Description: A set is an element of any sigma-algebra on it. (Contributed by Glauco Siliprandi, 26-Jun-2021)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | salunid.1 | |- ( ph -> S e. SAlg ) |
|
| Assertion | salunid | |- ( ph -> U. S e. S ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | salunid.1 | |- ( ph -> S e. SAlg ) |
|
| 2 | saluni | |- ( S e. SAlg -> U. S e. S ) |
|
| 3 | 1 2 | syl | |- ( ph -> U. S e. S ) |