Description: Existential uniqueness implies uniqueness through reverse implication. (Contributed by NM, 22-Apr-1995)
Ref | Expression | ||
---|---|---|---|
Assertion | euimmo | |- ( A. x ( ph -> ps ) -> ( E! x ps -> E* x ph ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | eumo | |- ( E! x ps -> E* x ps ) |
|
2 | moim | |- ( A. x ( ph -> ps ) -> ( E* x ps -> E* x ph ) ) |
|
3 | 1 2 | syl5 | |- ( A. x ( ph -> ps ) -> ( E! x ps -> E* x ph ) ) |