Description: Exportation inference with commuted antecedents. (Contributed by NM, 25-May-2005)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | ex.1 | |- ( ( ph /\ ps ) -> ch )  | 
					|
| Assertion | expcom | |- ( ps -> ( ph -> ch ) )  | 
				
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | ex.1 | |- ( ( ph /\ ps ) -> ch )  | 
						|
| 2 | 1 | ex | |- ( ph -> ( ps -> ch ) )  | 
						
| 3 | 2 | com12 | |- ( ps -> ( ph -> ch ) )  |