Description: Reverse closure for the class of universal property in opposite categories. (Contributed by Zhi Wang, 4-Nov-2025)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | oppcuprcl2.x | |- ( ph -> X ( <. F , G >. ( O UP P ) W ) M ) |
|
| oppcuprcl2.p | |- P = ( oppCat ` E ) |
||
| oppcuprcl5.j | |- J = ( Hom ` E ) |
||
| Assertion | oppcuprcl5 | |- ( ph -> M e. ( ( F ` X ) J W ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | oppcuprcl2.x | |- ( ph -> X ( <. F , G >. ( O UP P ) W ) M ) |
|
| 2 | oppcuprcl2.p | |- P = ( oppCat ` E ) |
|
| 3 | oppcuprcl5.j | |- J = ( Hom ` E ) |
|
| 4 | eqid | |- ( Hom ` P ) = ( Hom ` P ) |
|
| 5 | 1 4 | uprcl5 | |- ( ph -> M e. ( W ( Hom ` P ) ( F ` X ) ) ) |
| 6 | 3 2 | oppchom | |- ( W ( Hom ` P ) ( F ` X ) ) = ( ( F ` X ) J W ) |
| 7 | 5 6 | eleqtrdi | |- ( ph -> M e. ( ( F ` X ) J W ) ) |