let C1, C2 be Categorial full Category; :: thesis: ( the carrier of C1 = the carrier of C2 implies CatStr(# the carrier of C1,the carrier' of C1,the Source of C1,the Target of C1,the Comp of C1,the Id of C1 #) = CatStr(# the carrier of C2,the carrier' of C2,the Source of C2,the Target of C2,the Comp of C2,the Id of C2 #) )
assume A1: the carrier of C1 = the carrier of C2 ; :: thesis: CatStr(# the carrier of C1,the carrier' of C1,the Source of C1,the Target of C1,the Comp of C1,the Id of C1 #) = CatStr(# the carrier of C2,the carrier' of C2,the Source of C2,the Target of C2,the Comp of C2,the Id of C2 #)
reconsider A = the carrier of C1 as non empty categorial set by Def6;
set B = { (m `2 ) where m is Morphism of C1 : verum } ;
consider m being Morphism of C1;
m `2 in { (m `2 ) where m is Morphism of C1 : verum } ;
then reconsider B = { (m `2 ) where m is Morphism of C1 : verum } as non empty set ;
reconsider D1 = CatStr(# the carrier of C1,the carrier' of C1,the Source of C1,the Target of C1,the Comp of C1,the Id of C1 #), D2 = CatStr(# the carrier of C2,the carrier' of C2,the Source of C2,the Target of C2,the Comp of C2,the Id of C2 #) as strict Category by Th1;
A2: ( D1 is Categorial & D2 is Categorial ) by Th10;
A3: now
let a, b be Element of A; :: thesis: for F being Functor of a,b holds
( [[a,b],F] is Morphism of CatStr(# the carrier of C1,the carrier' of C1,the Source of C1,the Target of C1,the Comp of C1,the Id of C1 #) iff F in B )

let F be Functor of a,b; :: thesis: ( [[a,b],F] is Morphism of CatStr(# the carrier of C1,the carrier' of C1,the Source of C1,the Target of C1,the Comp of C1,the Id of C1 #) iff F in B )
reconsider m = [[a,b],F] as Morphism of C1 by Def8;
m `2 = F by MCART_1:7;
hence ( [[a,b],F] is Morphism of CatStr(# the carrier of C1,the carrier' of C1,the Source of C1,the Target of C1,the Comp of C1,the Id of C1 #) iff F in B ) ; :: thesis: verum
end;
now
let a, b be Element of A; :: thesis: for F being Functor of a,b holds
( [[a,b],F] is Morphism of CatStr(# the carrier of C2,the carrier' of C2,the Source of C2,the Target of C2,the Comp of C2,the Id of C2 #) iff F in B )

let F be Functor of a,b; :: thesis: ( [[a,b],F] is Morphism of CatStr(# the carrier of C2,the carrier' of C2,the Source of C2,the Target of C2,the Comp of C2,the Id of C2 #) iff F in B )
reconsider a' = a, b' = b as Object of C2 by A1;
( cat a' = a & cat b' = b ) by Th16;
then reconsider m2 = [[a,b],F] as Morphism of C2 by Def8;
reconsider m = [[a,b],F] as Morphism of C1 by Def8;
( m `2 = F & m2 = m2 ) by MCART_1:7;
hence ( [[a,b],F] is Morphism of CatStr(# the carrier of C2,the carrier' of C2,the Source of C2,the Target of C2,the Comp of C2,the Id of C2 #) iff F in B ) ; :: thesis: verum
end;
hence CatStr(# the carrier of C1,the carrier' of C1,the Source of C1,the Target of C1,the Comp of C1,the Id of C1 #) = CatStr(# the carrier of C2,the carrier' of C2,the Source of C2,the Target of C2,the Comp of C2,the Id of C2 #) by A1, A2, A3, Th18; :: thesis: verum