Metamath Proof Explorer

Theorem pm4.76

Description: Theorem *4.76 of WhiteheadRussell p. 121. (Contributed by NM, 3-Jan-2005)

Ref Expression
Assertion pm4.76 
|- ( ( ( ph -> ps ) /\ ( ph -> ch ) ) <-> ( ph -> ( ps /\ ch ) ) )

Proof

Step Hyp Ref Expression
1 jcab 
 |-  ( ( ph -> ( ps /\ ch ) ) <-> ( ( ph -> ps ) /\ ( ph -> ch ) ) )
2 1 bicomi 
 |-  ( ( ( ph -> ps ) /\ ( ph -> ch ) ) <-> ( ph -> ( ps /\ ch ) ) )