Description: Commutation in antecedent. Swap 1st and 2nd. (Contributed by NM, 28-Jan-1996) (Proof shortened by Andrew Salmon, 13-May-2011) (Proof shortened by Wolf Lammen, 22-Jun-2022)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | 3exp.1 | |- ( ( ph /\ ps /\ ch ) -> th ) |
|
| Assertion | 3com12 | |- ( ( ps /\ ph /\ ch ) -> th ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 3exp.1 | |- ( ( ph /\ ps /\ ch ) -> th ) |
|
| 2 | 1 | 3exp | |- ( ph -> ( ps -> ( ch -> th ) ) ) |
| 3 | 2 | 3imp21 | |- ( ( ps /\ ph /\ ch ) -> th ) |