defpred S1[ set , set ] means ex AR being auxiliary Relation of L st
( AR = $2 & ( for x, y being set holds
( [x,y] in AR iff ex x', y' being Element of L ex s' being Function of L,(InclPoset (Ids L)) st
( x' = x & y' = y & s' = $1 & x' in s' . y' ) ) ) );
A1: for a being set st a in the carrier of (MonSet L) holds
ex b being set st
( b in the carrier of (InclPoset (Aux L)) & S1[a,b] )
proof
let a be set ; :: thesis: ( a in the carrier of (MonSet L) implies ex b being set st
( b in the carrier of (InclPoset (Aux L)) & S1[a,b] ) )

assume A2: a in the carrier of (MonSet L) ; :: thesis: ex b being set st
( b in the carrier of (InclPoset (Aux L)) & S1[a,b] )

defpred S2[ set , set ] means ex x', y' being Element of L ex s' being Function of L,(InclPoset (Ids L)) st
( x' = $1 & y' = $2 & s' = a & x' in s' . y' );
consider R being Relation of the carrier of L,the carrier of L such that
A3: for x, y being set holds
( [x,y] in R iff ( x in the carrier of L & y in the carrier of L & S2[x,y] ) ) from RELSET_1:sch 1();
reconsider R = R as Relation of L ;
now
thus R is auxiliary(i) :: thesis: ( R is auxiliary(ii) & R is auxiliary(iii) & R is auxiliary(iv) )
proof
let x, y be Element of L; :: according to WAYBEL_4:def 4 :: thesis: ( [x,y] in R implies x <= y )
assume [x,y] in R ; :: thesis: x <= y
then consider x', y' being Element of L, s' being Function of L,(InclPoset (Ids L)) such that
A4: ( x' = x & y' = y & s' = a & x' in s' . y' ) by A3;
consider s being Function of L,(InclPoset (Ids L)) such that
A5: ( a = s & s is monotone & ( for x being Element of L holds s . x c= downarrow x ) ) by A2, Def14;
s' . y c= downarrow y by A4, A5;
hence x <= y by A4, WAYBEL_0:17; :: thesis: verum
end;
thus R is auxiliary(ii) :: thesis: ( R is auxiliary(iii) & R is auxiliary(iv) )
proof
let x, y, z, u be Element of L; :: according to WAYBEL_4:def 5 :: thesis: ( u <= x & [x,y] in R & y <= z implies [u,z] in R )
assume A6: ( u <= x & [x,y] in R & y <= z ) ; :: thesis: [u,z] in R
then consider x', y' being Element of L, s' being Function of L,(InclPoset (Ids L)) such that
A7: ( x' = x & y' = y & s' = a & x' in s' . y' ) by A3;
consider s being Function of L,(InclPoset (Ids L)) such that
A8: ( a = s & s is monotone & ( for x being Element of L holds s . x c= downarrow x ) ) by A2, Def14;
reconsider sy = s . y, sz = s . z as Element of (InclPoset (Ids L)) ;
sy <= sz by A6, A8, ORDERS_3:def 5;
then A9: s . y c= s . z by YELLOW_1:3;
s . z in the carrier of (InclPoset (Ids L)) ;
then s . z in Ids L by YELLOW_1:1;
then consider sz being Ideal of L such that
A10: s . z = sz ;
u in sz by A6, A7, A8, A9, A10, WAYBEL_0:def 19;
hence [u,z] in R by A3, A8, A10; :: thesis: verum
end;
thus R is auxiliary(iii) :: thesis: R is auxiliary(iv)
proof
let x, y, z be Element of L; :: according to WAYBEL_4:def 6 :: thesis: ( [x,z] in R & [y,z] in R implies [(x "\/" y),z] in R )
assume A11: ( [x,z] in R & [y,z] in R ) ; :: thesis: [(x "\/" y),z] in R
then consider x1, z1 being Element of L, s1 being Function of L,(InclPoset (Ids L)) such that
A12: ( x1 = x & z1 = z & s1 = a & x1 in s1 . z1 ) by A3;
consider y2, z2 being Element of L, s2 being Function of L,(InclPoset (Ids L)) such that
A13: ( y2 = y & z2 = z & s2 = a & y2 in s2 . z2 ) by A3, A11;
s1 . z in the carrier of (InclPoset (Ids L)) ;
then s1 . z in Ids L by YELLOW_1:1;
then consider sz being Ideal of L such that
A14: s1 . z = sz ;
consider z3 being Element of L such that
A15: ( z3 in sz & x <= z3 & y <= z3 ) by A12, A13, A14, WAYBEL_0:def 1;
ex q being Element of L st
( x <= q & y <= q & ( for c being Element of L st x <= c & y <= c holds
q <= c ) ) by LATTICE3:def 10;
then x "\/" y <= z3 by A15, LATTICE3:def 13;
then x "\/" y in sz by A15, WAYBEL_0:def 19;
hence [(x "\/" y),z] in R by A3, A12, A14; :: thesis: verum
end;
thus R is auxiliary(iv) :: thesis: verum
proof
let x be Element of L; :: according to WAYBEL_4:def 7 :: thesis: [(Bottom L),x] in R
reconsider x' = Bottom L, y' = x as Element of L ;
consider s' being Function of L,(InclPoset (Ids L)) such that
A16: ( a = s' & s' is monotone & ( for x being Element of L holds s' . x c= downarrow x ) ) by A2, Def14;
s' . y' in the carrier of (InclPoset (Ids L)) ;
then s' . y' in Ids L by YELLOW_1:1;
then consider sy being Ideal of L such that
A17: sy = s' . y' ;
x' in sy by Th21;
hence [(Bottom L),x] in R by A3, A16, A17; :: thesis: verum
end;
end;
then reconsider R = R as auxiliary Relation of L ;
A18: for x, y being set holds
( [x,y] in R iff ex x', y' being Element of L ex s' being Function of L,(InclPoset (Ids L)) st
( x' = x & y' = y & s' = a & x' in s' . y' ) ) by A3;
take b = R; :: thesis: ( b in the carrier of (InclPoset (Aux L)) & S1[a,b] )
b in Aux L by Def9;
hence ( b in the carrier of (InclPoset (Aux L)) & S1[a,b] ) by A18, YELLOW_1:1; :: thesis: verum
end;
consider f being Function of the carrier of (MonSet L),the carrier of (InclPoset (Aux L)) such that
A19: for a being set st a in the carrier of (MonSet L) holds
S1[a,f . a] from FUNCT_2:sch 1(A1);
reconsider f' = f as Function of (MonSet L),(InclPoset (Aux L)) ;
take f' ; :: thesis: for s being set st s in the carrier of (MonSet L) holds
ex AR being auxiliary Relation of L st
( AR = f' . s & ( for x, y being set holds
( [x,y] in AR iff ex x', y' being Element of L ex s' being Function of L,(InclPoset (Ids L)) st
( x' = x & y' = y & s' = s & x' in s' . y' ) ) ) )

let s be set ; :: thesis: ( s in the carrier of (MonSet L) implies ex AR being auxiliary Relation of L st
( AR = f' . s & ( for x, y being set holds
( [x,y] in AR iff ex x', y' being Element of L ex s' being Function of L,(InclPoset (Ids L)) st
( x' = x & y' = y & s' = s & x' in s' . y' ) ) ) ) )

assume A20: s in the carrier of (MonSet L) ; :: thesis: ex AR being auxiliary Relation of L st
( AR = f' . s & ( for x, y being set holds
( [x,y] in AR iff ex x', y' being Element of L ex s' being Function of L,(InclPoset (Ids L)) st
( x' = x & y' = y & s' = s & x' in s' . y' ) ) ) )

then reconsider s' = s as Element of (MonSet L) ;
f' . s' in the carrier of (InclPoset (Aux L)) ;
then f' . s' in Aux L by YELLOW_1:1;
then reconsider fs = f' . s' as auxiliary Relation of L by Def9;
take fs ; :: thesis: ( fs = f' . s & ( for x, y being set holds
( [x,y] in fs iff ex x', y' being Element of L ex s' being Function of L,(InclPoset (Ids L)) st
( x' = x & y' = y & s' = s & x' in s' . y' ) ) ) )

ex AR being auxiliary Relation of L st
( AR = f' . s & ( for x, y being set holds
( [x,y] in AR iff ex x', y' being Element of L ex s' being Function of L,(InclPoset (Ids L)) st
( x' = x & y' = y & s' = s & x' in s' . y' ) ) ) ) by A19, A20;
hence ( fs = f' . s & ( for x, y being set holds
( [x,y] in fs iff ex x', y' being Element of L ex s' being Function of L,(InclPoset (Ids L)) st
( x' = x & y' = y & s' = s & x' in s' . y' ) ) ) ) ; :: thesis: verum