Description: Deduction of abstraction subclass from implication. (Contributed by SN, 22-Dec-2024)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | ssabdv.1 | |- ( ph -> ( x e. A -> ps ) ) | |
| Assertion | ssabdv | |- ( ph -> A C_ { x | ps } ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | ssabdv.1 | |- ( ph -> ( x e. A -> ps ) ) | |
| 2 | abid1 |  |-  A = { x | x e. A } | |
| 3 | 1 | ss2abdv |  |-  ( ph -> { x | x e. A } C_ { x | ps } ) | 
| 4 | 2 3 | eqsstrid |  |-  ( ph -> A C_ { x | ps } ) |