Description: An inference based on modus ponens. (Contributed by NM, 10-Apr-1994) (Proof shortened by Wolf Lammen, 19-Nov-2012)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | mpani.1 | |- ps |
|
| mpani.2 | |- ( ph -> ( ( ps /\ ch ) -> th ) ) |
||
| Assertion | mpani | |- ( ph -> ( ch -> th ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | mpani.1 | |- ps |
|
| 2 | mpani.2 | |- ( ph -> ( ( ps /\ ch ) -> th ) ) |
|
| 3 | 1 | a1i | |- ( ph -> ps ) |
| 4 | 3 2 | mpand | |- ( ph -> ( ch -> th ) ) |