Description: The at-most-one quantifier reverses implication, deduction form. (Contributed by Thierry Arnoux, 25-Feb-2017)
Ref | Expression | ||
---|---|---|---|
Hypothesis | moimdv.1 | |- ( ph -> ( ps -> ch ) ) |
|
Assertion | moimdv | |- ( ph -> ( E* x ch -> E* x ps ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | moimdv.1 | |- ( ph -> ( ps -> ch ) ) |
|
2 | 1 | alrimiv | |- ( ph -> A. x ( ps -> ch ) ) |
3 | moim | |- ( A. x ( ps -> ch ) -> ( E* x ch -> E* x ps ) ) |
|
4 | 2 3 | syl | |- ( ph -> ( E* x ch -> E* x ps ) ) |