The Mizar article:

Representation Theorem for Free Continuous Lattices

by
Piotr Rudnicki

Received July 21, 1998

Copyright (c) 1998 Association of Mizar Users

MML identifier: WAYBEL22
[ MML identifier index ]


environ

 vocabulary BHSP_3, WAYBEL_0, LATTICES, TARSKI, ORDINAL2, QUANTAL1, YELLOW_1,
      OPPCAT_1, ORDERS_1, PRE_TOPC, WAYBEL16, FUNCT_1, YELLOW_0, RELAT_1,
      LATTICE3, WAYBEL_5, WELLORD2, FILTER_0, WELLORD1, BOOLE, CAT_1, SUBSET_1,
      SETFAM_1, CARD_1, FILTER_1, SEQM_3, AMI_1, ZF_REFLE, PBOOLE, FUNCOP_1,
      PRALG_1, YELLOW_2, FUNCT_6, CARD_3, FRAENKEL, WAYBEL22;
 notation TARSKI, XBOOLE_0, ZFMISC_1, SUBSET_1, SETFAM_1, RELAT_1, FUNCT_1,
      STRUCT_0, FUNCT_2, FUNCT_6, PRALG_3, GRCAT_1, WELLORD1, CARD_1, CARD_3,
      PRE_TOPC, ORDERS_1, LATTICE3, PBOOLE, MSUALG_1, AMI_1, FRAENKEL,
      YELLOW_0, YELLOW_1, YELLOW_2, YELLOW_7, WAYBEL_0, WAYBEL_1, WAYBEL_3,
      WAYBEL_5, WAYBEL16;
 constructors ORDERS_3, TOPS_2, GRCAT_1, TOLER_1, PRALG_3, WAYBEL_1, WAYBEL_5,
      WAYBEL_8, WAYBEL16;
 clusters STRUCT_0, FUNCT_1, LATTICE3, PBOOLE, PRALG_1, PRVECT_1, AMI_1,
      YELLOW_0, YELLOW_7, WAYBEL_0, WAYBEL_3, WAYBEL_5, WAYBEL_8, WAYBEL16,
      RELSET_1, SUBSET_1, FRAENKEL, XBOOLE_0;
 requirements SUBSET, BOOLE;
 definitions TARSKI, FUNCT_1, ORDERS_3, LATTICE3, WELLORD2, YELLOW_0, WAYBEL_0;
 theorems TARSKI, CARD_1, ZFMISC_1, SETFAM_1, RELAT_1, FUNCT_1, FUNCT_2,
      FUNCT_3, FUNCT_4, FUNCT_6, FUNCOP_1, WELLORD1, WELLORD2, CARD_3,
      PRE_TOPC, GRCAT_1, BORSUK_1, LATTICE3, AMI_1, MSUALG_1, PBOOLE, EXTENS_1,
      YELLOW_0, YELLOW_1, YELLOW_2, WAYBEL_0, WAYBEL_1, WAYBEL_5, WAYBEL11,
      WAYBEL13, WAYBEL14, WAYBEL15, WAYBEL16, WAYBEL17, RELSET_1, WAYBEL_4,
      WAYBEL20, XBOOLE_0, XBOOLE_1;
 schemes FUNCT_1, FUNCT_2, MSSUBFAM, YELLOW_3;

begin :: Preliminaries

Lm1:
for L being complete LATTICE, X being set
 st X c= bool the carrier of L
  holds "/\"(union X, L) = "/\"({inf Y where Y is Subset of L: Y in X}, L)
proof let L be complete LATTICE, X be set such that
A1: X c= bool the carrier of L;
   defpred P[Subset of L] means $1 in X;
   set XX = {Z where Z is Subset of L : P[Z]};
   A2: now let x be set;
    hereby assume x in XX; then consider Z being Subset of L such that
    A3: x = Z & Z in X;
     thus x in X by A3;
    end;
    assume A4: x in X;
     then reconsider x' = x as Subset of L by A1;
       x' in XX by A4;
    hence x in XX;
   end;
    "/\"({"/\"(Y, L) where Y is Subset of L: P[Y]}, L) = "/\"(union XX, L)
   from Inf_of_Infs;
 hence "/\"(union X, L) = "/\"({inf Y where Y is Subset of L: Y in X}, L)
   by A2,TARSKI:2;
end;

Lm2:
for L being complete LATTICE, X being set
 st X c= bool the carrier of L
  holds "\/"(union X, L) = "\/"({sup Y where Y is Subset of L: Y in X}, L)
proof let L be complete LATTICE, X be set such that
A1: X c= bool the carrier of L;
   defpred P[set] means $1 in X;
   set XX = {Z where Z is Subset of L : P[Z]};
   A2: now let x be set;
    hereby assume x in XX; then consider Z being Subset of L such that
    A3: x = Z & Z in X;
     thus x in X by A3;
    end;
    assume A4: x in X;
     then reconsider x' = x as Subset of L by A1;
       x' in XX by A4;
    hence x in XX;
   end;
    "\/"({"\/"(Y, L) where Y is Subset of L: P[Y]}, L) = "\/"(union XX, L)
   from Sup_of_Sups;
 hence "\/"(union X, L) = "\/"
({sup Y where Y is Subset of L: Y in X}, L) by A2,TARSKI:2;
end;

theorem Th1: :: cf. WAYBEL13:9
for L being upper-bounded Semilattice,
    F being non empty directed Subset of InclPoset Filt L
 holds sup F = union F
proof let L be upper-bounded Semilattice,
          F be non empty directed Subset of InclPoset Filt L;
   Filt L = Ids (L opp) by WAYBEL16:7;
 hence sup F = union F by WAYBEL13:9;
end;

theorem Th2:
 for L, S, T being complete (non empty Poset),
     f being CLHomomorphism of L, S, g being CLHomomorphism of S, T
  holds g*f is CLHomomorphism of L, T
proof let L, S, T be complete (non empty Poset),
          f be CLHomomorphism of L, S, g be CLHomomorphism of S, T;
A1: f is infs-preserving & g is infs-preserving &
    f is directed-sups-preserving & g is directed-sups-preserving
       by WAYBEL16:def 1;
then A2: g*f is infs-preserving by WAYBEL20:26;
     g*f is directed-sups-preserving by A1,WAYBEL20:29;
 hence g*f is CLHomomorphism of L, T by A2,WAYBEL16:def 1;
end;

theorem Th3:
 for L being non empty RelStr holds id L is infs-preserving
proof let L be non empty RelStr;
 let X be Subset of L;
 assume
A1: ex_inf_of X, L; set f = id L;
   A2: f = id the carrier of L by GRCAT_1:def 11;
then A3: f.:X = X by BORSUK_1:3;
 thus ex_inf_of f.:X, L by A1,A2,BORSUK_1:3;
 thus inf (f.:X) = f.inf X by A3,GRCAT_1:11;
end;

theorem Th4:
 for L being non empty RelStr holds id L is directed-sups-preserving
proof let L be non empty RelStr;
 let X be Subset of L such that X is non empty directed; assume
A1: ex_sup_of X, L; set f = id L;
   A2: f = id the carrier of L by GRCAT_1:def 11;
then A3: f.:X = X by BORSUK_1:3;
  thus ex_sup_of f.:X, L by A1,A2,BORSUK_1:3;
  thus sup (f.:X) = f.sup X by A3,GRCAT_1:11;
end;

theorem Th5:
 for L being complete (non empty Poset) holds id L is CLHomomorphism of L, L
proof let L be complete (non empty Poset);
A1: id L is directed-sups-preserving by Th4;
     id L is infs-preserving by Th3;
 hence id L is CLHomomorphism of L, L by A1,WAYBEL16:def 1;
end;

theorem Th6:
 for L being upper-bounded with_infima non empty Poset
  holds InclPoset Filt L is CLSubFrame of BoolePoset the carrier of L
proof let L be upper-bounded with_infima non empty Poset;
 set cL = the carrier of L; set BP = BoolePoset cL;
 set cBP = the carrier of BP; set rBP = the InternalRel of BP;
 set IP = InclPoset Filt L; set cIP = the carrier of IP;
 set rIP = the InternalRel of IP;
  A1: BoolePoset cL = InclPoset bool cL by YELLOW_1:4;
      A2: InclPoset bool cL = RelStr(#bool cL, RelIncl bool cL#)
           by YELLOW_1:def 1;
then A3: cBP = bool cL & rBP = RelIncl bool cL by YELLOW_1:4;
    A4: InclPoset Filt L = RelStr(#Filt L, RelIncl Filt L#)
           by YELLOW_1:def 1;
then A5: field rIP = Filt L by WELLORD2:def 1;
A6: Filt L = {X where X is Filter of L: not contradiction}by WAYBEL_0:def 24;
A7: Filt L c= bool cL proof let x be set; assume x in Filt L;
      then consider X being Filter of L such that
    A8: x = X by A6;
      thus x in bool cL by A8;
    end;
 A9: cIP c= cBP proof let x be set; assume x in cIP;
       then consider X being Filter of L such that
    A10: x = X by A4,A6;
     thus x in cBP by A1,A2,A10;
    end;
    rIP c= rBP proof let p be set; assume
   A11: p in rIP;
       then consider x, y being set such that
   A12: p = [x, y] by RELAT_1:def 1;
   A13: x in field rIP & y in field rIP by A11,A12,RELAT_1:30;
       then consider X being Filter of L such that
   A14: x = X by A5,A6;
       consider Y being Filter of L such that
   A15: y = Y by A5,A6,A13;
         X c= Y by A4,A5,A11,A12,A13,A14,A15,WELLORD2:def 1;
   hence p in rBP by A1,A2,A12,A14,A15,WELLORD2:def 1;
  end;
 then reconsider IP as SubRelStr of BP by A9,YELLOW_0:def 13;
     now let p be set;
   A16: rBP|_2 cIP = rBP /\ [:cIP, cIP:] by WELLORD1:def 6;
    hereby assume
   A17: p in rIP;
       then consider x, y being set such that
   A18: p = [x, y] by RELAT_1:def 1;
   A19: x in field rIP & y in field rIP by A17,A18,RELAT_1:30;
       then consider X being Filter of L such that
   A20: x = X by A5,A6;
       consider Y being Filter of L such that
   A21: y = Y by A5,A6,A19;
      X c= Y by A4,A5,A17,A18,A19,A20,A21,WELLORD2:def 1;
   then p in rBP by A1,A2,A18,A20,A21,WELLORD2:def 1;
     hence p in rBP|_2 cIP by A16,A17,XBOOLE_0:def 3;
    end;
    assume p in rBP|_2 cIP;
   then A22: p in rBP & p in [:cIP, cIP:] by A16,XBOOLE_0:def 3;
       then consider x, y being set such that
   A23: x in cIP & y in cIP & p = [x, y] by ZFMISC_1:def 2;
       consider X being Filter of L such that
   A24: x = X by A4,A6,A23;
       consider Y being Filter of L such that
   A25: y = Y by A4,A6,A23;
         x c= y by A1,A2,A22,A23,A24,A25,WELLORD2:def 1;
    hence p in rIP by A4,A23,WELLORD2:def 1;
  end;
  then rIP = rBP|_2 cIP by TARSKI:2;
 then reconsider IP as full SubRelStr of BP by YELLOW_0:def 14;
A26: IP is infs-inheriting proof let X be Subset of IP such that
         ex_inf_of X, BP;
     set sX = "/\"(X, BP);
    per cases;
    suppose X is empty;
    then A27:  "/\"(X, BP) = Top BP by YELLOW_0:def 12
                  .= cL by YELLOW_1:19;
           [#]L = cL by PRE_TOPC:12;
     hence "/\"(X, BP) in the carrier of IP by A4,A6,A27;
    suppose A28: X is non empty;
      X c= bool cL by A4,A7,XBOOLE_1:1;
         then reconsider X' = X as Subset of BP by A1,A2;
         reconsider F = X as Subset of bool cL by A4,A7,XBOOLE_1:1;
    A29: inf X' = meet X by A28,YELLOW_1:20;
        reconsider sX as Subset of L by A3;
          for Y being set st Y in X holds Top L in Y proof
         let Y be set;
         assume Y in X;
         then Y in Filt L by A4;
         then consider Z being Filter of L such that
     A30: Y = Z by A6;
         thus Top L in Y by A30,WAYBEL_4:22;
        end;
    then A31: sX is non empty by A28,A29,SETFAM_1:def 1;
    A32: for X being Subset of L st X in F holds X is upper filtered proof
         let X be Subset of L such that
        A33: X in F; X in Filt L by A4,A33;
            then consider Y being Filter of L such that
        A34: X = Y by A6;
         thus X is upper filtered by A34;
        end;
        then for X being Subset of L st X in F holds X is upper;
    then A35: sX is upper by A29,YELLOW_2:39;
          sX is filtered by A29,A32,YELLOW_2:41;
      hence "/\"(X, BP) in the carrier of IP by A4,A6,A31,A35;
   end;
    IP is directed-sups-inheriting proof
   let X be directed Subset of IP such that
  A36: X <> {} & ex_sup_of X, BP;
     set sX = "\/"(X, BP);
      X c= bool cL by A4,A7,XBOOLE_1:1;
         then reconsider X' = X as Subset of BP by A1,A2;
         reconsider F = X as Subset of bool cL by A4,A7,XBOOLE_1:1;
    A37: sup X' = union X by YELLOW_1:21;
        reconsider sX as Subset of L by A3;
         consider Y being set such that
     A38: Y in X by A36,XBOOLE_0:def 1;
           Y in Filt L by A4,A38;
         then consider Z being Filter of L such that
     A39: Y = Z by A6;
          Top L in Y by A39,WAYBEL_4:22;
    then A40: sX is non empty by A37,A38,TARSKI:def 4;
    A41: for X being Subset of L st X in F holds X is upper filtered proof
         let X be Subset of L;
         assume X in F;
            then X in Filt L by A4;
            then consider Y being Filter of L such that
        A42: X = Y by A6;
         thus X is upper filtered by A42;
        end;
        then for X being Subset of L st X in F holds X is upper;
    then A43: sX is upper by A37,WAYBEL_0:28;
    A44: for X being Subset of L st X in F holds X is filtered by A41;
          for P, R being Subset of L st P in F & R in F
          ex Z being Subset of L st Z in F & P \/ R c= Z proof
          let P, R be Subset of L; assume
        A45: P in F & R in F;
           then reconsider P' = P, R' = R as Element of IP;
           consider Z being Element of IP such that
        A46: Z in X & P' <= Z & R' <= Z by A45,WAYBEL_0:def 1;
              Z in the carrier of IP by A46;
           then consider Z' being Filter of L such that
        A47: Z' = Z by A4,A6;
          take Z';
          thus Z' in F by A46,A47;
              P' c= Z & R' c= Z by A46,YELLOW_1:3;
          hence P \/ R c= Z' by A47,XBOOLE_1:8;
        end;
        then sX is filtered by A37,A44,WAYBEL_0:47;
   hence "\/"(X,BP) in the carrier of IP by A4,A6,A40,A43;
  end;
 hence InclPoset Filt L is CLSubFrame of BP by A26;
end;

definition
 let L be upper-bounded with_infima non empty Poset;
 cluster InclPoset Filt L -> continuous;
 coherence proof
     InclPoset Filt L is CLSubFrame of BoolePoset the carrier of L by Th6;
  hence InclPoset Filt L is continuous by WAYBEL_5:28;
 end;
end;

definition
 let L be upper-bounded non empty Poset;
 cluster -> non empty Element of InclPoset Filt L;
 coherence proof let x be Element of InclPoset Filt L;
     InclPoset Filt L = RelStr(#Filt L, RelIncl Filt L#) by YELLOW_1:def 1;
   then x in Filt L;
   then x in {X where X is Filter of L: not contradiction} by WAYBEL_0:def 24;
   then consider X being Filter of L such that
A1: x = X;
  thus x is non empty by A1;
 end;
end;

begin :: Free generators of continuous lattices

definition :: replaces :: WAYBEL16:def 2
 let S be continuous complete (non empty Poset);
 let A be set;
 pred A is_FreeGen_set_of S means :Def1:
  for T be continuous complete (non empty Poset)
   for f be Function of A, the carrier of T
    ex h be CLHomomorphism of S, T st
     h|A = f & for h' being CLHomomorphism of S,T st h'|A = f holds h' = h;
end;

theorem Th7:
 for S being continuous complete (non empty Poset), A being set
  st A is_FreeGen_set_of S holds A is Subset of S
proof let S be continuous complete (non empty Poset), A be set such that
A1: A is_FreeGen_set_of S;
  consider T being continuous complete (non empty Poset);
  consider f being Function of A, the carrier of T;
  consider h being CLHomomorphism of S, T such that
A2: h|A = f and
     for h' being CLHomomorphism of S, T st h'|A = f holds h' = h by A1,Def1;
 A3: dom f = A by FUNCT_2:def 1;
 A4: dom h = the carrier of S by FUNCT_2:def 1;
       dom (h|A) = dom h /\ A by RELAT_1:90;
   then A c= the carrier of S by A2,A3,A4,XBOOLE_1:17;
 hence A is Subset of S;
end;

theorem Th8:
 for S being continuous complete (non empty Poset), A being set
  st A is_FreeGen_set_of S
   for h' being CLHomomorphism of S, S st h'|A = id A holds h' = id S
proof let S be continuous complete (non empty Poset), A be set such that
A1: A is_FreeGen_set_of S; set L = S;
   A2: A is Subset of L by A1,Th7;
      dom id A = A & rng id A = A by RELAT_1:71;
   then reconsider f = id A as Function of A,the carrier of L
      by A2,FUNCT_2:def 1,RELSET_1:11;
   consider h being CLHomomorphism of L, L such that
     h|A = f and
A3: for h' being CLHomomorphism of L,L st h'|A = f holds h' = h by A1,Def1;
 let h' be CLHomomorphism of S, S such that
A4: h'|A = id A;
A5: id L is CLHomomorphism of L, L by Th5;
     id L = id the carrier of L by GRCAT_1:def 11;
then A6: (id L)|A = id A by A2,FUNCT_3:1;
 thus h' = h by A3,A4
        .= id L by A3,A5,A6;
end;

begin :: Representation theorem for free continuous lattices

  reserve X for set,
          F for Filter of BoolePoset X,
          x for Element of BoolePoset X,
          z for Element of X;

definition :: See proof of Theorem 4.17, p. 90
 let X;
 func FixedUltraFilters X -> Subset-Family of BoolePoset X equals :Def2:
   { uparrow x : ex z st x = {z} };
 coherence proof
  set FUF = { uparrow x where x is Element of BoolePoset X :
       ex y being Element of X st x = {y} };
     FUF c= bool the carrier of BoolePoset X proof let z be set; assume
      z in FUF; then consider x being Element of BoolePoset X such that
   A1: z = uparrow x & ex y being Element of X st x = {y};
    thus z in bool the carrier of BoolePoset X by A1;
   end;
  then FUF is Subset-Family of BoolePoset X by SETFAM_1:def 7;
  hence FUF is Subset-Family of BoolePoset X;
 end;
end;

theorem Th9:
 FixedUltraFilters X c= Filt BoolePoset X
proof
A1: FixedUltraFilters X = { uparrow x : ex z st x = {z} } by Def2;
  let F be set; assume F in FixedUltraFilters X;
   then consider x being Element of BoolePoset X such that
A2: F = uparrow x and
     ex y being Element of X st x = {y} by A1;
     F in {Z where Z is Filter of BoolePoset X : not contradiction} by A2;
 hence F in Filt BoolePoset X by WAYBEL_0:def 24;
end;

theorem Th10:
 Card FixedUltraFilters X = Card X
proof set FUF = { uparrow x : ex z st x = {z} };
A1: FUF = FixedUltraFilters X by Def2;
  A2: BoolePoset X = InclPoset bool X by YELLOW_1:4;
      A3: InclPoset bool X = RelStr(#bool X, RelIncl bool X#)
           by YELLOW_1:def 1;
then A4: the carrier of BoolePoset X = bool X by YELLOW_1:4;
    X,FUF are_equipotent proof
   defpred P[set, set] means
    ex y being Element of X, x being Element of BoolePoset X
     st x = {y} & $1 = y & $2 = uparrow x;
A5: for x,y1,y2 being set st x in X & P[x,y1] & P[x,y2] holds y1 = y2;
A6: for x being set st x in X ex y being set st P[x,y] proof
     let x be set; assume
   A7: x in X;
       then reconsider x' = x as Element of X;
         {x} c= X by A7,ZFMISC_1:37;
       then reconsider bx = {x} as Element of BoolePoset X by A2,A3;
     take uparrow bx; take x'; take bx; thus thesis;
    end;
   consider f being Function such that
A8: dom f = X & for x being set st x in X holds P[x, f.x] from FuncEx(A5,A6);
   take f;
   thus f is one-to-one proof
    let x1, x2 be set such that
 A9: x1 in dom f & x2 in dom f and
 A10: f.x1 = f.x2;
     consider x1' being Element of X, bx1 being Element of BoolePoset X
        such that
 A11: bx1 = {x1'} & x1 = x1' & f.x1 = uparrow bx1 by A8,A9;
     consider x2' being Element of X, bx2 being Element of BoolePoset X
        such that
 A12: bx2 = {x2'} & x2 = x2' & f.x2 = uparrow bx2 by A8,A9;
       bx1 = bx2 by A10,A11,A12,WAYBEL_0:20;
    hence x1 = x2 by A11,A12,ZFMISC_1:6;
   end;
   thus dom f = X by A8;
      now let z be set;
     hereby assume z in rng f; then consider x1 being set such that
     A13: x1 in dom f & z = f.x1 by FUNCT_1:def 5;
         consider x1' being Element of X, bx1 being Element of BoolePoset X
        such that
     A14: bx1 = {x1'} & x1 = x1' & f.x1 = uparrow bx1 by A8,A13;
      thus z in FUF by A13,A14;
     end;
     assume z in FUF;
         then consider bx being Element of BoolePoset X such that
     A15: z = uparrow bx & ex y being Element of X st bx = {y};
         consider y being Element of X such that
     A16: bx = {y} by A15;
     A17: y in X by A4,A16,ZFMISC_1:37;
         then consider x1' being Element of X, bx1 being Element of BoolePoset
X
               such that
     A18: bx1 = {x1'} & y = x1' & f.y = uparrow bx1 by A8;
     thus z in rng f by A8,A15,A16,A17,A18,FUNCT_1:def 5;
    end;
   hence rng f = FUF by TARSKI:2;
  end;
 hence Card FixedUltraFilters X = Card X by A1,CARD_1:21;
end;

theorem Th11:
F = "\/"({"/\"({uparrow x : ex z st x = {z} & z in Y},
           InclPoset Filt BoolePoset X) where Y is Subset of X : Y in F},
        InclPoset Filt BoolePoset X)
proof set BP = BoolePoset X; set IP = InclPoset Filt BP;
 set cIP = the carrier of IP;
 set Xs = {"/\"({uparrow x : ex z st x = {z} & z in Y }, IP
               ) where Y is Subset of X : Y in F};
 set RS = "\/"(Xs, IP);
     A1: InclPoset Filt BP = RelStr(#Filt BP, RelIncl Filt BP#)
             by YELLOW_1:def 1;
A2: the carrier of BP = the carrier of LattPOSet BooleLatt X
         by YELLOW_1:def 2
  .= the carrier of RelStr(#the carrier of BooleLatt X,
             LattRel BooleLatt X#) by LATTICE3:def 2
  .= bool X by LATTICE3:def 1;
A3: Xs c= cIP proof let p be set; assume p in Xs;
     then consider YY being Subset of X such that
    A4: p = "/\"({uparrow x : ex z st x = {z} & z in YY}, IP) and YY in F;
     thus p in cIP by A4;
    end;
      now consider YY being set such that
    A5: YY in F by XBOOLE_0:def 1;
        "/\"({uparrow x : ex z st x = {z} & z in YY}, IP) in Xs by A2,A5;
     hence Xs is non empty;
    end;
 then reconsider Xs' = Xs as non empty Subset of IP by A3;
A6: ex_sup_of Xs', IP by YELLOW_0:17;
A7: Filt BP = { FF where FF is Filter of BP : not contradiction }
          by WAYBEL_0:def 24;
     then F in Filt BP;
  then reconsider F' = F as Element of IP by A1;
     F c= RS proof let p be set; assume
   A8: p in F;
       then reconsider Y = p as Element of F;
       set Xsi = {uparrow x where x is Element of BP :
                 ex z being Element of X st x = {z} & z in Y};
   A9: "/\"(Xsi, IP) in Xs by A2;
    per cases;
    suppose Xsi is empty;
    then A10: "/\"(Xsi, IP) = Top IP by YELLOW_0:def 12 .= bool X by WAYBEL16:
15;
          Xs' is_<=_than RS by A6,YELLOW_0:def 9;
        then "/\"(Xsi, IP) <= RS by A9,LATTICE3:def 9;
    then A11: bool X c= RS by A10,YELLOW_1:3;
          p in the carrier of BP by A8;
     hence p in RS by A2,A11;
    suppose A12: Xsi is non empty;
          Xsi c= cIP proof let r be set; assume r in Xsi;
          then consider xz being Element of BP such that
        A13: r = uparrow xz and
               ex z being Element of X st xz = {z} & z in Y;
         thus r in cIP by A1,A7,A13;
        end;
       then reconsider Xsi as non empty Subset of IP by A12;
   A14: "/\"(Xsi, IP) = meet Xsi by WAYBEL16:10;
         for yy being set st yy in Xsi holds Y in yy proof
         let yy be set; assume yy in Xsi;
         then consider r being Element of BP such that
       A15: yy = uparrow r and
       A16: ex z being Element of X st r = {z} & z in Y;
           reconsider Y' = Y as Element of BP;
             r c= Y by A16,ZFMISC_1:37; then r <= Y' by YELLOW_1:2;
         hence Y in yy by A15,WAYBEL_0:18;
       end; then Y in meet Xsi by SETFAM_1:def 1;
   then A17: p in union Xs by A9,A14,TARSKI:def 4;
         union Xs' c= RS by A6,WAYBEL16:17;
      hence p in RS by A17;
   end;
then A18: F' <= RS by YELLOW_1:3;
     Xs is_<=_than F' proof let b be Element of IP; assume b in Xs;
      then consider Y being Subset of X such that
   A19: b = "/\"({uparrow x : ex z st x = {z} & z in Y}, IP) and
   A20: Y in F;
      reconsider Y' = Y as Element of F by A20;
      set Xsi = {uparrow x : ex z st x = {z} & z in Y};
    per cases;
    suppose A21: Y is empty;
        now assume Xsi is non empty; then consider p being set such that
      A22: p in Xsi by XBOOLE_0:def 1;
          consider x being Element of BP such that
            p = uparrow x and
      A23: ex z being Element of X st x = {z} & z in Y by A22;
          consider z being Element of X such that
      A24: x = {z} & z in Y by A23;
       thus contradiction by A21,A24;
      end;
    then A25: "/\"(Xsi, IP) = Top IP by YELLOW_0:def 12 .= bool X by WAYBEL16:
15;
          Bottom BP = {} by YELLOW_1:18;
        then uparrow Bottom BP c= F by A20,A21,WAYBEL11:42;
    then bool X c= F by A2,WAYBEL14:10;
     hence b <= F' by A2,A19,A25,XBOOLE_0:def 10;
    suppose A26: Y is non empty;
    A27: now consider z being set such that
        A28: z in Y by A26,XBOOLE_0:def 1;
            reconsider z as Element of X by A28; {z} c= X by A28,ZFMISC_1:37;
            then reconsider x = {z} as Element of BP by A2;
 uparrow x in Xsi by A28;
          hence Xsi is non empty;
        end;
          Xsi c= cIP proof let r be set; assume r in Xsi;
          then consider xz being Element of BP such that
        A29: r = uparrow xz and
               ex z being Element of X st xz = {z} & z in Y;
         thus r in cIP by A1,A7,A29;
        end;
       then reconsider Xsi as non empty Subset of IP by A27;
   A30: "/\"(Xsi, IP) = meet Xsi by WAYBEL16:10;
         b c= F' proof let yy be set; assume
       A31:  yy in b;
             b in Filt BP by A1;
           then consider bf being Filter of BP such that
       A32: b = bf by A7;
           reconsider yy' = yy as Element of bf by A31,A32;
           reconsider yy' as Element of BP;
       A33: uparrow Y' c= F' by WAYBEL11:42;
             Y c= yy' proof let zz be set; assume
         A34: zz in Y;
             then reconsider z = zz as Element of X;
               {z} c= X by A34,ZFMISC_1:37;
             then reconsider xz = {z} as Element of BP by A2;
 uparrow xz in Xsi by A34;
             then yy in uparrow xz by A19,A30,A31,SETFAM_1:def 1; then xz <=
yy' by WAYBEL_0:18;
             then {z} c= yy by YELLOW_1:2;
            hence zz in yy' by ZFMISC_1:37;
           end; then Y' <= yy' by YELLOW_1:2;
         then yy in uparrow Y' by WAYBEL_0:18;
        hence yy in F' by A33;
       end;
    hence b <= F' by YELLOW_1:3;
   end; then RS <= F' by A6,YELLOW_0:def 9;
 hence F = RS by A18,YELLOW_0:def 3;
end;

definition :: See proof of Theorem 4.17, p. 90
 let X; let L be continuous complete (non empty Poset);
 let f be Function of FixedUltraFilters X, the carrier of L;
 func f-extension_to_hom -> map of InclPoset Filt BoolePoset X, L means
:Def3:
 for Fi being Element of InclPoset Filt BoolePoset X holds
  it.Fi = "\/"({"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                  }, L) where Y is Subset of X : Y in Fi
              }, L);
 existence proof
 set IP = InclPoset Filt BoolePoset X;
 deffunc F(Element of IP) =
    "\/"({"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                  }, L) where Y is Subset of X : Y in $1
              }, L);
 consider F being Function of the carrier of IP, the carrier of L such that
A1: for Fi being Element of IP holds F.Fi = F(Fi) from LambdaD;
 reconsider F as map of IP, L;
 take F;
 thus thesis by A1;
 end;
 uniqueness proof
 set IP = InclPoset Filt BoolePoset X;
  let it1, it2 be map of IP, L such that
A2: for Fi being Element of IP holds
    it1.Fi = "\/"({"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                  }, L) where Y is Subset of X : Y in Fi
              }, L) and
A3: for Fi being Element of IP holds
    it2.Fi = "\/"({"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                  }, L) where Y is Subset of X : Y in Fi
              }, L);
    reconsider it1' = it1 as Function of the carrier of IP, the carrier of L;
    reconsider it2' = it2 as Function of the carrier of IP, the carrier of L;
      now let Fi be Element of IP;
    thus it1'.Fi = "\/"({"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                  }, L) where Y is Subset of X : Y in Fi
              }, L) by A2
               .= it2'.Fi by A3;
    end;
 hence it1 = it2 by FUNCT_2:113;
 end;
end;

theorem
   for L being continuous complete (non empty Poset),
     f being Function of FixedUltraFilters X, the carrier of L
  holds f-extension_to_hom is monotone
proof let L be continuous complete (non empty Poset),
          f be Function of FixedUltraFilters X, the carrier of L;
    let F1, F2 be Element of InclPoset Filt BoolePoset X; assume
    F1 <= F2;
then A1: F1 c= F2 by YELLOW_1:3;
 set F = f-extension_to_hom;
  let FF1, FF2 be Element of L such that
A2: FF1 = F.F1 & FF2 = F.F2;
A3: F.F1 = "\/"({"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                  }, L) where Y is Subset of X : Y in F1}, L) by Def3;
A4: F.F2 = "\/"({"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                  }, L) where Y is Subset of X : Y in F2}, L) by Def3;
   set F1s = {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                  }, L) where Y is Subset of X : Y in F1};
   set F2s = {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                  }, L) where Y is Subset of X : Y in F2 };
A5: ex_sup_of F1s, L by YELLOW_0:17;
A6: ex_sup_of F2s, L by YELLOW_0:17;
     F1s c= F2s proof let s be set; assume s in F1s;
     then consider Y being Subset of X such that
   A7: s = "/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L) and
   A8: Y in F1;
    thus s in F2s by A1,A7,A8;
   end;
 hence FF1 <= FF2 by A2,A3,A4,A5,A6,YELLOW_0:34;
end;

theorem Th13:
 for L being continuous complete (non empty Poset),
     f being Function of FixedUltraFilters X, the carrier of L
   holds (f-extension_to_hom).Top (InclPoset Filt BoolePoset X) = Top L
proof let L be continuous complete (non empty Poset),
          f be Function of FixedUltraFilters X, the carrier of L;
 set IP = InclPoset Filt BoolePoset X;
 set F = f-extension_to_hom;
   reconsider T = Top IP as Element of IP;
A1: F.T = "\/"({"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                }, L) where Y is Subset of X : Y in T}, L) by Def3;
A2: T = bool X by WAYBEL16:15;
   reconsider E = {} as Subset of X by XBOOLE_1:2;
   set Z = {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                }, L) where Y is Subset of X : Y in T};
   A3: "/\"({f.(uparrow x) : ex z st x = {z} & z in E}, L) in Z by A2;
A4: {f.(uparrow x) : ex z st x = {z} & z in E} = {} proof
     assume not thesis; then consider r being set such that
    A5: r in {f.(uparrow x) : ex z st x = {z} & z in E} by XBOOLE_0:def 1;
      consider x such that r = f.(uparrow x) and
    A6: ex z st x = {z} & z in E by A5;
     thus contradiction by A6;
    end;
    A7: "/\"({}, L) = Top L by YELLOW_0:def 12;
     Z is_<=_than "\/"(Z, L) by YELLOW_0:32;
   then Top L <= "\/"(Z, L) by A3,A4,A7,LATTICE3:def 9;
 hence F.Top IP = Top L by A1,WAYBEL15:5;
end;

definition :: See proof of Theorem 4.17, p. 91
 let X; let L be continuous complete (non empty Poset),
     f be Function of FixedUltraFilters X, the carrier of L;
 cluster f-extension_to_hom -> directed-sups-preserving;
 coherence proof
 set IP = InclPoset Filt BoolePoset X;
 set F = f-extension_to_hom;
 let Fs be Subset of IP such that
A1: Fs is non empty directed; assume ex_sup_of Fs, IP;
 thus ex_sup_of F.:Fs, L by YELLOW_0:17;
A2: sup Fs = union Fs by A1,Th1;
 reconsider Fs' = Fs as non empty Subset of IP by A1;
 reconsider sFs = sup Fs as Element of IP;
A3: F.sFs = "\/"({"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
             }, L) where Y is Subset of X : Y in sFs }, L) by Def3;
   set FFs = {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                 }, L) where Y is Subset of X : Y in sFs };
  set FFsU = {{"/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L)
                   where Y is Subset of X : Y in YY
              } where YY is Element of Fs' : not contradiction
             };
   set Zs = {sup Z where Z is Subset of L : Z in FFsU};
     FFsU c= bool the carrier of L proof let r be set; assume r in FFsU;
     then consider YY being Element of Fs' such that
   A4: r = {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L)
                   where Y is Subset of X : Y in YY};
        r c= the carrier of L proof let s be set; assume s in r;
        then consider Y being Subset of X such that
      A5: s = "/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L) and
            Y in YY by A4;
       thus thesis by A5;
      end;
     hence r in bool the carrier of L;
   end;
then A6: "\/"(union FFsU, L) = "\/"(Zs, L) by Lm2;
     now let p be set;
    hereby assume p in FFs; then consider Y being Subset of X such that
    A7: p = "/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L) and
    A8: Y in sFs;
        consider YY being set such that
    A9: Y in YY and
    A10: YY in Fs by A2,A8,TARSKI:def 4;
    A11: p in {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y1}, L)
                   where Y1 is Subset of X : Y1 in YY} by A7,A9;
          {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y1}, L)
                   where Y1 is Subset of X : Y1 in YY} in FFsU by A10;
     hence p in union FFsU by A11,TARSKI:def 4;
    end;
    assume p in union FFsU; then consider r being set such that
    A12: p in r and
    A13: r in FFsU by TARSKI:def 4;
        consider YY being Element of Fs' such that
    A14: r = {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L)
                   where Y is Subset of X: Y in YY} by A13;
        consider Y being Subset of X such that
    A15: p = "/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L) and
    A16: Y in YY by A12,A14;
          Y in sFs by A2,A16,TARSKI:def 4;
    hence p in FFs by A15;
   end;
then A17: FFs = union FFsU by TARSKI:2;
    now let r be set;
   hereby assume r in F.:Fs; then consider YY being set such that
   A18: YY in the carrier of IP and
   A19: YY in Fs and
   A20: F.YY = r by FUNCT_2:115;
      reconsider YY as Element of Fs by A19;
      reconsider YY' = YY as Element of IP by A18;
   A21: F.YY' = "\/"({"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
               }, L) where Y is Subset of X : Y in YY'}, L) by Def3;
      set Zi = {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L)
                 where Y is Subset of X : Y in YY' };
        Zi c= the carrier of L proof let t be set; assume t in Zi;
       then consider Y being Subset of X such that
      A22: t = "/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L) and
            Y in YY';
       thus t in the carrier of L by A22;
      end;
      then reconsider Zi as Subset of L;
        Zi in FFsU;
    hence r in Zs by A20,A21;
   end;
   assume r in Zs; then consider Z being Subset of L such that
   A23: r = sup Z and
   A24: Z in FFsU;
       consider YY being Element of Fs such that
   A25: Z = {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L)
                   where Y is Subset of X : Y in YY} by A24;
      reconsider YY as Element of Fs';
      reconsider YY' = YY as Element of IP;
     F.YY' = "\/"({"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
               }, L) where Y is Subset of X : Y in YY'}, L) by Def3;
   hence r in F.:Fs by A23,A25,FUNCT_2:43;
  end;
 hence sup (F.:Fs) = F.sup Fs by A3,A6,A17,TARSKI:2;
end;
end;

Lm3:
 for X be with_non-empty_elements set holds
  id X is non-empty ManySortedSet of X;

definition :: See proof of Theorem 4.17, p. 91
 let X; let L be continuous complete (non empty Poset),
     f be Function of FixedUltraFilters X, the carrier of L;
 cluster f-extension_to_hom -> infs-preserving;
 coherence proof
 set BP = BoolePoset X; set IP = InclPoset Filt BP;
 set F = f-extension_to_hom;
 set cIP = the carrier of IP; set cL = the carrier of L;
 set FUF = FixedUltraFilters X;
A1: FUF = { uparrow x where x is Element of BoolePoset X :
               ex y being Element of X st x = {y} } by Def2;
   A2: InclPoset Filt BP = RelStr(#Filt BP, RelIncl Filt BP#)
      by YELLOW_1:def 1;
A3: Filt BP = { FF where FF is Filter of BP : not contradiction }
          by WAYBEL_0:def 24;
  A4: BoolePoset X = InclPoset bool X by YELLOW_1:4;
      A5: InclPoset bool X = RelStr(#bool X, RelIncl bool X#)
           by YELLOW_1:def 1;
then A6: the carrier of BoolePoset X = bool X by YELLOW_1:4;
  let Fs be Subset of IP;
  assume ex_inf_of Fs, IP;
  thus ex_inf_of F.:Fs, L by YELLOW_0:17;
  per cases;
  suppose A7: Fs is empty;
  then A8: "/\"(F.:Fs, L) = "/\"({}, L) by RELAT_1:149
      .= Top L by YELLOW_0:def 12;
      "/\"(Fs, IP) = Top IP by A7,YELLOW_0:def 12;
   hence inf (F.:Fs) = F.inf Fs by A8,Th13;
  suppose Fs is non empty;
   then reconsider Fs' = Fs as non empty Subset of IP;
     now assume {} in Fs'; then {} is Element of Fs';
     then {} is Element of IP;
    hence contradiction;
   end;
   then Fs' is with_non-empty_elements by AMI_1:def 1;
   then reconsider K = id Fs' as non-empty ManySortedSet of Fs' by Lm3;
   defpred P[set, set, set] means
      $1 = "/\"({f.(uparrow x) : ex z st x = {z} & z in $2}, L);
A9: for i be set st i in Fs' holds
     for s be set st s in K.i ex y be set st y in (Fs' --> cL).i &
                     P[y, s, i] proof
     let i be set such that
    A10: i in Fs';
     let s be set such that s in K.i;
     take y = "/\"({f.(uparrow x) : ex z st x = {z} & z in s}, L);
        y in cL;
     hence y in (Fs' --> cL).i by A10,FUNCOP_1:13;
     thus P[y, s, i];
    end;
  consider FD being ManySortedFunction of K, (Fs' --> cL) such that
A11: for i being set st i in Fs' holds
    ex g being Function of K.i, (Fs' --> cL).i st g = FD.i &
     for s being set st s in K.i holds P[g.s, s, i] from MSFExFunc(A9);
A12: dom FD = Fs' by PBOOLE:def 3;
  deffunc FDi(Element of Fs')
   = {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                 }, L) where Y is Subset of X : Y in $1};
  defpred rFD[Element of Fs'] means rng (FD.$1) = FDi($1);
A13: for s being Element of Fs' holds rFD[s] proof
    let s be Element of Fs';
       now let t be set;
      hereby assume t in rng (FD.s);
        then consider u being set such that
      A14: u in dom (FD.s) and
      A15: t = (FD.s).u by FUNCT_1:def 5;
      A16: dom (FD.s) = K.s by FUNCT_2:def 1;
          consider g being Function of K.s, (Fs' --> cL).s such that
      A17: g = FD.s and
      A18: for u being set st u in K.s holds P[g.u, u, s] by A11;
      A19: g.u = "/\"({f.(uparrow x) : ex z st x = {z} & z in u}, L)
             by A14,A16,A18;
      A20: K.s = s by FUNCT_1:35;
            s in cIP; then consider FF being Filter of BP such that
      A21: s = FF by A2,A3;
          reconsider u as Subset of X by A5,A14,A16,A20,A21,YELLOW_1:4;
            u in s by A14,A16,FUNCT_1:35;
       hence t in FDi(s) by A15,A17,A19;
      end;
     assume t in FDi(s); then consider Y being Subset of X such that
     A22: t = "/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L) and
     A23: Y in s;
     A24: dom (FD.s) = K.s by FUNCT_2:def 1;
     A25: K.s = s by FUNCT_1:35;
     A26: Y in dom (FD.s) by A23,A24,FUNCT_1:35;
         consider g being Function of K.s, (Fs' --> cL).s such that
     A27: g = FD.s and
     A28: for u being set st u in K.s holds P[g.u, u, s] by A11;
        g.Y = "/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L)
             by A23,A25,A28;
     hence t in rng (FD.s) by A22,A26,A27,FUNCT_1:def 5;
     end;
    hence rFD[s] by TARSKI:2;
   end;
   reconsider FD as DoubleIndexedSet of K, L;
     now let r be set;
    hereby assume r in F.:Fs; then consider s being set such that
    A29: s in cIP and
    A30: s in Fs and
    A31: F.s = r by FUNCT_2:115;
        reconsider s' = s as Element of cIP by A29;
    A32: F.s' = "\/"({"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                         }, L) where Y is Subset of X : Y in s'
                    }, L) by Def3;
        reconsider s as Element of Fs' by A30;
          rFD[s] by A13;
        then r = Sup (FD.s) by A31,A32,YELLOW_2:def 5;
     hence r in rng Sups FD by WAYBEL_5:14;
    end;
    assume r in rng Sups FD;
      then consider s being Element of Fs' such that
    A33: r = Sup (FD.s) by WAYBEL_5:14;
      rFD[s] by A13;
    then F.s = "\/"(rng (FD.s), L) by Def3
           .= Sup (FD.s) by YELLOW_2:def 5;
    hence r in F.:Fs by A33,FUNCT_2:43;
   end;
   then F.:Fs = rng Sups FD by TARSKI:2;
then A34: inf (F.:Fs) = Inf Sups FD by YELLOW_2:def 6;
     for j being Element of Fs' holds rng(FD.j) is directed proof
    let j be Element of Fs';
    let k, m be Element of L; assume
   A35: k in rng(FD.j) & m in rng(FD.j);
       then consider kd being set such that
   A36: kd in dom (FD.j) and
   A37: FD.j.kd = k by FUNCT_1:def 5;
       consider md being set such that
   A38: md in dom (FD.j) and
   A39: FD.j.md = m by A35,FUNCT_1:def 5;
   A40: dom (FD.j) = K.j by FUNCT_2:def 1;
   A41: K.j = j by FUNCT_1:35;
         j in cIP; then consider FF being Filter of BP such that
   A42: j = FF by A2,A3;
       reconsider kd as Element of BP by A36,A40,A41,A42;
       reconsider md as Element of BP by A38,A40,A41,A42;
       consider nd being Element of BP such that
   A43: nd in FF & nd <= kd & nd <= md by A36,A38,A40,A41,A42,WAYBEL_0:def 2;
   A44: rng(FD.j) = FDi(j) by A13;
       set n = FD.j.nd;
         n in rng(FD.j) by A40,A41,A42,A43,FUNCT_1:def 5;
       then consider Y being Subset of X such that
   A45: n = "/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L) and
          Y in j by A44;
       reconsider n as Element of L by A45;
    take n;
    thus n in rng(FD.j) by A40,A41,A42,A43,FUNCT_1:def 5;
         consider g being Function of K.j, (Fs' --> cL).j such that
    A46: g = FD.j and
    A47: for u being set st u in K.j holds P[g.u, u, j] by A11;
         set kds = {f.(uparrow x) : ex z st x = {z} & z in kd};
    A48: g.kd = "/\"(kds, L) by A36,A40,A47;
         set nds = {f.(uparrow x) : ex z st x = {z} & z in nd};
    A49: g.nd = "/\"(nds, L) by A41,A42,A43,A47;
    A50: nd c= kd by A43,YELLOW_1:2;
    A51: ex_inf_of kds, L by YELLOW_0:17;
    A52: ex_inf_of nds, L by YELLOW_0:17;
           nds c= kds proof let w be set; assume w in nds;
           then consider x such that
         A53: w = f.(uparrow x) and
         A54: ex z st x = {z} & z in nd;
             consider z such that
         A55: x = {z} & z in nd by A54;
           thus w in kds by A50,A53,A55;
         end;
    hence k <= n by A37,A46,A48,A49,A51,A52,YELLOW_0:35;
         set mds = {f.(uparrow x) : ex z st x = {z} & z in md};
    A56: g.md = "/\"(mds, L) by A38,A40,A47;
    A57: nd c= md by A43,YELLOW_1:2;
    A58: ex_inf_of mds, L by YELLOW_0:17;
           nds c= mds proof let w be set; assume w in nds;
           then consider x such that
         A59: w = f.(uparrow x) and
         A60: ex z st x = {z} & z in nd;
             consider z such that
         A61: x = {z} & z in nd by A60;
           thus w in mds by A57,A59,A61;
         end;
    hence m <= n by A39,A46,A49,A52,A56,A58,YELLOW_0:35;
   end;
then A62: Inf Sups FD = Sup Infs Frege FD by WAYBEL_5:19
              .= "\/"(rng Infs Frege FD, L) by YELLOW_2:def 5;
     meet Fs' is Filter of BoolePoset X by WAYBEL16:9;
   then meet Fs' in Filt BP by A3;
   then reconsider mFs = meet Fs' as Element of cIP by A2;
A63: inf Fs' = meet Fs' by WAYBEL16:10;
   set smFs = {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y
                  }, L) where Y is Subset of X : Y in mFs};
A64: F.(meet Fs') = "\/"(smFs, L) by Def3;
     now let r be set;
    reconsider pdFD = product doms FD as non empty functional set;
    reconsider dFFD = product doms FD --> Fs' as ManySortedSet of pdFD;
    reconsider FFD = Frege FD as DoubleIndexedSet of dFFD, L;
 A65: dom FFD = pdFD by PBOOLE:def 3;

  deffunc rFFDs(Element of pdFD) =
     {"/\"({f.(uparrow x) : ex z st x = {z} & z in $1.u}, L)
                          where u is Element of Fs' : u in dom (FFD.$1) };
A66: now let s be Element of pdFD;
    A67: dom FD = dom (FFD.s) by A65,WAYBEL_5:8;
           now let t be set;
          hereby assume t in rng (FFD.s);
            then consider u being set such that
          A68: u in dom (FFD.s) and
          A69: t = FFD.s.u by FUNCT_1:def 5;
          A70: FFD.s.u = (FD.u).(s.u) by A65,A67,A68,WAYBEL_5:9;
              reconsider u as Element of Fs' by A67,A68,PBOOLE:def 3;
              consider g being Function of K.u, (Fs' --> cL).u such that
          A71: g = FD.u and
          A72: for v being set st v in K.u holds P[g.v, v, u] by A11;
             dom (FD.u) = K.u by FUNCT_2:def 1;
          then s.u in K.u by A12,A65,WAYBEL_5:9;
          then g.(s.u) = "/\"({f.(uparrow x) : ex z st x = {z} & z in s.u}, L)
                    by A72;
           hence t in rFFDs(s) by A68,A69,A70,A71;
          end;
           assume t in rFFDs(s);
             then consider u being Element of Fs' such that
          A73: t = "/\"({f.(uparrow x) : ex z st x = {z} & z in s.u}, L) and
          A74: u in dom (FFD.s);
              reconsider u as Element of Fs';
              consider g being Function of K.u, (Fs' --> cL).u such that
          A75: g = FD.u and
          A76: for v being set st v in K.u holds P[g.v, v, u] by A11;
             dom (FD.u) = K.u by FUNCT_2:def 1;
          then s.u in K.u by A12,A65,WAYBEL_5:9;
          then g.(s.u) = "/\"({f.(uparrow x) : ex z st x = {z} & z in s.u}, L)
                    by A76;
           hence t in rng(FFD.s) by A65,A67,A73,A74,A75,WAYBEL_5:9;
         end;
        hence rng (FFD.s) = rFFDs(s) by TARSKI:2;
       end; :: rFFDs
    hereby assume r in rng Infs Frege FD;
        then consider s being Element of pdFD such that
    A77: r = Inf (FFD.s) by WAYBEL_5:14;
    A78: dom FD = dom (FFD.s) by A65,WAYBEL_5:8;
    A79: dom s = dom FD by A65,WAYBEL_5:8;
          union rng s c= X proof let t be set; assume t in union rng s;
          then consider te being set such that
        A80: t in te & te in rng s by TARSKI:def 4;
          consider u being set such that
        A81: u in dom s & te = s.u by A80,FUNCT_1:def 5;
              FD.u is Function of K.u, cL by A12,A79,A81,WAYBEL_5:6;
         then dom (FD.u) = K.u by FUNCT_2:def 1
                      .= u by A12,A79,A81,FUNCT_1:34;
        then A82: te in u by A65,A79,A81,WAYBEL_5:9;
              u in cIP by A12,A79,A81; then consider FF being Filter of BP such
that
        A83: u = FF by A2,A3;
         thus t in X by A6,A80,A82,A83;
        end;
        then reconsider Y = union rng s as Subset of X;
        set Ys = {f.(uparrow x) : ex z st x = {z} & z in Y};
          now let Z be set; assume
        A84: Z in Fs';
            then Z in cIP; then consider FF being Filter of BP such that
        A85: Z = FF by A2,A3;
              s.Z in rng s by A12,A79,A84,FUNCT_1:def 5;
        then A86: s.Z c= Y by ZFMISC_1:92;
        A87: s.Z in dom (FD.Z) by A12,A65,A84,WAYBEL_5:9;
              FD.Z is Function of K.Z, cL by A84,WAYBEL_5:6;
        then A88: dom (FD.Z) = K.Z by FUNCT_2:def 1
                      .= Z by A84,FUNCT_1:34;
              s.Z c= X by A86,XBOOLE_1:1;
            then reconsider sZ = s.Z as Element of BP by A4,A5;
            reconsider Y' = Y as Element of BP by A4,A5;
              sZ <= Y' by A86,YELLOW_1:2;
         hence Y in Z by A85,A87,A88,WAYBEL_0:def 20;
        end;
        then Y in mFs by SETFAM_1:def 1;
    then A89: "/\"(Ys, L) in smFs;
    set idFFDs = {{f.(uparrow x) : ex z st x = {z} & z in s.u}
                  where u is Element of Fs' : u in dom (FFD.s)};
    A90: idFFDs c= bool the carrier of L proof let t be set; assume
            t in idFFDs; then consider u being Element of Fs' such that
        A91: t = {f.(uparrow x) : ex z st x = {z} & z in s.u} and
              u in dom (FFD.s);
              t c= cL proof let v be set; assume v in t;
              then consider x such that
            A92: v = f.(uparrow x) and
            A93: ex z st x = {z} & z in s.u by A91;
                consider z such that
            A94: x = {z} and z in s.u by A93;
                  uparrow x in FUF by A1,A94;
             hence v in cL by A92,FUNCT_2:7;
            end;
         hence t in bool cL;
        end;
          now let t be set;
         hereby assume t in rFFDs(s);
              then consider u being Element of Fs' such that
         A95: t = "/\"({f.(uparrow x) : ex z st x = {z} & z in s.u}, L) and
         A96: u in dom (FFD.s);
              {f.(uparrow x) : ex z st x = {z} & z in s.u} c= cL proof
              let v be set; assume
                  v in {f.(uparrow x) : ex z st x = {z} & z in s.u};
                then consider x such that
            A97: v = f.(uparrow x) and
            A98: ex z st x = {z} & z in s.u;
                consider z such that
            A99: x = {z} and
                  z in s.u by A98;
                  uparrow x in FUF by A1,A99;
             hence v in cL by A97,FUNCT_2:7;
            end;
            then reconsider Y1 ={f.(uparrow x) : ex z st x = {z} & z in s.u}
                    as Subset of L;
               Y1 in idFFDs by A96;
          hence t in {inf YY where YY is Subset of L : YY in idFFDs} by A95;
         end;
          assume t in {inf YY where YY is Subset of L : YY in idFFDs};
            then consider YY being Subset of L such that
          A100: t = inf YY and
          A101: YY in idFFDs;
              consider u1 being Element of Fs' such that
          A102: YY = {f.(uparrow x) : ex z st x = {z} & z in s.u1} and
          A103: u1 in dom (FFD.s) by A101;
          thus t in rFFDs(s) by A100,A102,A103;
        end;
    then A104: rFFDs(s) = {inf YY where YY is Subset of L : YY in idFFDs}
              by TARSKI:2;
    A105:  "/\"(rng (FFD.s), L) = "/\"(rFFDs(s), L) by A66
      .= "/\"(union idFFDs, L) by A90,A104,Lm1;
           now let t be set;
          hereby assume t in union idFFDs;
              then consider te being set such that
          A106: t in te and
          A107: te in idFFDs by TARSKI:def 4;
              consider u being Element of Fs' such that
          A108: te = {f.(uparrow x) : ex z st x = {z} & z in s.u} and
          A109: u in dom (FFD.s) by A107;
              consider x such that
          A110: t = f.(uparrow x) and
          A111: ex z st x = {z} & z in s.u by A106,A108;
              consider z such that
          A112: x = {z} & z in s.u by A111;
                s.u in rng s by A78,A79,A109,FUNCT_1:def 5;
              then z in Y by A112,TARSKI:def 4;
           hence t in Ys by A110,A112;
          end;
           assume t in Ys; then consider x such that
          A113: t = f.(uparrow x) and
          A114: ex z st x = {z} & z in Y;
              consider z such that
          A115: x = {z} & z in Y by A114;
              consider ze being set such that
          A116: z in ze & ze in rng s by A115,TARSKI:def 4;
              consider u being set such that
          A117: u in dom s & ze = s.u by A116,FUNCT_1:def 5;
              reconsider u as Element of Fs' by A79,A117,PBOOLE:def 3;
          A118: t in {f.(uparrow x1) where x1 is Element of BP :
                   ex z st x1 = {z} & z in s.u} by A113,A115,A116,A117;
                {f.(uparrow x1) where x1 is Element of BP :
                    ex z st x1 = {z} & z in s.u} in idFFDs by A78,A79,A117;
          hence t in union idFFDs by A118,TARSKI:def 4;
         end;
         then union idFFDs = Ys by TARSKI:2;
     hence r in smFs by A77,A89,A105,YELLOW_2:def 6;
    end;
    assume r in smFs; then consider Y being Subset of X such that
    A119: r = "/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L) and
    A120: Y in mFs;
        set s = Fs' --> Y;
        set s' = s;
    A121: dom doms FD = dom FD by EXTENS_1:3 .= dom s by A12,FUNCOP_1:19;
         now let w be set; assume
           w in dom doms FD;
        then A122: w in Fs' by A121,FUNCOP_1:19;
        then A123: (doms FD).w = dom (FD.w) by A12,FUNCT_6:31;
        A124: FD.w is Function of K.w, (Fs' --> cL).w by A122,MSUALG_1:def 2;
              (Fs' --> cL).w = cL by A122,FUNCOP_1:13;
        then A125: dom (FD.w) = K.w by A124,FUNCT_2:def 1 .= w by A122,FUNCT_1:
35;
              s.w = Y by A122,FUNCOP_1:13;
         hence s.w in (doms FD).w by A120,A122,A123,A125,SETFAM_1:def 1;
        end;
        then reconsider s as Element of pdFD by A121,CARD_3:18;
    A126: Inf (FFD.s) = "/\"(rng (FFD.s), L) by YELLOW_2:def 6;
    A127: rng (FFD.s) = rFFDs(s) by A66;
          now let t be set;
         hereby assume t in rFFDs(s);
           then consider u being Element of Fs' such that
         A128: t = "/\"({f.(uparrow x) : ex z st x = {z} & z in s.u}, L) and
               u in dom (FFD.s);
               s.u = Y by FUNCOP_1:13;
          hence t in {r} by A119,A128,TARSKI:def 1;
         end;
         assume t in {r};
         then A129: t = r by TARSKI:def 1;
             consider u being Element of Fs';
         A130: dom FD = dom (FFD.s) by A65,WAYBEL_5:8;
         A131: dom s = dom FD by A65,WAYBEL_5:8;
              A132: s' = s & dom s' = Fs' by FUNCOP_1:19;
               s.u = Y by FUNCOP_1:13;
         hence t in rFFDs(s) by A119,A129,A130,A131,A132;
        end;
    then A133: {"/\"({f.(uparrow x) : ex z st x = {z} & z in s.u}, L)
                          where u is Element of Fs' : u in dom (FFD.s) }
        = {r} by TARSKI:2;
          "/\"({r}, L) = r by A119,YELLOW_0:39;
    hence r in rng Infs Frege FD by A126,A127,A133,WAYBEL_5:14;
   end;
  hence inf (F.:Fs) = F.inf Fs by A34,A62,A63,A64,TARSKI:2;
 end;
end;

theorem Th14:
for L being continuous complete (non empty Poset),
    f being Function of FixedUltraFilters X, the carrier of L
 holds f-extension_to_hom | FixedUltraFilters X = f
proof let L be continuous complete (non empty Poset),
          f be Function of FixedUltraFilters X, the carrier of L;
 set FUF = FixedUltraFilters X;
A1: FUF = { uparrow x : ex z st x = {z} } by Def2;
 set BP = BoolePoset X;
 set IP = InclPoset Filt BP;
   A2: InclPoset Filt BP = RelStr(#Filt BP, RelIncl Filt BP#)
      by YELLOW_1:def 1;
A3: the carrier of BP = the carrier of LattPOSet BooleLatt X
         by YELLOW_1:def 2
  .= the carrier of RelStr(#the carrier of BooleLatt X,
             LattRel BooleLatt X#) by LATTICE3:def 2
  .= bool X by LATTICE3:def 1;
 set F = f-extension_to_hom;
    now
    dom F = the carrier of IP by FUNCT_2:def 1;
  then A4: FUF c= dom F by A2,Th9;
   hence FUF = dom (F|FUF) by RELAT_1:91;
   thus FUF = dom f by FUNCT_2:def 1;
   let xf be set; assume
  A5: xf in FUF;
      then consider xx being Element of BoolePoset X such that
  A6: xf = uparrow xx and
  A7: ex y being Element of X st xx = {y} by A1;
  A8: (F|FUF).xf = F.xf by A5,FUNCT_1:72;
      reconsider x' = xf as Element of IP by A4,A5,FUNCT_2:def 1
;
  set Xs = {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y }, L)
                    where Y is Subset of X : Y in x' };
  A9: ex_sup_of Xs, L by YELLOW_0:17;
      reconsider FUF' = FUF as non empty Subset-Family of BoolePoset X by A5;
      reconsider xf' = xf as Element of FUF' by A5;
      reconsider f' = f as Function of FUF', the carrier of L;
        f'.xf' is Element of L;
      then reconsider fxf = f.xf' as Element of L;
  A10: Xs is_<=_than fxf proof
       let b be Element of L; assume
        b in Xs;
         then consider Y being Subset of X such that
     A11: b = "/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L) and
     A12: Y in x';
         set Xsi = {f.(uparrow x) : ex z st x = {z} & z in Y };
         consider y being Element of X such that
     A13: xx = {y} by A7;
         reconsider Y as Element of BoolePoset X by A6,A12;
           xx <= Y by A6,A12,WAYBEL_0:18;
         then xx c= Y by YELLOW_1:2;
         then y in Y by A13,ZFMISC_1:37;
     then A14: fxf in Xsi by A6,A13;
           ex_inf_of Xsi, L by YELLOW_0:17;
         then Xsi is_>=_than b by A11,YELLOW_0:def 10;
       hence b <= fxf by A14,LATTICE3:def 8;
      end;
    for a being Element of L st Xs is_<=_than a holds fxf <= a proof
       let a be Element of L such that
     A15: Xs is_<=_than a;
           xx <= xx;
         then reconsider Y = xx as Element of x' by A6,WAYBEL_0:18;
         set Xsi = {f.(uparrow x) : ex z st x = {z} & z in Y };
         consider y being Element of X such that
     A16: xx = {y} by A7;
           now let p be set;
          hereby assume p in Xsi;
            then consider r being Element of BoolePoset X such that
         A17: p = f.(uparrow r) and
         A18: ex z being Element of X st r = {z} & z in Y;
            consider z being Element of X such that
         A19: r = {z} & z in Y by A18;
              xx = r by A16,A19,TARSKI:def 1;
           hence p in {fxf} by A6,A17,TARSKI:def 1;
          end;
          assume p in {fxf};
         then A20: p = fxf by TARSKI:def 1;
               y in Y by A16,TARSKI:def 1;
          hence p in Xsi by A6,A16,A20;
         end;
         then Xsi = {fxf} by TARSKI:2;
      then fxf = "/\"(Xsi, L) & Y in x' by YELLOW_0:39;
         then fxf in Xs by A3;
       hence fxf <= a by A15,LATTICE3:def 9;
      end;
      then f.xf = "\/"(Xs, L) by A9,A10,YELLOW_0:def 9;
   hence (F|FUF).xf = f.xf by A8,Def3;
  end;
 hence F|FUF = f by FUNCT_1:9;
end;

theorem Th15:
for L being continuous complete (non empty Poset),
    f being Function of FixedUltraFilters X, the carrier of L,
    h being CLHomomorphism of InclPoset Filt BoolePoset X, L
 st h | FixedUltraFilters X = f holds h = f-extension_to_hom
proof let L be continuous complete (non empty Poset),
          f be Function of FixedUltraFilters X, the carrier of L,
          h be CLHomomorphism of InclPoset Filt BoolePoset X, L; assume
A1: h | FixedUltraFilters X = f;
 set BP = BoolePoset X; set IP = InclPoset Filt BP;
 set cIP = the carrier of IP; set cL = the carrier of L;
 set F = f-extension_to_hom;
   A2: InclPoset Filt BP = RelStr(#Filt BP, RelIncl Filt BP#)
      by YELLOW_1:def 1;
A3: Filt BP = { FF where FF is Filter of BP : not contradiction }
          by WAYBEL_0:def 24;
A4: the carrier of BP = the carrier of LattPOSet BooleLatt X
         by YELLOW_1:def 2
  .= the carrier of RelStr(#the carrier of BooleLatt X,
             LattRel BooleLatt X#) by LATTICE3:def 2
  .= bool X by LATTICE3:def 1;
 reconsider h' = h as Function of cIP, cL;
 reconsider F' = F as Function of cIP, cL;
   now let Fi be Element of cIP;
     Fi in Filt BP by A2;
   then consider FF being Filter of BP such that
 A5: Fi = FF by A3;
 A6: FF = "\/"({"/\"({uparrow x : ex z st x = {z} & z in Y}, IP)
              where Y is Subset of X : Y in FF }, IP) by Th11;
 set Xs = {"/\"({uparrow x : ex z st x = {z} & z in Y}, IP)
              where Y is Subset of X : Y in FF };
 A7: h is infs-preserving & h is directed-sups-preserving by WAYBEL16:def 1;
 A8: Xs c= cIP proof let p be set; assume p in Xs;
     then consider YY being Subset of X such that
    A9: p = "/\"({uparrow x : ex z st x = {z} & z in YY}, IP) and
          YY in FF;
     thus p in cIP by A9;
    end;
      now consider YY being set such that
     A10: YY in FF by XBOOLE_0:def 1;
        "/\"({uparrow x : ex z st x = {z} & z in YY}, IP) in Xs by A4,A10;
     hence Xs is non empty;
    end;
     then reconsider Xs as non empty Subset of IP by A8;
   Xs is directed proof let a, b be Element of IP; assume
   A11: a in Xs & b in Xs;
       then consider Ya being Subset of X such that
   A12: a = "/\"({uparrow x : ex z st x = {z} & z in Ya}, IP) and
   A13: Ya in FF;
       reconsider Ya' = Ya as Element of FF by A13;
       consider Yb being Subset of X such that
   A14: b = "/\"({uparrow x : ex z st x = {z} & z in Yb}, IP) and
   A15: Yb in FF by A11;
       reconsider Yb' = Yb as Element of FF by A15;
       set Xsa = {uparrow x : ex z st x = {z} & z in Ya};
       set Xsb = {uparrow x : ex z st x = {z} & z in Yb};
      per cases;
      suppose Xsa is empty;
      then A16: "/\"(Xsa, IP) = Top IP by YELLOW_0:def 12;
       take a;
       thus a in Xs by A11;
       thus a <= a;
       thus b <= a by A12,A16,YELLOW_0:45;
      suppose Xsb is empty;
      then A17: "/\"(Xsb, IP) = Top IP by YELLOW_0:def 12;
       take b;
       thus b in Xs by A11;
       thus a <= b by A14,A17,YELLOW_0:45;
       thus b <= b;
      suppose A18: Xsa is non empty & Xsb is non empty;
          Xsa c= cIP proof let r be set; assume r in Xsa;
          then consider xz being Element of BP such that
        A19: r = uparrow xz and
               ex z st xz = {z} & z in Ya;
         thus r in cIP by A2,A3,A19;
        end;
       then reconsider Xsa as non empty Subset of IP by A18;
      A20: "/\"(Xsa, IP) = meet Xsa by WAYBEL16:10;
          Xsb c= cIP proof let r be set; assume r in Xsb;
          then consider xz being Element of BP such that
        A21: r = uparrow xz and
               ex z st xz = {z} & z in Yb;
         thus r in cIP by A2,A3,A21;
        end;
       then reconsider Xsb as non empty Subset of IP by A18;
      A22: "/\"(Xsb, IP) = meet Xsb by WAYBEL16:10;
        consider Yab being Element of BP such that
      A23: Yab in FF and
      A24: Yab <= Ya' and
      A25: Yab <= Yb' by WAYBEL_0:def 2;
        reconsider Yab as Element of FF by A23;
        set c = "/\"({uparrow x : ex z st x = {z} & z in Yab}, IP);
        set Xsc = {uparrow x : ex z st x = {z} & z in Yab};
      thus thesis proof
       per cases;
       suppose Xsc is empty;
      then A26: "/\"(Xsc, IP) = Top IP by YELLOW_0:def 12;
       take c;
       thus c in Xs by A4;
       thus a <= c by A26,YELLOW_0:45;
       thus b <= c by A26,YELLOW_0:45;
       suppose A27: Xsc is non empty;
          Xsc c= cIP proof let r be set; assume r in Xsc;
          then consider xz being Element of BP such that
        A28: r = uparrow xz and
               ex z st xz = {z} & z in Yab;
         thus r in cIP by A2,A3,A28;
        end;
       then reconsider Xsc as non empty Subset of IP by A27;
      A29: "/\"(Xsc, IP) = meet Xsc by WAYBEL16:10;
       take c;
       thus c in Xs by A4;
          a c= c proof let d be set; assume
        A30: d in a;
             Xsc c= Xsa proof let r be set; assume r in Xsc;
             then consider xz being Element of BP such that
           A31: r = uparrow xz and
           A32: ex z st xz = {z} & z in Yab;
               consider zz being Element of X such that
           A33: xz = {zz} and
           A34: zz in Yab by A32;
                 Yab c= Ya by A24,YELLOW_1:2;
            hence r in Xsa by A31,A33,A34;
           end;
           then meet Xsa c= meet Xsc by SETFAM_1:7;
         hence d in c by A12,A20,A29,A30;
        end;
       hence a <= c by YELLOW_1:3;
          b c= c proof let d be set; assume
        A35: d in b;
             Xsc c= Xsb proof let r be set; assume r in Xsc;
             then consider xz being Element of BP such that
           A36: r = uparrow xz and
           A37: ex z st xz = {z} & z in Yab;
               consider zz being Element of X such that
           A38: xz = {zz} and
           A39: zz in Yab by A37;
                 Yab c= Yb by A25,YELLOW_1:2;
            hence r in Xsb by A36,A38,A39;
           end;
           then meet Xsb c= meet Xsc by SETFAM_1:7;
         hence d in c by A14,A22,A29,A35;
        end;
       hence b <= c by YELLOW_1:3;
      end;
     end;
 then A40: h preserves_sup_of Xs by A7,WAYBEL_0:def 37;
 A41: ex_sup_of Xs, IP by YELLOW_0:17;
  set Xsf = {"/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L)
                  where Y is Subset of X : Y in FF };
  set FUF = FixedUltraFilters X;
A42: FUF = { uparrow x : ex z st x = {z} } by Def2;
    now let s be set;
   hereby assume s in h.:Xs;
     then consider t being set such that
         t in the carrier of IP and
   A43: t in Xs and
   A44: s = h.t by FUNCT_2:115;
     consider Y being Subset of X such that
   A45: t = "/\"({uparrow x : ex z st x = {z} & z in Y}, IP) and
   A46: Y in FF by A43;
     set Xsi = {uparrow x : ex z st x = {z} & z in Y};
          Xsi c= cIP proof let r be set; assume r in Xsi;
          then consider xz being Element of BP such that
        A47: r = uparrow xz and
               ex z being Element of X st xz = {z} & z in Y;
         thus r in cIP by A2,A3,A47;
        end;
     then reconsider Xsi as Subset of IP;
   A48: h preserves_inf_of Xsi by A7,WAYBEL_0:def 32;
         ex_inf_of Xsi, IP by YELLOW_0:17;
   then A49: inf (h.:Xsi) = h.inf Xsi by A48,WAYBEL_0:def 30;
     set Xsif = {f.(uparrow x) : ex z st x = {z} & z in Y};
         now let u be set;
        hereby assume u in h.:Xsi;
          then consider v being set such that
              v in the carrier of IP and
        A50: v in Xsi and
        A51: u = h.v by FUNCT_2:115;
          consider x such that
        A52: v = uparrow x and
        A53: ex z st x = {z} & z in Y by A50;
            consider z such that
        A54: x = {z} & z in Y by A53;
              v in FUF by A42,A52,A54;
            then h.v = f.v by A1,FUNCT_1:72;
         hence u in Xsif by A51,A52,A53;
        end;
       assume u in Xsif; then consider x such that
       A55: u = f.(uparrow x) and
       A56: ex z st x = {z} & z in Y;
           consider z such that
       A57: x = {z} & z in Y by A56;
       A58: uparrow x in Xsi by A56;
             uparrow x in FUF by A42,A57;
           then h.(uparrow x) = f.(uparrow x) by A1,FUNCT_1:72;
       hence u in h.:Xsi by A55,A58,FUNCT_2:43;
       end;
      then h.:Xsi = Xsif by TARSKI:2;
    hence s in Xsf by A44,A45,A46,A49;
   end;
   assume s in Xsf; then consider Y being Subset of X such that
   A59: s = "/\"({f.(uparrow x) : ex z st x = {z} & z in Y}, L) and
   A60: Y in FF;
     set Xsi = {uparrow x : ex z st x = {z} & z in Y};
          Xsi c= cIP proof let r be set; assume r in Xsi;
          then consider xz being Element of BP such that
        A61: r = uparrow xz and
               ex z being Element of X st xz = {z} & z in Y;
         thus r in cIP by A2,A3,A61;
        end;
     then reconsider Xsi as Subset of IP;
   A62: h preserves_inf_of Xsi by A7,WAYBEL_0:def 32;
         ex_inf_of Xsi, IP by YELLOW_0:17;
   then A63: inf (h.:Xsi) = h.inf Xsi by A62,WAYBEL_0:def 30;
     set Xsif = {f.(uparrow x) : ex z st x = {z} & z in Y};
   A64: inf Xsi in Xs by A60;
         now let u be set;
        hereby assume u in h.:Xsi;
          then consider v being set such that
              v in the carrier of IP and
        A65: v in Xsi and
        A66: u = h.v by FUNCT_2:115;
          consider x such that
        A67: v = uparrow x and
        A68: ex z st x = {z} & z in Y by A65;
            consider z such that
        A69: x = {z} & z in Y by A68;
              v in FUF by A42,A67,A69;
            then h.v = f.v by A1,FUNCT_1:72;
         hence u in Xsif by A66,A67,A68;
        end;
       assume u in Xsif; then consider x such that
       A70: u = f.(uparrow x) and
       A71: ex z st x = {z} & z in Y;
           consider z such that
       A72: x = {z} & z in Y by A71;
       A73: uparrow x in Xsi by A71;
             uparrow x in FUF by A42,A72;
           then h.(uparrow x) = f.(uparrow x) by A1,FUNCT_1:72;
       hence u in h.:Xsi by A70,A73,FUNCT_2:43;
       end;
      then h.:Xsi = Xsif by TARSKI:2;
   hence s in h.:Xs by A59,A63,A64,FUNCT_2:43;
  end;
 then A74: h.:Xs = Xsf by TARSKI:2;
  thus h'.Fi
     = sup (h.:Xs) by A5,A6,A40,A41,WAYBEL_0:def 31
    .= F'.Fi by A5,A74,Def3;
 end;
 hence h = f-extension_to_hom by FUNCT_2:113;
end;

theorem Th16:
 FixedUltraFilters X is_FreeGen_set_of InclPoset Filt BoolePoset X
proof set FUF = FixedUltraFilters X;
 set IP = InclPoset Filt BoolePoset X;
 let L be continuous complete (non empty Poset);
 let f be Function of FUF, the carrier of L;
 reconsider F = f-extension_to_hom as CLHomomorphism of IP, L
  by WAYBEL16:def 1;
 take F;
 thus F|FUF = f by Th14;
 let h' be CLHomomorphism of IP, L;
 assume h'|FUF = f;
 hence h' = F by Th15;
end;

theorem Th17:
 for L, M being continuous complete LATTICE, F, G being set
  st F is_FreeGen_set_of L & G is_FreeGen_set_of M & Card F = Card G
   holds L, M are_isomorphic
proof let L, M be continuous complete LATTICE, Lg, Mg be set such that
A1: Lg is_FreeGen_set_of L and
A2: Mg is_FreeGen_set_of M and
A3: Card Lg = Card Mg;
     Lg,Mg are_equipotent by A3,CARD_1:21; then consider f being Function
   such that
A4: f is one-to-one and
A5: dom f = Lg and
A6: rng f = Mg by WELLORD2:def 4;
   set g = f";
A7: dom g = Mg by A4,A6,FUNCT_1:55;
A8: rng g = Lg by A4,A5,FUNCT_1:55;
    reconsider Lg as Subset of L by A1,Th7;
    reconsider Mg as Subset of M by A2,Th7;
      Mg c= the carrier of M;
    then reconsider f as Function of Lg, the carrier of M
      by A5,A6,FUNCT_2:def 1,RELSET_1:11;
      Lg c= the carrier of L;
    then reconsider g as Function of Mg, the carrier of L
      by A7,A8,FUNCT_2:def 1,RELSET_1:11;
    consider F being CLHomomorphism of L, M such that
A9: F|Lg = f and
      for h' being CLHomomorphism of L, M st h'|Lg = f holds h' = F by A1,Def1;
    consider G being CLHomomorphism of M, L such that
A10: G|Mg = g and
      for h' being CLHomomorphism of M, L st h'|Mg = g holds h' = G by A2,Def1;
    reconsider GF = G*F as CLHomomorphism of L, L by Th2;
      GF|Lg = G*f by A9,RELAT_1:112
         .= g*f by A6,A10,FUNCT_4:2
         .= id Lg by A4,A5,FUNCT_1:61;
    then GF = id L by A1,Th8;
then A11: G*F = id the carrier of L by GRCAT_1:def 11;
then A12: F is one-to-one by FUNCT_2:29;
      F is directed-sups-preserving by WAYBEL16:def 1;
then A13: F is monotone by WAYBEL17:3;
    reconsider FG = F*G as CLHomomorphism of M, M by Th2;
      FG|Mg = F*g by A10,RELAT_1:112
         .= f*g by A8,A9,FUNCT_4:2
         .= id Mg by A4,A6,FUNCT_1:61;
    then FG = id M by A2,Th8;
    then F*G = id the carrier of M by GRCAT_1:def 11;
    then rng F = the carrier of M by FUNCT_2:29;
then A14: G = (F qua Function)" by A11,A12,FUNCT_2:36;
      G is directed-sups-preserving by WAYBEL16:def 1;
 then G is monotone by WAYBEL17:3;
   then F is isomorphic by A12,A13,A14,WAYBEL_0:def 38;
 hence L, M are_isomorphic by WAYBEL_1:def 8;
end;

theorem :: Theorem 4.17, p. 90-91
   for L being continuous complete LATTICE, G being set
  st G is_FreeGen_set_of L & Card G = Card X
   holds L, InclPoset Filt BoolePoset X are_isomorphic
proof let L be continuous complete LATTICE, G be set such that
A1: G is_FreeGen_set_of L and
A2: Card G = Card X;
A3: FixedUltraFilters X is_FreeGen_set_of InclPoset Filt BoolePoset X by Th16;
     Card X = Card FixedUltraFilters X by Th10;
 hence L, InclPoset Filt BoolePoset X are_isomorphic by A1,A2,A3,Th17;
end;

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