Description: A set is a member of its power class. Theorem 87 of Suppes p. 47. (Contributed by NM, 5-Aug-1993)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | pwid.1 | |- A e. _V |
|
| Assertion | pwid | |- A e. ~P A |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | pwid.1 | |- A e. _V |
|
| 2 | pwidg | |- ( A e. _V -> A e. ~P A ) |
|
| 3 | 1 2 | ax-mp | |- A e. ~P A |