Description: Deduction of abstraction subclass from implication. (Contributed by NM, 20-Jan-2006)
Ref | Expression | ||
---|---|---|---|
Hypothesis | abssdv.1 | |- ( ph -> ( ps -> x e. A ) ) |
|
Assertion | abssdv | |- ( ph -> { x | ps } C_ A ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | abssdv.1 | |- ( ph -> ( ps -> x e. A ) ) |
|
2 | 1 | alrimiv | |- ( ph -> A. x ( ps -> x e. A ) ) |
3 | abss | |- ( { x | ps } C_ A <-> A. x ( ps -> x e. A ) ) |
|
4 | 2 3 | sylibr | |- ( ph -> { x | ps } C_ A ) |