Description: Technical lemma for bnj97 . This lemma may no longer be used or have become an indirect lemma of the theorem in question (i.e. a lemma of a lemma... of the theorem). (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | bnj93 | |- ( ( R _FrSe A /\ x e. A ) -> _pred ( x , A , R ) e. _V ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-bnj15 | |- ( R _FrSe A <-> ( R Fr A /\ R _Se A ) ) |
|
2 | 1 | simprbi | |- ( R _FrSe A -> R _Se A ) |
3 | df-bnj13 | |- ( R _Se A <-> A. x e. A _pred ( x , A , R ) e. _V ) |
|
4 | 2 3 | sylib | |- ( R _FrSe A -> A. x e. A _pred ( x , A , R ) e. _V ) |
5 | 4 | r19.21bi | |- ( ( R _FrSe A /\ x e. A ) -> _pred ( x , A , R ) e. _V ) |