Description: Obsolete version of euim as of 1-Oct-2023. (Contributed by NM, 19-Oct-2005) (Proof shortened by Andrew Salmon, 14-Jun-2011) (New usage is discouraged.) (Proof modification is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | euimOLD | |- ( ( E. x ph /\ A. x ( ph -> ps ) ) -> ( E! x ps -> E! x ph ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ax-1 | |- ( E. x ph -> ( E! x ps -> E. x ph ) ) |
|
2 | euimmo | |- ( A. x ( ph -> ps ) -> ( E! x ps -> E* x ph ) ) |
|
3 | 1 2 | anim12ii | |- ( ( E. x ph /\ A. x ( ph -> ps ) ) -> ( E! x ps -> ( E. x ph /\ E* x ph ) ) ) |
4 | df-eu | |- ( E! x ph <-> ( E. x ph /\ E* x ph ) ) |
|
5 | 3 4 | syl6ibr | |- ( ( E. x ph /\ A. x ( ph -> ps ) ) -> ( E! x ps -> E! x ph ) ) |