Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | bnj1345.1 | |- ( ph -> E. x ( ps /\ ch ) )  | 
					|
| bnj1345.2 | |- ( th <-> ( ph /\ ps /\ ch ) )  | 
					||
| bnj1345.3 | |- ( ph -> A. x ph )  | 
					||
| Assertion | bnj1345 | |- ( ph -> E. x th )  | 
				
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | bnj1345.1 | |- ( ph -> E. x ( ps /\ ch ) )  | 
						|
| 2 | bnj1345.2 | |- ( th <-> ( ph /\ ps /\ ch ) )  | 
						|
| 3 | bnj1345.3 | |- ( ph -> A. x ph )  | 
						|
| 4 | 1 3 | bnj1275 | |- ( ph -> E. x ( ph /\ ps /\ ch ) )  | 
						
| 5 | 4 2 | bnj1198 | |- ( ph -> E. x th )  |