| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							upeu3.i | 
							 |-  ( ph -> I = ( Iso ` D ) )  | 
						
						
							| 2 | 
							
								
							 | 
							upeu3.o | 
							 |-  ( ph -> .o. = ( <. W , ( F ` X ) >. ( comp ` E ) ( F ` Y ) ) )  | 
						
						
							| 3 | 
							
								
							 | 
							upeu3.x | 
							 |-  ( ph -> X ( <. F , G >. ( D UP E ) W ) M )  | 
						
						
							| 4 | 
							
								
							 | 
							upeu3.y | 
							 |-  ( ph -> Y ( <. F , G >. ( D UP E ) W ) N )  | 
						
						
							| 5 | 
							
								
							 | 
							eqid | 
							 |-  ( Base ` D ) = ( Base ` D )  | 
						
						
							| 6 | 
							
								
							 | 
							eqid | 
							 |-  ( Base ` E ) = ( Base ` E )  | 
						
						
							| 7 | 
							
								
							 | 
							eqid | 
							 |-  ( Hom ` D ) = ( Hom ` D )  | 
						
						
							| 8 | 
							
								
							 | 
							eqid | 
							 |-  ( Hom ` E ) = ( Hom ` E )  | 
						
						
							| 9 | 
							
								
							 | 
							eqid | 
							 |-  ( comp ` E ) = ( comp ` E )  | 
						
						
							| 10 | 
							
								3
							 | 
							uprcl2 | 
							 |-  ( ph -> F ( D Func E ) G )  | 
						
						
							| 11 | 
							
								3 5
							 | 
							uprcl4 | 
							 |-  ( ph -> X e. ( Base ` D ) )  | 
						
						
							| 12 | 
							
								4 5
							 | 
							uprcl4 | 
							 |-  ( ph -> Y e. ( Base ` D ) )  | 
						
						
							| 13 | 
							
								3 6
							 | 
							uprcl3 | 
							 |-  ( ph -> W e. ( Base ` E ) )  | 
						
						
							| 14 | 
							
								3 8
							 | 
							uprcl5 | 
							 |-  ( ph -> M e. ( W ( Hom ` E ) ( F ` X ) ) )  | 
						
						
							| 15 | 
							
								5 7 8 9 3
							 | 
							isup2 | 
							 |-  ( ph -> A. y e. ( Base ` D ) A. g e. ( W ( Hom ` E ) ( F ` y ) ) E! k e. ( X ( Hom ` D ) y ) g = ( ( ( X G y ) ` k ) ( <. W , ( F ` X ) >. ( comp ` E ) ( F ` y ) ) M ) )  | 
						
						
							| 16 | 
							
								4 8
							 | 
							uprcl5 | 
							 |-  ( ph -> N e. ( W ( Hom ` E ) ( F ` Y ) ) )  | 
						
						
							| 17 | 
							
								5 7 8 9 4
							 | 
							isup2 | 
							 |-  ( ph -> A. y e. ( Base ` D ) A. g e. ( W ( Hom ` E ) ( F ` y ) ) E! k e. ( Y ( Hom ` D ) y ) g = ( ( ( Y G y ) ` k ) ( <. W , ( F ` Y ) >. ( comp ` E ) ( F ` y ) ) N ) )  | 
						
						
							| 18 | 
							
								5 6 7 8 9 10 11 12 13 14 15 16 17
							 | 
							upeu | 
							 |-  ( ph -> E! r e. ( X ( Iso ` D ) Y ) N = ( ( ( X G Y ) ` r ) ( <. W , ( F ` X ) >. ( comp ` E ) ( F ` Y ) ) M ) )  | 
						
						
							| 19 | 
							
								1
							 | 
							oveqd | 
							 |-  ( ph -> ( X I Y ) = ( X ( Iso ` D ) Y ) )  | 
						
						
							| 20 | 
							
								2
							 | 
							oveqd | 
							 |-  ( ph -> ( ( ( X G Y ) ` r ) .o. M ) = ( ( ( X G Y ) ` r ) ( <. W , ( F ` X ) >. ( comp ` E ) ( F ` Y ) ) M ) )  | 
						
						
							| 21 | 
							
								20
							 | 
							eqeq2d | 
							 |-  ( ph -> ( N = ( ( ( X G Y ) ` r ) .o. M ) <-> N = ( ( ( X G Y ) ` r ) ( <. W , ( F ` X ) >. ( comp ` E ) ( F ` Y ) ) M ) ) )  | 
						
						
							| 22 | 
							
								19 21
							 | 
							reueqbidv | 
							 |-  ( ph -> ( E! r e. ( X I Y ) N = ( ( ( X G Y ) ` r ) .o. M ) <-> E! r e. ( X ( Iso ` D ) Y ) N = ( ( ( X G Y ) ` r ) ( <. W , ( F ` X ) >. ( comp ` E ) ( F ` Y ) ) M ) ) )  | 
						
						
							| 23 | 
							
								18 22
							 | 
							mpbird | 
							 |-  ( ph -> E! r e. ( X I Y ) N = ( ( ( X G Y ) ` r ) .o. M ) )  |