Description: First of two weakened versions of ax7v , with an extra disjoint variable condition on x , z , see comments there. (Contributed by BJ, 7-Dec-2020)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | ax7v1 | |- ( x = y -> ( x = z -> y = z ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ax7v | |- ( x = y -> ( x = z -> y = z ) ) |