Description: The characteristic property of monuples. Note that this holds without sethood hypotheses. (Contributed by BJ, 6-Apr-2019)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | bj-1uplth | |- ( (| A |) = (| B |) <-> A = B ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | bj-pr1eq | |- ( (| A |) = (| B |) -> pr1 (| A |) = pr1 (| B |) ) |
|
| 2 | bj-pr11val | |- pr1 (| A |) = A |
|
| 3 | bj-pr11val | |- pr1 (| B |) = B |
|
| 4 | 1 2 3 | 3eqtr3g | |- ( (| A |) = (| B |) -> A = B ) |
| 5 | bj-1upleq | |- ( A = B -> (| A |) = (| B |) ) |
|
| 6 | 4 5 | impbii | |- ( (| A |) = (| B |) <-> A = B ) |