Description: Existential elimination rule of natural deduction. (Contributed by ML, 17-Jul-2020)
Ref | Expression | ||
---|---|---|---|
Hypotheses | exlimimd.1 | |- ( ph -> E. x ps ) |
|
exlimimd.2 | |- ( ph -> ( ps -> ch ) ) |
||
Assertion | exlimimd | |- ( ph -> ch ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | exlimimd.1 | |- ( ph -> E. x ps ) |
|
2 | exlimimd.2 | |- ( ph -> ( ps -> ch ) ) |
|
3 | 2 | imp | |- ( ( ph /\ ps ) -> ch ) |
4 | 1 3 | exlimddv | |- ( ph -> ch ) |