Description: Add a conjunct to left of antecedent and consequent in a deduction. (Contributed by NM, 14-May-1993)
Ref | Expression | ||
---|---|---|---|
Hypothesis | anim1d.1 | |- ( ph -> ( ps -> ch ) ) |
|
Assertion | anim2d | |- ( ph -> ( ( th /\ ps ) -> ( th /\ ch ) ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | anim1d.1 | |- ( ph -> ( ps -> ch ) ) |
|
2 | idd | |- ( ph -> ( th -> th ) ) |
|
3 | 2 1 | anim12d | |- ( ph -> ( ( th /\ ps ) -> ( th /\ ch ) ) ) |