Description: A substitution into a theorem. (Contributed by NM, 1-Mar-2008) (Proof shortened by Mario Carneiro, 13-Oct-2016)
Ref | Expression | ||
---|---|---|---|
Hypothesis | sbcth2.1 | |- ( x e. B -> ph ) |
|
Assertion | sbcth2 | |- ( A e. B -> [. A / x ]. ph ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | sbcth2.1 | |- ( x e. B -> ph ) |
|
2 | 1 | rgen | |- A. x e. B ph |
3 | rspsbc | |- ( A e. B -> ( A. x e. B ph -> [. A / x ]. ph ) ) |
|
4 | 2 3 | mpi | |- ( A e. B -> [. A / x ]. ph ) |