let AA be non empty categorial set ; :: thesis: ex C being strict Categorial full Category st the carrier of C = AA
set dFF = { (Funct a,b) where a, b is Element of AA : verum } ;
consider a, b being Element of AA, f being Functor of a,b;
( f in Funct a,b & Funct a,b in { (Funct a,b) where a, b is Element of AA : verum } )
by CAT_2:def 2;
then reconsider FF = union { (Funct a,b) where a, b is Element of AA : verum } as non empty set by TARSKI:def 4;
A1:
now let A,
B,
C be
Element of
AA;
:: thesis: for F being Functor of A,B
for G being Functor of B,C st F in FF & G in FF holds
G * F in FFlet F be
Functor of
A,
B;
:: thesis: for G being Functor of B,C st F in FF & G in FF holds
G * F in FFlet G be
Functor of
B,
C;
:: thesis: ( F in FF & G in FF implies G * F in FF )assume
(
F in FF &
G in FF )
;
:: thesis: G * F in FF
(
G * F in Funct A,
C &
Funct A,
C in { (Funct a,b) where a, b is Element of AA : verum } )
by CAT_2:def 2;
hence
G * F in FF
by TARSKI:def 4;
:: thesis: verum end;
then consider C being strict Categorial Category such that
A2:
( the carrier of C = AA & ( for A, B being Element of AA
for F being Functor of A,B holds
( [[A,B],F] is Morphism of C iff F in FF ) ) )
by A1, Th17;
C is full
proof
let a,
b be
Category;
:: according to CAT_5:def 8 :: thesis: ( a is Object of C & b is Object of C implies for F being Functor of a,b holds [[a,b],F] is Morphism of C )
assume
(
a is
Object of
C &
b is
Object of
C )
;
:: thesis: for F being Functor of a,b holds [[a,b],F] is Morphism of C
then reconsider A =
a,
B =
b as
Element of
AA by A2;
let F be
Functor of
a,
b;
:: thesis: [[a,b],F] is Morphism of C
(
F in Funct A,
B &
Funct A,
B in { (Funct a,b) where a, b is Element of AA : verum } )
by CAT_2:def 2;
then
F in FF
by TARSKI:def 4;
then
[[A,B],F] is
Morphism of
C
by A2;
hence
[[a,b],F] is
Morphism of
C
;
:: thesis: verum
end;
hence
ex C being strict Categorial full Category st the carrier of C = AA
by A2; :: thesis: verum