Description: A set equals the union of its singleton. Theorem 8.2 of Quine p. 53. (Contributed by NM, 30-Aug-1993)
Ref | Expression | ||
---|---|---|---|
Hypothesis | unisn.1 | |
|
Assertion | unisn | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | unisn.1 | |
|
2 | unisng | |
|
3 | 1 2 | ax-mp | |