Description: Deduction conjoining antecedent to left of consequent in nested implication. (Contributed by NM, 10-Aug-1994) (Proof shortened by Wolf Lammen, 7-Dec-2012)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | anc2li.1 | |- ( ph -> ( ps -> ch ) )  | 
					|
| Assertion | anc2li | |- ( ph -> ( ps -> ( ph /\ ch ) ) )  | 
				
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | anc2li.1 | |- ( ph -> ( ps -> ch ) )  | 
						|
| 2 | id | |- ( ph -> ph )  | 
						|
| 3 | 1 2 | jctild | |- ( ph -> ( ps -> ( ph /\ ch ) ) )  |