Theorem pm3.31 260

Description: Theorem *3.31 (Imp) of [WhiteheadRussell] p. 112. (Contributed by NM, 3-Jan-2005.) (Proof shortened by Wolf Lammen, 24-Mar-2013.)

Assertion

Ref	Expression
pm3.31	|- ( ( ph -> ( ps -> ch ) ) -> ( ( ph /\ ps ) -> ch ) )

Proof of Theorem pm3.31

Step	Hyp	Ref	Expression
1		id 19	. 2 |- ( ( ph -> ( ps -> ch ) ) -> ( ph -> ( ps -> ch ) ) )
2	1	impd 252	1 |- ( ( ph -> ( ps -> ch ) ) -> ( ( ph /\ ps ) -> ch ) )

Syntax hints:   -> wi 4   /\ wa 103

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106

This theorem is referenced by:  impexp  261  imp5a  356  equsexd  1722  mo3h  2072  rexim  2564  peano5  4582  issref  4993  bj-indind  13967