Description: A virtual deduction elimination rule. (Contributed by Alan Sare, 24-Jun-2011) (Proof modification is discouraged.) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | e100.1 | |- (. ph ->. ps ). |
|
| e100.2 | |- ch |
||
| e100.3 | |- th |
||
| e100.4 | |- ( ps -> ( ch -> ( th -> ta ) ) ) |
||
| Assertion | e100 | |- (. ph ->. ta ). |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | e100.1 | |- (. ph ->. ps ). |
|
| 2 | e100.2 | |- ch |
|
| 3 | e100.3 | |- th |
|
| 4 | e100.4 | |- ( ps -> ( ch -> ( th -> ta ) ) ) |
|
| 5 | 2 | vd01 | |- (. ph ->. ch ). |
| 6 | 3 | vd01 | |- (. ph ->. th ). |
| 7 | 1 5 6 4 | e111 | |- (. ph ->. ta ). |