Description: Restricted quantifier version of one direction of 19.36 . (Contributed by Glauco Siliprandi, 23-Oct-2021)
Ref | Expression | ||
---|---|---|---|
Hypothesis | r19.36vf.1 | |- F/ x ps |
|
Assertion | r19.36vf | |- ( E. x e. A ( ph -> ps ) -> ( A. x e. A ph -> ps ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | r19.36vf.1 | |- F/ x ps |
|
2 | r19.35 | |- ( E. x e. A ( ph -> ps ) <-> ( A. x e. A ph -> E. x e. A ps ) ) |
|
3 | idd | |- ( x e. A -> ( ps -> ps ) ) |
|
4 | 1 3 | rexlimi | |- ( E. x e. A ps -> ps ) |
5 | 4 | imim2i | |- ( ( A. x e. A ph -> E. x e. A ps ) -> ( A. x e. A ph -> ps ) ) |
6 | 2 5 | sylbi | |- ( E. x e. A ( ph -> ps ) -> ( A. x e. A ph -> ps ) ) |