Theorem pm2.63 763

Description: Theorem *2.63 of [WhiteheadRussell] p. 107. (Contributed by NM, 3-Jan-2005.)

Assertion

Ref	Expression
pm2.63	|- ((ph \/ ps) -> ((-. ph \/ ps) -> ps))

Proof of Theorem pm2.63

Step	Hyp	Ref	Expression
1		pm2.53 362	. 2 |- ((ph \/ ps) -> (-. ph -> ps))
2		idd 21	. 2 |- ((ph \/ ps) -> (ps -> ps))
3	1, 2	jaod 369	1 |- ((ph \/ ps) -> ((-. ph \/ ps) -> ps))

This proof depends on syntax axioms:  -. wn 3   -> wi 4   \/ wo 357

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8

This proof depends on definitions:  df-bi 177  df-or 359

This theorem is used by: (None)