Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | bnj1266.1 | |- ( ch -> E. x ( ph /\ ps ) )  | 
					|
| Assertion | bnj1266 | |- ( ch -> E. x ps )  | 
				
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | bnj1266.1 | |- ( ch -> E. x ( ph /\ ps ) )  | 
						|
| 2 | simpr | |- ( ( ph /\ ps ) -> ps )  | 
						|
| 3 | 1 2 | bnj593 | |- ( ch -> E. x ps )  |