Description: Conjunction with implication. Compare Theorem *4.45 of WhiteheadRussell p. 119. (Contributed by NM, 17-May-1998)
Ref | Expression | ||
---|---|---|---|
Assertion | pm4.45im | |- ( ph <-> ( ph /\ ( ps -> ph ) ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ax-1 | |- ( ph -> ( ps -> ph ) ) |
|
2 | 1 | pm4.71i | |- ( ph <-> ( ph /\ ( ps -> ph ) ) ) |