Description: A virtual deduction elimination rule. (Contributed by Alan Sare, 12-Jun-2011) (Proof modification is discouraged.) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | e32.1 | |- (. ph ,. ps ,. ch ->. th ). | |
| e32.2 | |- (. ph ,. ps ->. ta ). | ||
| e32.3 | |- ( th -> ( ta -> et ) ) | ||
| Assertion | e32 | |- (. ph ,. ps ,. ch ->. et ). | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | e32.1 | |- (. ph ,. ps ,. ch ->. th ). | |
| 2 | e32.2 | |- (. ph ,. ps ->. ta ). | |
| 3 | e32.3 | |- ( th -> ( ta -> et ) ) | |
| 4 | 2 | vd23 | |- (. ph ,. ps ,. ch ->. ta ). | 
| 5 | 1 4 3 | e33 | |- (. ph ,. ps ,. ch ->. et ). |