Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Hypothesis | bnj1095.1 | |- ( ph <-> A. x e. A ps ) |
|
Assertion | bnj1095 | |- ( ph -> A. x ph ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | bnj1095.1 | |- ( ph <-> A. x e. A ps ) |
|
2 | hbra1 | |- ( A. x e. A ps -> A. x A. x e. A ps ) |
|
3 | 1 2 | hbxfrbi | |- ( ph -> A. x ph ) |