Description: Double restricted existential uniqueness implies restricted existential uniqueness with restricted existence. (Contributed by AV, 5-Jul-2023)
Ref | Expression | ||
---|---|---|---|
Assertion | 2reureurex | |- ( E! x e. A , y e. B ph -> E! x e. A E. y e. B ph ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-2reu | |- ( E! x e. A , y e. B ph <-> ( E! x e. A E. y e. B ph /\ E! y e. B E. x e. A ph ) ) |
|
2 | 1 | simplbi | |- ( E! x e. A , y e. B ph -> E! x e. A E. y e. B ph ) |