Description: Closed form of stdpc5 . (Possible to place it before 19.21t and use it to prove 19.21t ). (Contributed by BJ, 15-Sep-2018) (Proof modification is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | stdpc5t | |- ( F/ x ph -> ( A. x ( ph -> ps ) -> ( ph -> A. x ps ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | nf5r | |- ( F/ x ph -> ( ph -> A. x ph ) ) |
|
| 2 | alim | |- ( A. x ( ph -> ps ) -> ( A. x ph -> A. x ps ) ) |
|
| 3 | 1 2 | syl9 | |- ( F/ x ph -> ( A. x ( ph -> ps ) -> ( ph -> A. x ps ) ) ) |