (ph -> (ps /\ ch))))
3	2	imp 350	1 |- ((ch /\ (ph -> ps)) -> (ph -> (ps /\ ch)))

Syntax hints:   -> wi 3   /\ wa 223

This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7

This theorem depends on definitions:  df-bi 147  df-an 225

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