Description: The successor of a set is a set (generalization). (Contributed by NM, 5-Jun-1994)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | sucexg | |- ( A e. V -> suc A e. _V ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | elex | |- ( A e. V -> A e. _V ) |
|
| 2 | sucexb | |- ( A e. _V <-> suc A e. _V ) |
|
| 3 | 1 2 | sylib | |- ( A e. V -> suc A e. _V ) |