Theorem pm2.42 772

Description: Theorem *2.42 of [WhiteheadRussell] p. 106. (Contributed by NM, 3-Jan-2005.)

Assertion

Ref	Expression
pm2.42	|- ( ( -. ph \/ ( ph -> ps ) ) -> ( ph -> ps ) )

Proof of Theorem pm2.42

Step	Hyp	Ref	Expression
1		pm2.21 612	. 2 |- ( -. ph -> ( ph -> ps ) )
2		id 19	. 2 |- ( ( ph -> ps ) -> ( ph -> ps ) )
3	1, 2	jaoi 711	1 |- ( ( -. ph \/ ( ph -> ps ) ) -> ( ph -> ps ) )

Syntax hints:   -. wn 3   -> wi 4   \/ wo 703

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in2 610  ax-io 704

This theorem depends on definitions:  df-bi 116

This theorem is referenced by: (None)