Description: Rule that applies hbnae to antecedent. Usage of this theorem is discouraged because it depends on ax-13 . (Contributed by NM, 15-May-1993) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | hbnaes.1 | |- ( A. z -. A. x x = y -> ph ) | |
| Assertion | hbnaes | |- ( -. A. x x = y -> ph ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | hbnaes.1 | |- ( A. z -. A. x x = y -> ph ) | |
| 2 | hbnae | |- ( -. A. x x = y -> A. z -. A. x x = y ) | |
| 3 | 2 1 | syl | |- ( -. A. x x = y -> ph ) |