Description: Inference similar to Theorem 19.23 of Margaris p. 90. (Contributed by Alan Sare, 21-Apr-2013) (Proof modification is discouraged.) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | exlimexi.1 | |- ( ps -> A. x ps ) | |
| exlimexi.2 | |- ( E. x ph -> ( ph -> ps ) ) | ||
| Assertion | exlimexi | |- ( E. x ph -> ps ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | exlimexi.1 | |- ( ps -> A. x ps ) | |
| 2 | exlimexi.2 | |- ( E. x ph -> ( ph -> ps ) ) | |
| 3 | hbe1 | |- ( E. x ph -> A. x E. x ph ) | |
| 4 | 3 1 2 | exlimdh | |- ( E. x ph -> ( E. x ph -> ps ) ) | 
| 5 | 4 | pm2.43i | |- ( E. x ph -> ps ) |