Metamath Proof Explorer

Theorem pm2.62

Description: Theorem *2.62 of WhiteheadRussell p. 107. (Contributed by NM, 3-Jan-2005) (Proof shortened by Wolf Lammen, 13-Dec-2013)

Ref Expression
Assertion pm2.62 
|- ( ( ph \/ ps ) -> ( ( ph -> ps ) -> ps ) )

Proof

Step Hyp Ref Expression
1 pm2.621 
 |-  ( ( ph -> ps ) -> ( ( ph \/ ps ) -> ps ) )
2 1 com12 
 |-  ( ( ph \/ ps ) -> ( ( ph -> ps ) -> ps ) )