Description: Restricted existential specialization, using implicit substitution. Variant of rspcedv . (Contributed by AV, 27-Nov-2019)
Ref | Expression | ||
---|---|---|---|
Hypotheses | rspcedvd.1 | |- ( ph -> A e. B ) |
|
rspcedvd.2 | |- ( ( ph /\ x = A ) -> ( ps <-> ch ) ) |
||
rspcedvd.3 | |- ( ph -> ch ) |
||
Assertion | rspcedvd | |- ( ph -> E. x e. B ps ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | rspcedvd.1 | |- ( ph -> A e. B ) |
|
2 | rspcedvd.2 | |- ( ( ph /\ x = A ) -> ( ps <-> ch ) ) |
|
3 | rspcedvd.3 | |- ( ph -> ch ) |
|
4 | 1 2 | rspcedv | |- ( ph -> ( ch -> E. x e. B ps ) ) |
5 | 3 4 | mpd | |- ( ph -> E. x e. B ps ) |