Description: A theorem is virtually inferred by the 3 virtual hypotheses. (Contributed by Alan Sare, 12-Jun-2011) (Proof modification is discouraged.) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | vd03.1 | |- ph | |
| Assertion | vd03 | |- (. ps ,. ch ,. th ->. ph ). | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | vd03.1 | |- ph | |
| 2 | 1 | a1i | |- ( th -> ph ) | 
| 3 | 2 | a1i | |- ( ch -> ( th -> ph ) ) | 
| 4 | 3 | a1i | |- ( ps -> ( ch -> ( th -> ph ) ) ) | 
| 5 | 4 | dfvd3ir | |- (. ps ,. ch ,. th ->. ph ). |