Description: Version of isseti with a class variable V in the hypothesis instead of _V for extra generality. This is indeed more general than isseti as long as elex is not available (and the non-dependence of bj-isseti on special properties of the universal class _V is obvious). Use bj-issetiv instead when sufficient (in particular when V is substituted for _V ). (Contributed by BJ, 13-Jun-2019) (Proof modification is discouraged.)
Ref | Expression | ||
---|---|---|---|
Hypothesis | bj-isseti.1 | |- A e. V |
|
Assertion | bj-isseti | |- E. x x = A |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | bj-isseti.1 | |- A e. V |
|
2 | elisset | |- ( A e. V -> E. x x = A ) |
|
3 | 1 2 | ax-mp | |- E. x x = A |