Description: Deduction rule: Given "all some one" applied to a class, you can extract the "for all" part. (Contributed by David A. Wheeler, 21-Jul-2026)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | ralseu1d.1 | |- ( ph -> AE! x e. A ( ps -> ch ) ) |
|
| Assertion | ralseu1d | |- ( ph -> A. x e. A ( ps -> ch ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ralseu1d.1 | |- ( ph -> AE! x e. A ( ps -> ch ) ) |
|
| 2 | df-ralseu | |- ( AE! x e. A ( ps -> ch ) <-> ( A. x e. A ( ps -> ch ) /\ E! x e. A ps ) ) |
|
| 3 | 1 2 | sylib | |- ( ph -> ( A. x e. A ( ps -> ch ) /\ E! x e. A ps ) ) |
| 4 | 3 | simpld | |- ( ph -> A. x e. A ( ps -> ch ) ) |