Description: Distribute antecedent and add another. (Contributed by RP, 24-Dec-2019)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | rp-7frege | |- ( ( ph -> ( ps -> ch ) ) -> ( th -> ( ( ph -> ps ) -> ( ph -> ch ) ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ax-frege2 | |- ( ( ph -> ( ps -> ch ) ) -> ( ( ph -> ps ) -> ( ph -> ch ) ) ) |
|
| 2 | rp-frege24 | |- ( ( ( ph -> ( ps -> ch ) ) -> ( ( ph -> ps ) -> ( ph -> ch ) ) ) -> ( ( ph -> ( ps -> ch ) ) -> ( th -> ( ( ph -> ps ) -> ( ph -> ch ) ) ) ) ) |
|
| 3 | 1 2 | ax-mp | |- ( ( ph -> ( ps -> ch ) ) -> ( th -> ( ( ph -> ps ) -> ( ph -> ch ) ) ) ) |