Theorem pm2.6 133

Description: Theorem *2.6 of [WhiteheadRussell] p. 107.

Assertion

Ref	Expression
pm2.6	|- ((-. ph -> ps) -> ((ph -> ps) -> ps))

Proof of Theorem pm2.6

Step	Hyp	Ref	Expression
1		pm2.61 124	. 2 |- ((ph -> ps) -> ((-. ph -> ps) -> ps))
2	1	com12 11	1 |- ((-. ph -> ps) -> ((ph -> ps) -> ps))

Syntax hints:  -. wn 2   -> wi 3

This theorem is referenced by:  dfor2 229

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

Copyright terms: Public domain