Metamath Proof Explorer

Theorem pm5.11g

Description: A general instance of Theorem *5.11 of WhiteheadRussell p. 123. (Contributed by NM, 3-Jan-2005)

Ref Expression
Assertion pm5.11g 
|- ( ( ph -> ps ) \/ ( -. ph -> ch ) )

Proof

Step Hyp Ref Expression
1 pm2.5g 
 |-  ( -. ( ph -> ps ) -> ( -. ph -> ch ) )
2 1 orri 
 |-  ( ( ph -> ps ) \/ ( -. ph -> ch ) )