Description: Reverse closure for the class of universal property. (Contributed by Zhi Wang, 25-Sep-2025)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | uprcl.c | |- C = ( Base ` E )  | 
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| Assertion | uprcl | |- ( X e. ( F ( D UP E ) W ) -> ( F e. ( D Func E ) /\ W e. C ) )  | 
				
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | uprcl.c | |- C = ( Base ` E )  | 
						|
| 2 | eqid | |- ( Base ` D ) = ( Base ` D )  | 
						|
| 3 | eqid | |- ( Hom ` D ) = ( Hom ` D )  | 
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| 4 | eqid | |- ( Hom ` E ) = ( Hom ` E )  | 
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| 5 | eqid | |- ( comp ` E ) = ( comp ` E )  | 
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| 6 | 2 1 3 4 5 | upfval |  |-  ( D UP E ) = ( f e. ( D Func E ) , w e. C |-> { <. x , m >. | ( ( x e. ( Base ` D ) /\ m e. ( w ( Hom ` E ) ( ( 1st ` f ) ` x ) ) ) /\ A. y e. ( Base ` D ) A. g e. ( w ( Hom ` E ) ( ( 1st ` f ) ` y ) ) E! k e. ( x ( Hom ` D ) y ) g = ( ( ( x ( 2nd ` f ) y ) ` k ) ( <. w , ( ( 1st ` f ) ` x ) >. ( comp ` E ) ( ( 1st ` f ) ` y ) ) m ) ) } ) | 
						
| 7 | 6 | elmpocl | |- ( X e. ( F ( D UP E ) W ) -> ( F e. ( D Func E ) /\ W e. C ) )  |