Description: A virtual deduction elimination rule. (Contributed by Alan Sare, 13-Jun-2015) (Proof modification is discouraged.) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | el0321old.1 | |- ph |
|
| el0321old.2 | |- (. (. ps ,. ch ,. th ). ->. ta ). |
||
| el0321old.3 | |- ( ( ph /\ ta ) -> et ) |
||
| Assertion | el0321old | |- (. (. ps ,. ch ,. th ). ->. et ). |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | el0321old.1 | |- ph |
|
| 2 | el0321old.2 | |- (. (. ps ,. ch ,. th ). ->. ta ). |
|
| 3 | el0321old.3 | |- ( ( ph /\ ta ) -> et ) |
|
| 4 | 2 | dfvd3ani | |- ( ( ps /\ ch /\ th ) -> ta ) |
| 5 | 1 4 3 | eel0321old | |- ( ( ps /\ ch /\ th ) -> et ) |
| 6 | 5 | dfvd3anir | |- (. (. ps ,. ch ,. th ). ->. et ). |