Metamath Proof Explorer
Description: Restricted existential specialization, using implicit substitution.
(Contributed by NM, 26-May-1998) Drop ax-10 , ax-11 , ax-12 .
(Revised by SN, 12-Dec-2023)
|
|
Ref |
Expression |
|
Hypothesis |
rspcv.1 |
|- ( x = A -> ( ph <-> ps ) ) |
|
Assertion |
rspcev |
|- ( ( A e. B /\ ps ) -> E. x e. B ph ) |
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
rspcv.1 |
|- ( x = A -> ( ph <-> ps ) ) |
2 |
|
id |
|- ( A e. B -> A e. B ) |
3 |
1
|
adantl |
|- ( ( A e. B /\ x = A ) -> ( ph <-> ps ) ) |
4 |
2 3
|
rspcedv |
|- ( A e. B -> ( ps -> E. x e. B ph ) ) |
5 |
4
|
imp |
|- ( ( A e. B /\ ps ) -> E. x e. B ph ) |