The Mizar article:

Continuous Lattices of Maps between T$_0$ Spaces

by
Grzegorz Bancerek

Received September 24, 1999

Copyright (c) 1999 Association of Mizar Users

MML identifier: WAYBEL26
[ MML identifier index ]


environ

 vocabulary YELLOW_1, PBOOLE, CARD_3, WAYBEL_3, MONOID_0, FUNCT_1, WAYBEL18,
      PRE_TOPC, ORDERS_1, WAYBEL24, WAYBEL25, RELAT_2, TSP_1, ORDINAL2, CAT_1,
      YELLOW_0, GROUP_1, BOOLE, YELLOW_9, WAYBEL11, FUNCT_3, RELAT_1, WELLORD1,
      SEQ_1, T_0TOPSP, WAYBEL_0, SEQM_3, BINOP_1, QUANTAL1, FUNCOP_1, SUBSET_1,
      BORSUK_1, GROUP_6, YELLOW16, TOPS_2, BHSP_3, REALSET1, URYSOHN1,
      LATTICE3, LATTICES, FUNCTOR0, WAYBEL_1, PRALG_2, RLVECT_2, FUNCT_2,
      PROB_1, CANTOR_1, FUNCT_4, WAYBEL_9, MCART_1, FINSET_1, FUNCT_5,
      SETFAM_1, TARSKI, WAYBEL26;
 notation TARSKI, XBOOLE_0, ENUMSET1, ZFMISC_1, SUBSET_1, MCART_1, FINSET_1,
      RELAT_1, FUNCT_1, RELSET_1, TOPS_2, FUNCT_3, FUNCT_4, FUNCT_5, STRUCT_0,
      REALSET1, PROB_1, CARD_3, ZF_FUND1, PBOOLE, MONOID_0, PRALG_1, PRALG_2,
      PRALG_3, PRE_CIRC, FUNCT_7, WELLORD1, ORDERS_1, LATTICE3, FUNCT_2,
      GRCAT_1, PRE_TOPC, TSP_1, CANTOR_1, URYSOHN1, T_0TOPSP, BORSUK_1,
      QUANTAL1, YELLOW_0, WAYBEL_0, YELLOW_1, YELLOW_2, WAYBEL_1, YELLOW_9,
      WAYBEL_3, WAYBEL_9, WAYBEL11, WAYBEL18, WAYBEL24, WAYBEL25, YELLOW16;
 constructors ENUMSET1, SEQM_3, ORDERS_3, WAYBEL_5, WAYBEL_1, WAYBEL17,
      ZF_FUND1, QUANTAL1, GRCAT_1, CANTOR_1, TOPS_2, TSP_1, TDLAT_3, YELLOW_9,
      URYSOHN1, NATTRA_1, TOLER_1, PRALG_3, FUNCT_7, WAYBEL18, WAYBEL24,
      WAYBEL25, YELLOW16, MONOID_0, PROB_1;
 clusters STRUCT_0, WAYBEL_0, WAYBEL_3, RELSET_1, YELLOW_1, LATTICE3, BORSUK_2,
      WAYBEL10, WAYBEL17, YELLOW_9, YELLOW_0, FUNCT_1, SUBSET_1, MONOID_0,
      PRE_TOPC, TOPS_1, TSP_1, YELLOW_2, YELLOW_6, WAYBEL_2, YELLOW14,
      WAYBEL18, WAYBEL24, WAYBEL25, FINSET_1, YELLOW16, XBOOLE_0;
 requirements SUBSET, BOOLE;
 definitions TARSKI, RELAT_1, MONOID_0, YELLOW_0, BORSUK_1, WAYBEL_0, WAYBEL_1,
      T_0TOPSP, YELLOW16, URYSOHN1, XBOOLE_0;
 theorems YELLOW_0, WAYBEL_0, YELLOW_1, YELLOW_2, WAYBEL_1, PRE_TOPC, BORSUK_1,
      TOPMETR, ORDERS_1, YELLOW12, WAYBEL10, WAYBEL24, WAYBEL25, RELAT_1,
      FUNCT_2, FUNCT_1, TOPS_2, TOPS_3, ENUMSET1, FUNCT_3, WAYBEL_3, PBOOLE,
      FUNCOP_1, CARD_3, TARSKI, ZFMISC_1, RELSET_1, WELLORD1, TSP_1, TOPS_1,
      WAYBEL21, GRCAT_1, QUANTAL1, CANTOR_1, FUNCT_7, YELLOW_9, WAYBEL18,
      WAYBEL20, MCART_1, YELLOW14, WAYBEL11, FINSET_1, WAYBEL15, REALSET1,
      PRALG_1, PRALG_2, YELLOW16, WAYBEL14, FUNCT_5, CARD_5, PRALG_3, SETFAM_1,
      XBOOLE_0, XBOOLE_1;
 schemes FUNCT_1, PRALG_2, COMPTS_1;

begin

definition
 let I be set;
 let J be RelStr-yielding ManySortedSet of I;
 redefine func product J; synonym I-POS_prod J;
end;

definition
 let I be set;
 let J be RelStr-yielding non-Empty ManySortedSet of I;
 cluster I-POS_prod J -> constituted-Functions;
 coherence
  proof let a be Element of I-POS_prod J;
   thus a is Function;
  end;
end;

definition
 let I be set;
 let J be TopSpace-yielding non-Empty ManySortedSet of I;
 redefine func product J; synonym I-TOP_prod J;
end;

:: 4.1. DEFINITION (a)
definition
 let X,Y be non empty TopSpace;
 func oContMaps(X, Y) -> non empty strict RelStr equals:
Def1:
  ContMaps(X, Omega Y);
 coherence;
end;

definition
 let X,Y be non empty TopSpace;
 cluster oContMaps(X, Y) -> reflexive transitive constituted-Functions;
 coherence
  proof oContMaps(X, Y) = ContMaps(X, Omega Y) by Def1;
   hence thesis;
  end;
end;

definition
 let X be non empty TopSpace;
 let Y be non empty T_0 TopSpace;
 cluster oContMaps(X, Y) -> antisymmetric;
 coherence
  proof oContMaps(X, Y) = ContMaps(X, Omega Y) by Def1;
   hence thesis;
  end;
end;

theorem Th1:
 for X,Y being non empty TopSpace
 for a being set holds
   a is Element of oContMaps(X, Y) iff a is continuous map of X, Omega Y
  proof let X,Y be non empty TopSpace;
   let a be set;
A1:  oContMaps(X, Y) = ContMaps(X, Omega Y) by Def1;
    hereby assume a is Element of oContMaps(X,Y);
      then a in the carrier of ContMaps(X, Omega Y) by A1;
      then ex f being map of X, Omega Y st a = f & f is continuous
       by WAYBEL24:def 3;
     hence a is continuous map of X, Omega Y;
    end;
   assume a is continuous map of X, Omega Y;
    then a in the carrier of ContMaps(X, Omega Y) by WAYBEL24:def 3;
   hence thesis by A1;
  end;

theorem Th2:
 for X,Y being non empty TopSpace
 for a being set holds
   a is Element of oContMaps(X, Y) iff a is continuous map of X, Y
  proof let X,Y be non empty TopSpace;
   let a be set;
A1:  the TopStruct of Omega Y = the TopStruct of Y by WAYBEL25:def 2;
A2:  the TopStruct of X = the TopStruct of X;
    hereby assume a is Element of oContMaps(X,Y);
then a is continuous map of X, Omega Y by Th1;
     hence a is continuous map of X, Y by A1,A2,YELLOW12:36;
    end;
   assume
   a is continuous map of X, Y;
    then a is continuous map of X, Omega Y by A1,A2,YELLOW12:36
;
   hence thesis by Th1;
  end;

theorem Th3:  :: see yellow14:9
 for X,Y being non empty TopSpace
 for a,b being Element of oContMaps(X,Y)
 for f,g being map of X, Omega Y
  st a = f & b = g holds a <= b iff f <= g
  proof let X,Y be non empty TopSpace;
   let a,b be Element of oContMaps(X,Y);
   let f,g be map of X, Omega Y such that
A1:  a = f & b = g;
      oContMaps(X,Y) = ContMaps(X, Omega Y) by Def1;
then A2:  oContMaps(X,Y) is full SubRelStr of (Omega Y)|^the carrier of X
     by WAYBEL24:def 3;
   then reconsider x = a, y = b as Element of (Omega Y)|^the carrier of X
     by YELLOW_0:59;
   a <= b iff x <= y by A2,YELLOW_0:60,61;
   hence thesis by A1,WAYBEL10:12;
  end;

definition
 let X,Y be non empty TopSpace;
 let x be Point of X;
 let A be Subset of oContMaps(X,Y);
 redefine func pi(A,x) -> Subset of Omega Y;
 coherence
  proof set XY = oContMaps(X, Y);
      XY = ContMaps(X, Omega Y) by Def1;
    then XY is SubRelStr of (Omega Y)|^the carrier of X by WAYBEL24:def 3;
    then the carrier of XY c= the carrier of (Omega Y)|^the carrier of X
     by YELLOW_0:def 13;
    then A c= the carrier of (Omega Y)|^the carrier of X by XBOOLE_1:1;
   then reconsider A as Subset of (Omega Y)|^the carrier of X;
      pi(A,x) is Subset of Omega Y;
   hence thesis;
  end;
end;

definition
 let X,Y be non empty TopSpace;
 let x be set;
 let A be non empty Subset of oContMaps(X,Y);
 cluster pi(A,x) -> non empty;
 coherence
  proof set XY = oContMaps(X, Y);
      XY = ContMaps(X, Omega Y) by Def1;
    then XY is SubRelStr of (Omega Y)|^the carrier of X by WAYBEL24:def 3;
    then the carrier of XY c= the carrier of (Omega Y)|^the carrier of X
     by YELLOW_0:def 13;
    then A c= the carrier of (Omega Y)|^the carrier of X by XBOOLE_1:1;
   then reconsider A as non empty Subset of (Omega Y)|^the carrier of X
    ;
      pi(A,x) <> {};
   hence thesis;
  end;
end;

theorem Th4:
 Omega Sierpinski_Space is TopAugmentation of BoolePoset 1
  proof
      BoolePoset 1 = InclPoset bool 1 by YELLOW_1:4;
then A1:  the carrier of BoolePoset 1 = {0,1} by YELLOW14:1,YELLOW_1:1;
A2:  the carrier of Sierpinski_Space = {0,1} by WAYBEL18:def 9;
   consider S being strict Scott TopAugmentation of BoolePoset 1;
      the topology of S = the topology of Sierpinski_Space &
    the RelStr of S = BoolePoset 1 by WAYBEL18:13,YELLOW_9:def 4;
    then Omega Sierpinski_Space = Omega S by A1,A2,WAYBEL25:13 .= S by WAYBEL25
:15;
   hence thesis;
  end;

theorem Th5:
 for X being non empty TopSpace
 ex f being map of InclPoset the topology of X, oContMaps(X, Sierpinski_Space)
  st f is isomorphic &
     for V being open Subset of X holds f.V = chi(V, the carrier of X)
  proof let X be non empty TopSpace;
   deffunc F(set) = chi($1, the carrier of X);
   consider f being Function such that
A1:  dom f = the topology of X and
A2:  for a being set st a in the topology of X holds f.a = F(a) from Lambda;
A3:  the carrier of InclPoset the topology of X = the topology of X
     by YELLOW_1:1;
      rng f c= the carrier of oContMaps(X, Sierpinski_Space)
     proof let x be set; assume x in rng f;
      then consider a being set such that
A4:     a in dom f & x = f.a by FUNCT_1:def 5;
      reconsider a as Subset of X by A1,A4;
         a is open by A1,A4,PRE_TOPC:def 5;
       then chi(a, the carrier of X) is continuous map of X, Sierpinski_Space
        by YELLOW16:48;
       then x is continuous map of X, Sierpinski_Space by A1,A2,A4;
       then x is Element of oContMaps(X, Sierpinski_Space) by Th2;
      hence thesis;
     end;
    then f is Function of the topology of X, the carrier of
           oContMaps(X, Sierpinski_Space) by A1,FUNCT_2:4;
   then reconsider f as map of InclPoset the topology of X,
           oContMaps(X, Sierpinski_Space) by A3;
   take f;
   set S = InclPoset the topology of X;
   set T = oContMaps(X, Sierpinski_Space);
A5:  f is one-to-one
     proof let x,y be Element of S;
         x in the topology of X & y in the topology of X by A3;
      then reconsider V = x, W = y as Subset of X;
         f.x = chi(V, the carrier of X) & f.y = chi(W, the carrier of X)
        by A2,A3;
      hence thesis by FUNCT_3:47;
     end;
A6:  rng f = the carrier of T
     proof thus rng f c= the carrier of T;
      let t be set; assume t in the carrier of T;
       then t is Element of T;
      then reconsider g = t as continuous map of X, Sierpinski_Space by Th2;
         the topology of Sierpinski_Space = {{}, {1}, {0,1}}
        by WAYBEL18:def 9;
       then {1} in the topology of Sierpinski_Space by ENUMSET1:14;
      then reconsider V = {1} as open Subset of Sierpinski_Space
        by PRE_TOPC:def 5;
       A7: g"V is open by TOPS_2:55;
then A8:     g"V in the topology of X by PRE_TOPC:def 5;
then A9:     f.(g"V) = chi(g"V, the carrier of X) by A2;
      reconsider c = chi(g"V, the carrier of X) as map of X, Sierpinski_Space
        by A7,YELLOW16:48;
         now let x be Element of X;
         the carrier of Sierpinski_Space = {0,1} by WAYBEL18:def 9;
then A10:       g.x = 0 or g.x = 1 by TARSKI:def 2;
           x in g"V or not x in g"V;
         then g.x in V & c.x = 1 or not g.x in V & c.x = 0
          by FUNCT_2:46,FUNCT_3:def 3;
        hence g.x = c.x by A10,TARSKI:def 1;
       end;
       then g = c by YELLOW_2:9;
      hence thesis by A1,A8,A9,FUNCT_1:def 5;
     end;
      now let x,y be Element of S;
     x in the topology of X & y in the topology of X by A3;
     then reconsider V = x, W = y as open Subset of X
       by PRE_TOPC:def 5;
     set cx = chi(V, the carrier of X), cy = chi(W, the carrier of X);
A11:    f.x = cx & f.y = cy by A2,A3;
        cx is continuous map of X, Sierpinski_Space &
      cy is continuous map of X, Sierpinski_Space by YELLOW16:48;
      then cx is Element of oContMaps(X,Sierpinski_Space) &
      cy is Element of oContMaps(X,Sierpinski_Space) by Th2;
     then reconsider cx, cy as continuous map of X, Omega Sierpinski_Space by
Th1;
        x <= y iff V c= W by YELLOW_1:3;
      then x <= y iff cx <= cy by Th4,YELLOW16:51;
     hence x <= y iff f.x <= f.y by A11,Th3;
    end;
   hence f is isomorphic by A5,A6,WAYBEL_0:66;
   let V be open Subset of X;
      V in the topology of X by PRE_TOPC:def 5;
   hence thesis by A2;
  end;

theorem Th6:
 for X being non empty TopSpace holds
   InclPoset the topology of X, oContMaps(X, Sierpinski_Space) are_isomorphic
  proof let X be non empty TopSpace;
   consider f being map of InclPoset the topology of X,
      oContMaps(X, Sierpinski_Space) such that
A1:  f is isomorphic and
      for V being open Subset of X holds f.V = chi(V, the carrier of X)
     by Th5;
   take f; thus thesis by A1;
  end;

:: 4.1. DEFINITION (b)
definition
 let X,Y,Z be non empty TopSpace;
 let f be continuous map of Y,Z;
 func oContMaps(X, f) -> map of oContMaps(X, Y), oContMaps(X, Z) means:
Def2:
  for g being continuous map of X,Y holds it.g = f*g;
 uniqueness
  proof let G1,G2 be map of oContMaps(X, Y), oContMaps(X, Z) such that
A1: for g being continuous map of X,Y holds G1.g = f*g and
A2: for g being continuous map of X,Y holds G2.g = f*g;
      now thus the carrier of oContMaps(X, Z) <> {};
     let x be Element of oContMaps(X, Y);
     reconsider g = x as continuous map of X, Y by Th2;
     thus G1.x = f*g by A1 .= G2.x by A2;
    end;
   hence thesis by FUNCT_2:113;
  end;
 existence
  proof
    deffunc F(set) = $1(#)f;
    consider F being Function such that
A3:  dom F = the carrier of oContMaps(X, Y) and
A4:  for x being set st x in the carrier of oContMaps(X, Y) holds F.x = F(x)
      from Lambda;
      rng F c= the carrier of oContMaps(X, Z)
     proof let y be set; assume y in rng F;
      then consider x being set such that
A5:     x in dom F & y = F.x by FUNCT_1:def 5;
         x is Element of oContMaps(X,Y) by A3,A5;
      then reconsider g = x as continuous map of X,Y by Th2;
         y = g(#)f by A3,A4,A5 .= f*g by YELLOW16:1;
       then y is Element of oContMaps(X,Z) by Th2;
      hence thesis;
     end;
    then F is Function of the carrier of oContMaps(X, Y),
      the carrier of oContMaps(X, Z) by A3,FUNCT_2:4;
   then reconsider F as map of oContMaps(X, Y), oContMaps(X, Z);
   take F; let g be continuous map of X,Y;
      g is Element of oContMaps(X,Y) by Th2;
   hence F.g = g(#)f by A4 .= f*g by YELLOW16:1;
  end;
 func oContMaps(f, X) -> map of oContMaps(Z, X), oContMaps(Y, X) means:
Def3:
  for g being continuous map of Z, X holds it.g = g*f;
 uniqueness
  proof let G1,G2 be map of oContMaps(Z, X), oContMaps(Y, X) such that
A6: for g being continuous map of Z,X holds G1.g = g*f and
A7: for g being continuous map of Z,X holds G2.g = g*f;
      now thus the carrier of oContMaps(Y, X) <> {};
     let x be Element of oContMaps(Z, X);
     reconsider g = x as continuous map of Z, X by Th2;
     thus G1.x = g*f by A6 .= G2.x by A7;
    end;
   hence thesis by FUNCT_2:113;
  end;
 existence
  proof
    deffunc F(set) = f(#)$1;
    consider F being Function such that
A8:  dom F = the carrier of oContMaps(Z, X) and
A9:  for x being set st x in the carrier of oContMaps(Z, X)
     holds F.x = F(x) from Lambda;
      rng F c= the carrier of oContMaps(Y, X)
     proof let y be set; assume y in rng F;
      then consider x being set such that
A10:     x in dom F & y = F.x by FUNCT_1:def 5;
         x is Element of oContMaps(Z,X) by A8,A10;
      then reconsider g = x as continuous map of Z,X by Th2;
         y = f(#)g by A8,A9,A10 .= g*f by YELLOW16:1;
       then y is Element of oContMaps(Y,X) by Th2;
      hence thesis;
     end;
    then F is Function of the carrier of oContMaps(Z, X),
      the carrier of oContMaps(Y, X) by A8,FUNCT_2:4;
   then reconsider F as map of oContMaps(Z, X), oContMaps(Y, X);
   take F; let g be continuous map of Z,X;
      g is Element of oContMaps(Z,X) by Th2;
   hence F.g = f(#)g by A9 .= g*f by YELLOW16:1;
  end;
end;


:: 4.2.  LEMMA (i)
theorem Th7:
 for X being non empty TopSpace
 for Y being monotone-convergence T_0-TopSpace
  holds oContMaps(X,Y) is directed-sups-inheriting
     SubRelStr of (Omega Y)|^the carrier of X
  proof let X be non empty TopSpace;
   let Y be monotone-convergence T_0-TopSpace;
      ContMaps(X,Omega Y) is directed-sups-inheriting
     SubRelStr of (Omega Y) |^ the carrier of X by WAYBEL25:43;
   hence thesis by Def1;
  end;

theorem Th8:
 for X being non empty TopSpace
 for Y being monotone-convergence T_0-TopSpace
  holds oContMaps(X, Y) is up-complete
  proof let X be non empty TopSpace;
   let Y be monotone-convergence T_0-TopSpace;
A1:  ContMaps(X, Omega Y) is directed-sups-inheriting
     full SubRelStr of (Omega Y) |^ the carrier of X
      by WAYBEL24:def 3,WAYBEL25:43;
    oContMaps(X, Y) = ContMaps(X, Omega Y) by Def1;
   hence thesis by A1,YELLOW16:5;
  end;

theorem Th9:
 for X,Y,Z being non empty TopSpace
 for f being continuous map of Y,Z
  holds oContMaps(X, f) is monotone
  proof let X,Y,Z be non empty TopSpace;
   let f be continuous map of Y,Z;
  the TopStruct of Y = the TopStruct of Omega Y &
    the TopStruct of Z = the TopStruct of Omega Z by WAYBEL25:def 2;
   then reconsider f' = f as continuous map of Omega Y, Omega Z by YELLOW12:36;
   set Xf = oContMaps(X, f);
   let a,b be Element of oContMaps(X, Y);
   reconsider g1 = a, g2 = b as continuous map of X, Omega Y by Th1;
   assume a <= b;
then A1: g1 <= g2 by Th3;
      g1 is continuous map of X,Y & g2 is continuous map of X,Y by Th2;
then A2: Xf.a = f'*g1 & Xf.b = f'*g2 by Def2;
   reconsider fg1 = f'*g1, fg2 = f'*g2 as map of X, Omega Z;
      now let x be set; assume x in the carrier of X;
     then reconsider x' = x as Element of X;
        ex a, b being Element of Omega Y
       st a = g1.x' & b = g2.x' & a <= b by A1,YELLOW_2:def 1;
      then (f'*g1).x' = f'.(g1.x') & (f'*g2).x' = f'.(g2.x') & g1.x' <= g2.x'
       by FUNCT_2:21;
      then (f'*g1).x' <= (f'*g2).x' by WAYBEL_1:def 2;
     hence ex a,b being Element of Omega Z
       st a = (f'*g1).x & b = (f'*g2).x & a <= b;
    end;
    then fg1 <= fg2 by YELLOW_2:def 1;
   hence Xf.a <= Xf.b by A2,Th3;
  end;

theorem
   for X,Y being non empty TopSpace
 for f being continuous map of Y,Y st f is idempotent
  holds oContMaps(X, f) is idempotent
  proof let X,Y be non empty TopSpace;
   let f be continuous map of Y,Y such that
A1: f is idempotent;
   set Xf = oContMaps(X, f);
      now let g be Element of oContMaps(X, Y);
     reconsider h = g as continuous map of X,Y by Th2;
     thus (Xf*Xf).g = Xf.(Xf.g) by FUNCT_2:21 .= Xf.(f*h) by Def2
       .= f*(f*h) by Def2 .= (f*f)*h by RELAT_1:55
       .= f*h by A1,QUANTAL1:def 9 .= Xf.g by Def2;
    end;
    then Xf*Xf = Xf by YELLOW_2:9;
   hence thesis by QUANTAL1:def 9;
  end;

theorem Th11:
 for X,Y,Z being non empty TopSpace
 for f being continuous map of Y,Z
  holds oContMaps(f, X) is monotone
  proof let X,Y,Z be non empty TopSpace;
   let f be continuous map of Y,Z;
  the TopStruct of Y = the TopStruct of Omega Y &
    the TopStruct of Z = the TopStruct of Omega Z by WAYBEL25:def 2;
   then reconsider f' = f as continuous map of Omega Y, Omega Z by YELLOW12:36;
   set Xf = oContMaps(f, X);
   let a,b be Element of oContMaps(Z, X);
   reconsider g1 = a, g2 = b as continuous map of Z, Omega X by Th1;
   assume a <= b;
then A1: g1 <= g2 by Th3;
      g1 is continuous map of Z,X & g2 is continuous map of Z,X by Th2;
then A2: Xf.a = g1*f' & Xf.b = g2*f' by Def3;
   then reconsider fg1 = g1*f', fg2 = g2*f' as map of Y, Omega X by Th1;
      now let x be set; assume x in the carrier of Y;
     then reconsider x' = x as Element of Y;
        (g1*f).x' = g1.(f.x') & (g2*f).x' = g2.(f.x') by FUNCT_2:21;
     hence ex a, b being Element of Omega X
       st a = (g1*f).x & b = (g2*f).x & a <= b by A1,YELLOW_2:def 1;
    end;
    then fg1 <= fg2 by YELLOW_2:def 1;
   hence Xf.a <= Xf.b by A2,Th3;
  end;

theorem Th12:
 for X,Y being non empty TopSpace
 for f being continuous map of Y,Y st f is idempotent
  holds oContMaps(f, X) is idempotent
  proof let X,Y be non empty TopSpace;
   let f be continuous map of Y,Y such that
A1: f is idempotent;
   set fX = oContMaps(f, X);
      now let g be Element of oContMaps(Y, X);
     reconsider h = g as continuous map of Y,X by Th2;
     thus (fX*fX).g = fX.(fX.g) by FUNCT_2:21 .= fX.(h*f) by Def3
       .= h*f*f by Def3 .= h*(f*f) by RELAT_1:55
       .= h*f by A1,QUANTAL1:def 9 .= fX.g by Def3;
    end;
    then fX*fX = fX by YELLOW_2:9;
   hence thesis by QUANTAL1:def 9;
  end;

theorem Th13:
 for X,Y,Z being non empty TopSpace
 for f being continuous map of Y,Z
 for x being Element of X, A being Subset of oContMaps(X, Y)
   holds pi(oContMaps(X,f).:A, x) = f.:pi(A, x)
  proof let X,Y,Z be non empty TopSpace;
   let f be continuous map of Y,Z;
   set Xf = oContMaps(X,f);
   let x be Element of X, A be Subset of oContMaps(X, Y);
   thus pi(Xf.:A,x) c= f.:pi(A,x)
     proof let a be set; assume a in pi(Xf.:A,x);
      then consider h being Function such that
A1:    h in Xf.:A & a = h.x by CARD_3:def 6;
      consider g being set such that
A2:    g in the carrier of oContMaps(X,Y) & g in A & h = Xf.g
        by A1,FUNCT_2:115;
         g is Element of oContMaps(X,Y) by A2;
      then reconsider g as continuous map of X,Y by Th2;
         h = f*g by A2,Def2;
       then a = f.(g.x) & g.x in pi(A,x) & the carrier of Z <> {}
        by A1,A2,CARD_3:def 6,FUNCT_2:21;
      hence thesis by FUNCT_2:43;
     end;
   let a be set; assume a in f.:pi(A,x);
   then consider b being set such that
A3: b in the carrier of Y & b in pi(A,x) & a = f.b by FUNCT_2:115;
   consider g being Function such that
A4: g in A & b = g.x by A3,CARD_3:def 6;
      g is Element of oContMaps(X,Y) by A4;
   then reconsider g as continuous map of X,Y by Th2;
A5: a = (f*g).x by A3,A4,FUNCT_2:21;
      f*g = Xf.g & the carrier of oContMaps(X,Z) <> {} by Def2;
    then f*g in Xf.:A by A4,FUNCT_2:43;
   hence thesis by A5,CARD_3:def 6;
  end;

:: 4.2.  LEMMA (ii)
theorem Th14:
 for X being non empty TopSpace
 for Y,Z being monotone-convergence T_0-TopSpace
 for f being continuous map of Y,Z
  holds oContMaps(X, f) is directed-sups-preserving
  proof let X be non empty TopSpace;
   let Y,Z be monotone-convergence T_0-TopSpace;
A1:  oContMaps(X, Z) is up-complete by Th8;
   let f be continuous map of Y,Z;
  the TopStruct of Y = the TopStruct of Omega Y &
    the TopStruct of Z = the TopStruct of Omega Z by WAYBEL25:def 2;
   then reconsider f' = f as continuous map of Omega Y, Omega Z by YELLOW12:36;
   let A be Subset of oContMaps(X, Y); assume A is non empty directed;
   then reconsider A' = A as non empty directed Subset of oContMaps(X, Y);
      oContMaps(X,Y) = ContMaps(X, Omega Y) by Def1;
   then reconsider XY = oContMaps(X, Y) as directed-sups-inheriting non empty
     full SubRelStr of (Omega Y) |^ the carrier of X by Th7,WAYBEL24:def 3;
   reconsider B = A' as non empty directed Subset of XY;
   reconsider B' = B as non empty directed Subset of
      (Omega Y) |^ the carrier of X by YELLOW_2:7;
A2: ex_sup_of B', (Omega Y) |^ the carrier of X by WAYBEL_0:75;
then A3: sup B' = sup A by WAYBEL_0:7;
   set Xf = oContMaps(X, f);
      Xf is monotone by Th9;
   then reconsider fA' = Xf.:A' as
       non empty directed Subset of oContMaps(X, Z) by YELLOW_2:17;
      oContMaps(X,Z) = ContMaps(X, Omega Z) by Def1;
   then reconsider XZ = oContMaps(X, Z) as directed-sups-inheriting non empty
     full SubRelStr of (Omega Z) |^ the carrier of X by Th7,WAYBEL24:def 3;
   reconsider fB = fA' as non empty directed Subset of XZ;
   reconsider fB' = fB as non empty directed Subset of
      (Omega Z) |^ the carrier of X by YELLOW_2:7;
      ex_sup_of fB', (Omega Z) |^ the carrier of X by WAYBEL_0:75;
then A4: sup fB' = sup (oContMaps(X, f).:A) by WAYBEL_0:7;
   assume ex_sup_of A, oContMaps(X, Y);
      fA' is directed;
   hence ex_sup_of oContMaps(X, f).:A, oContMaps(X, Z) by A1,WAYBEL_0:75;
   reconsider sfA = sup (Xf.:A), XfsA = Xf.sup A as map of X, Omega Z by Th1;
   set I = the carrier of X;
   set J1 = I --> Omega Y;
   set J2 = I --> Omega Z;
A5: (Omega Z) |^ I = I-POS_prod J2 by YELLOW_1:def 5;
   then reconsider fB'' = fB' as non empty directed Subset of I-POS_prod J2;
A6: (Omega Y) |^ the carrier of X = I-POS_prod J1 by YELLOW_1:def 5;
   then reconsider B'' = B' as non empty directed Subset of I-POS_prod J1;
   reconsider sA = sup A as continuous map of X,Y by Th2;
   now let x be Element of X;
        J2.x = Omega Z & pi(fB'',x) is directed by FUNCOP_1:13,YELLOW16:37;
     hence ex_sup_of pi(fB'',x), J2.x by WAYBEL_0:75;
    end;
then A7: ex_sup_of fB'', I-POS_prod J2 by YELLOW16:33;
      now let x be Element of X;
A8:   (sup B'').x = sup pi(B'',x) by A2,A6,YELLOW16:35;
A9:   J1.x = Omega Y & J2.x = Omega Z by FUNCOP_1:13;
     then reconsider Bx = pi(B'',x) as directed non empty Subset of Omega Y by
YELLOW16:37;
A10:   ex_sup_of Bx, Omega Y & f' preserves_sup_of Bx by WAYBEL_0:75,def 37;
A11:   pi(fB'',x) = f'.:Bx by Th13;
     thus sfA.x = sup pi(fB'',x) by A4,A5,A7,YELLOW16:35
       .= f.sup Bx by A9,A10,A11,WAYBEL_0:def 31
       .= (f*sA).x by A3,A6,A8,A9,FUNCT_2:21
       .= XfsA.x by Def2;
    end;
   hence sup (oContMaps(X, f).:A) = oContMaps(X, f).sup A by YELLOW_2:9;
  end;

theorem Th15:
 for X,Y,Z being non empty TopSpace
 for f being continuous map of Y,Z
 for x being Element of Y, A being Subset of oContMaps(Z, X)
   holds pi(oContMaps(f, X).:A, x) = pi(A, f.x)
  proof let X,Y,Z be non empty TopSpace;
   let f be continuous map of Y,Z;
   set fX = oContMaps(f, X);
   let x be Element of Y, A be Subset of oContMaps(Z, X);
   thus pi(fX.:A,x) c= pi(A,f.x)
     proof let a be set; assume a in pi(fX.:A,x);
      then consider h being Function such that
A1:    h in fX.:A & a = h.x by CARD_3:def 6;
      consider g being set such that
A2:    g in the carrier of oContMaps(Z,X) & g in A & h = fX.g
        by A1,FUNCT_2:115;
         g is Element of oContMaps(Z,X) by A2;
      then reconsider g as continuous map of Z,X by Th2;
         h = g*f by A2,Def3;
       then a = g.(f.x) by A1,FUNCT_2:21;
      hence thesis by A2,CARD_3:def 6;
     end;
   let a be set; assume a in pi(A,f.x);
   then consider g being Function such that
A3: g in A & a = g.(f.x) by CARD_3:def 6;
      g is Element of oContMaps(Z,X) by A3;
   then reconsider g as continuous map of Z,X by Th2;
A4: a = (g*f).x by A3,FUNCT_2:21;
      g*f = fX.g & the carrier of oContMaps(Y,X) <> {} by Def3;
    then g*f in fX.:A by A3,FUNCT_2:43;
   hence thesis by A4,CARD_3:def 6;
  end;

theorem Th16:
 for Y,Z being non empty TopSpace
 for X being monotone-convergence T_0-TopSpace
 for f being continuous map of Y,Z
  holds oContMaps(f, X) is directed-sups-preserving
  proof let Y,Z be non empty TopSpace;
   let X be monotone-convergence T_0-TopSpace;
A1:  oContMaps(Y, X) is up-complete by Th8;
   let f be continuous map of Y,Z;
   let A be Subset of oContMaps(Z, X); assume A is non empty directed;
   then reconsider A' = A as non empty directed Subset of oContMaps(Z, X);
      oContMaps(Z,X) = ContMaps(Z, Omega X) by Def1;
   then reconsider ZX = oContMaps(Z, X) as directed-sups-inheriting non empty
     full SubRelStr of (Omega X) |^ the carrier of Z by Th7,WAYBEL24:def 3;
   reconsider B = A' as non empty directed Subset of ZX;
   reconsider B' = B as non empty directed Subset of
      (Omega X) |^ the carrier of Z by YELLOW_2:7;
A2: ex_sup_of B', (Omega X) |^ the carrier of Z by WAYBEL_0:75;
then A3: sup B' = sup A by WAYBEL_0:7;
   set fX = oContMaps(f, X);
      fX is monotone by Th11;
   then reconsider fA' = fX.:A' as
       non empty directed Subset of oContMaps(Y, X) by YELLOW_2:17;
      oContMaps(Y,X) = ContMaps(Y, Omega X) by Def1;
   then reconsider YX = oContMaps(Y, X) as directed-sups-inheriting non empty
     full SubRelStr of (Omega X) |^ the carrier of Y by Th7,WAYBEL24:def 3;
   reconsider fB = fA' as non empty directed Subset of YX;
   reconsider fB' = fB as non empty directed Subset of
      (Omega X) |^ the carrier of Y by YELLOW_2:7;
      ex_sup_of fB', (Omega X) |^ the carrier of Y by WAYBEL_0:75;
then A4: sup fB' = sup (oContMaps(f, X).:A) by WAYBEL_0:7;
   assume ex_sup_of A, oContMaps(Z, X);
      fA' is directed;
   hence ex_sup_of oContMaps(f, X).:A, oContMaps(Y, X) by A1,WAYBEL_0:75;
   reconsider sfA = sup (fX.:A), XfsA = fX.sup A as map of Y, Omega X by Th1;
   set I1 = the carrier of Z, I2 = the carrier of Y;
   set J1 = I1 --> Omega X;
   set J2 = I2 --> Omega X;
A5: (Omega X) |^ I2 = I2-POS_prod J2 by YELLOW_1:def 5;
   then reconsider fB'' = fB' as non empty directed Subset of I2-POS_prod J2;
A6: (Omega X) |^ I1 = I1-POS_prod J1 by YELLOW_1:def 5;
   then reconsider B'' = B' as non empty directed Subset of I1-POS_prod J1;
   reconsider sA = sup A as continuous map of Z,X by Th2;
   now let x be Element of Y;
        J2.x = Omega X & pi(fB'',x) is directed by FUNCOP_1:13,YELLOW16:37;
     hence ex_sup_of pi(fB'',x), J2.x by WAYBEL_0:75;
    end;
then A7: ex_sup_of fB'', I2-POS_prod J2 by YELLOW16:33;
      now let x be Element of Y;
A8:   J1.(f.x) = Omega X & J2.x = Omega X by FUNCOP_1:13;
A9:   pi(fB'',x) = pi(B'',f.x) by Th15;
     thus sfA.x = sup pi(fB'',x) by A4,A5,A7,YELLOW16:35
       .= (sup B'').(f.x) by A2,A6,A8,A9,YELLOW16:35
       .= (sA*f).x by A3,A6,FUNCT_2:21
       .= XfsA.x by Def3;
    end;
   hence sup (oContMaps(f, X).:A) = oContMaps(f, X).sup A by YELLOW_2:9;
  end;

:: 4.3.  LEMMA (i) genralized
theorem Th17:
 for X,Z being non empty TopSpace
 for Y being non empty SubSpace of Z
  holds oContMaps(X, Y) is full SubRelStr of oContMaps(X, Z)
  proof let X,Z be non empty TopSpace, Y be non empty SubSpace of Z;
   set XY = oContMaps(X, Y), XZ = oContMaps(X, Z);
A1: [#]Y c= [#]Z by PRE_TOPC:def 9;
A2: [#]Y = the carrier of Y & [#]Z = the carrier of Z by PRE_TOPC:12;
A3: Omega Y is full SubRelStr of Omega Z by WAYBEL25:17;
      XY is SubRelStr of XZ
     proof
      thus
A4:     the carrier of XY c= the carrier of XZ
        proof let x be set; assume x in the carrier of XY;
          then x is Element of XY;
         then reconsider f = x as continuous map of X, Y by Th2;
A5:        dom f = the carrier of X & rng f c= the carrier of Y
           by FUNCT_2:def 1;
            rng f c= the carrier of Z by A1,A2,XBOOLE_1:1;
          then f is Function of the carrier of X, the carrier of Z
           by A5,FUNCT_2:4;
          then x is continuous map of X,Z by TOPMETR:7;
          then x is Element of XZ & XZ is non empty by Th2;
         hence thesis;
        end;
      let x,y be set; assume
A6:     [x,y] in the InternalRel of XY;
then A7:    x in the carrier of XY & y in the carrier of XY by ZFMISC_1:106;
      then reconsider x, y as Element of XY;
      reconsider a = x, b = y as Element of XZ by A4,A7;
      reconsider f = x, g = y as continuous map of X, Omega Y by Th1;
      reconsider f' = a, g' = b as continuous map of X, Omega Z by Th1;
         x <= y by A6,ORDERS_1:def 9;
       then f <= g by Th3;
       then f' <= g' by A3,YELLOW16:2;
       then a <= b by Th3;
      hence thesis by ORDERS_1:def 9;
     end;
   then reconsider XY as non empty SubRelStr of XZ;
A8:  (the InternalRel of XZ)|_2 the carrier of XY =
      (the InternalRel of XZ) /\ [:the carrier of XY, the carrier of XY:]
       by WELLORD1:def 6;
      the InternalRel of XY = ((the InternalRel of XZ)|_2 the carrier of XY)
      qua set
     proof
         the InternalRel of XY c= the InternalRel of XZ by YELLOW_0:def 13;
      hence the InternalRel of XY c= (the InternalRel of XZ)|_2
the carrier of XY
        by A8,XBOOLE_1:19;
      let x,y be set; assume
A9:     [x,y] in (the InternalRel of XZ)|_2 the carrier of XY;
       then [x,y] in
 [:the carrier of XY, the carrier of XY:] by A8,XBOOLE_0:def 3;
then A10:     x in the carrier of XY & y in the carrier of XY by ZFMISC_1:106;
      then reconsider x,y as Element of XY;
         the carrier of XY c= the carrier of XZ by YELLOW_0:def 13;
      then reconsider a = x, b = y as Element of XZ by A10;
      reconsider f = x, g = y as continuous map of X, Omega Y by Th1;
      reconsider f' = a, g' = b as continuous map of X, Omega Z by Th1;
         [a,b] in the InternalRel of XZ by A8,A9,XBOOLE_0:def 3;
       then a <= b by ORDERS_1:def 9;
       then f' <= g' by Th3;
       then f <= g by A3,YELLOW16:3;
       then x <= y by Th3;
      hence thesis by ORDERS_1:def 9;
     end;
   hence thesis by YELLOW_0:def 14;
  end;

theorem Th18:
 for Z being monotone-convergence T_0-TopSpace
 for Y being non empty SubSpace of Z
 for f being continuous map of Z,Y st f is_a_retraction
  holds Omega Y is directed-sups-inheriting SubRelStr of Omega Z
  proof
   let Z be monotone-convergence T_0-TopSpace;
   let Y be non empty SubSpace of Z;
   reconsider OZ = Omega Z as non empty up-complete (non empty Poset);
   reconsider OY = Omega Y as full non empty SubRelStr of Omega Z
     by WAYBEL25:17;
   let f be continuous map of Z,Y; assume
A1:  f is_a_retraction;
A2:  dom f = the carrier of Z & rng f c= the carrier of Y by FUNCT_2:def 1;
      [#]Y c= [#]Z & [#]Y = the carrier of Y & [#]Z = the carrier of Z
     by PRE_TOPC:12,def 9;
    then rng f c= the carrier of Z by XBOOLE_1:1;
    then f is Function of the carrier of Z, the carrier of Z
     by A2,FUNCT_2:def 1,RELSET_1:11;
then A3:  f is continuous map of Z,Z by TOPMETR:7;
   the TopStruct of Omega Z = the TopStruct of Z by WAYBEL25:def 2;
   then reconsider f' = f as continuous map of Omega Z, Omega Z
   by A3,YELLOW12:36;
   reconsider g = f' as map of OZ, OZ;
      g is idempotent directed-sups-preserving by A1,YELLOW16:47;
then A4:  Image g is directed-sups-inheriting by YELLOW16:6;
A5:  rng f = the carrier of Y by A1,YELLOW16:46;
A6:  the TopStruct of Omega Y = the TopStruct of Y &
    the TopStruct of Omega Z = the TopStruct of Z by WAYBEL25:def 2;
A7:  Image g = subrelstr rng g & rng g = the carrier of subrelstr rng g
     by YELLOW_0:def 15,YELLOW_2:def 2;
      the RelStr of OZ = the RelStr of Omega Z;
    then OY is directed-sups-inheriting by A4,A5,A6,A7,WAYBEL21:22;
   hence thesis;
  end;

Lm1:
 for Z being monotone-convergence T_0-TopSpace
 for Y being non empty SubSpace of Z
 for f being continuous map of Z,Y st f is_a_retraction
  holds Y is monotone-convergence
  proof
   let Z be monotone-convergence T_0-TopSpace;
   let Y be non empty SubSpace of Z;
   let f be continuous map of Z,Y; assume
      f is_a_retraction;
    then Y is_a_retract_of Z by BORSUK_1:def 20;
    then Y is_Retract_of Z by YELLOW16:58;
   hence thesis by WAYBEL25:36;
  end;

theorem Th19:
 for X being non empty TopSpace
 for Z being monotone-convergence T_0-TopSpace
 for Y being non empty SubSpace of Z
 for f being continuous map of Z,Y st f is_a_retraction
  holds
   oContMaps(X, f) is_a_retraction_of oContMaps(X, Z), oContMaps(X, Y)
  proof let X be non empty TopSpace;
   let Z be monotone-convergence T_0-TopSpace;
   let Y be non empty SubSpace of Z;
   set XY = oContMaps(X, Y), XZ = oContMaps(X, Z);
   reconsider uXZ = XZ as up-complete (non empty Poset) by Th8;
   reconsider sXY = XY as full non empty SubRelStr of uXZ by Th17;
   let f be continuous map of Z,Y; assume
A1:  f is_a_retraction;
   set F = oContMaps(X, f);
   reconsider Y' = Y as monotone-convergence T_0-TopSpace by A1,Lm1;
    oContMaps(X,Y') is up-complete by Th8;
   hence F is directed-sups-preserving map of XZ, XY by Th14;
      id XY = id the carrier of XY by GRCAT_1:def 11;
then A2:  dom id XY = the carrier of XY by RELAT_1:71;
A3:  the carrier of sXY c= the carrier of uXZ by YELLOW_0:def 13;
    then F|the carrier of XY is Function of the carrier of XY, the carrier of
XY
     by FUNCT_2:38;
then A4:  dom (F|the carrier of XY) = the carrier of XY by FUNCT_2:def 1;
      now let x be set; assume
A5:    x in the carrier of XY;
     then reconsider a = x as Element of XZ by A3;
     reconsider a as continuous map of X, Z by Th2;
        x is Element of XY by A5;
then A6:    rng f = the carrier of Y & x is map of X,Y by A1,Th2,YELLOW16:46;
    then f is idempotent & rng a c= the carrier of Y & dom f = the carrier of
Z
       by A1,FUNCT_2:def 1,RELSET_1:12,YELLOW16:47;
      then f*a = a by A6,YELLOW16:4;
     hence (id XY).x = f*a by A5,GRCAT_1:11
       .= F.a by Def2
       .= (F|the carrier of XY).x by A5,FUNCT_1:72;
    end;
   hence F|the carrier of XY = id XY by A2,A4,FUNCT_1:9;
      oContMaps(X,Y) = ContMaps(X, Omega Y) by Def1;
then A7:  oContMaps(X, Y') is directed-sups-inheriting full non empty
      SubRelStr of (Omega Y)|^the carrier of X by Th7,WAYBEL24:def 3;
      oContMaps(X,Z) = ContMaps(X, Omega Z) by Def1;
then A8:  oContMaps(X, Z) is directed-sups-inheriting full non empty
      SubRelStr of (Omega Z)|^the carrier of X by Th7,WAYBEL24:def 3;
      Omega Y is directed-sups-inheriting full SubRelStr of Omega Z
     by A1,Th18,WAYBEL25:17;
    then (Omega Y)|^the carrier of X is directed-sups-inheriting full
     SubRelStr of (Omega Z)|^the carrier of X by YELLOW16:41,44;
    then oContMaps(X,Y) is directed-sups-inheriting full
     SubRelStr of (Omega Z)|^the carrier of X by A7,YELLOW16:28,29;
   hence oContMaps(X, Y) is directed-sups-inheriting full
      SubRelStr of oContMaps(X, Z) by A8,Th17,YELLOW16:30;
  end;

theorem Th20:
 for X being non empty TopSpace
 for Z being monotone-convergence T_0-TopSpace
 for Y being non empty SubSpace of Z
  st Y is_a_retract_of Z
 holds oContMaps(X, Y) is_a_retract_of oContMaps(X, Z)
  proof let X be non empty TopSpace;
   let Z be monotone-convergence T_0-TopSpace;
   let Y be non empty SubSpace of Z;
   given f being continuous map of Z,Y such that
A1:  f is_a_retraction;
   take oContMaps(X, f);
   thus thesis by A1,Th19;
  end;

theorem Th21:
 for X,Y,Z being non empty TopSpace
 for f being continuous map of Y,Z st f is_homeomorphism
  holds oContMaps(X, f) is isomorphic
  proof let X,Y,Z be non empty TopSpace;
   let f be continuous map of Y,Z; assume
A1:  f is_homeomorphism;
   then reconsider g = f" as continuous map of Z,Y by TOPS_2:def 5;
A2: f is one-to-one & rng f = [#]Z & dom f = [#]Y by A1,TOPS_2:def 5;
   set Xf = oContMaps(X,f), Xg = oContMaps(X,g);
   set XY = oContMaps(X,Y), XZ = oContMaps(X,Z);
A3:  Xf is monotone & Xg is monotone by Th9;
      now let a be Element of XY;
     reconsider h = a as continuous map of X,Y by Th2;
     thus (Xg*Xf).a = Xg.(Xf.a) by FUNCT_2:21
       .= Xg.(f*h) by Def2
       .= g*(f*h) by Def2
       .= g*f*h by RELAT_1:55
       .= (id dom f)*h by A2,TOPS_2:65
       .= (id the carrier of Y)*h by A2,PRE_TOPC:12
       .= a by FUNCT_2:23
       .= (id XY).a by GRCAT_1:11;
    end;
then A4:  Xg*Xf = id XY by YELLOW_2:9;
      now let a be Element of XZ;
     reconsider h = a as continuous map of X,Z by Th2;
     thus (Xf*Xg).a = Xf.(Xg.a) by FUNCT_2:21
       .= Xf.(g*h) by Def2
       .= f*(g*h) by Def2
       .= f*g*h by RELAT_1:55
       .= (id rng f)*h by A2,TOPS_2:65
       .= (id the carrier of Z)*h by A2,PRE_TOPC:12
       .= a by FUNCT_2:23
       .= (id XZ).a by GRCAT_1:11;
    end;
    then Xf*Xg = id XZ by YELLOW_2:9;
   hence thesis by A3,A4,YELLOW16:17;
  end;

theorem Th22:
 for X,Y,Z being non empty TopSpace
  st Y,Z are_homeomorphic
  holds oContMaps(X, Y), oContMaps(X, Z) are_isomorphic
  proof let X,Y,Z be non empty TopSpace;
   given f being map of Y,Z such that
A1:  f is_homeomorphism;
   reconsider f as continuous map of Y,Z by A1,TOPS_2:def 5;
   take oContMaps(X, f); thus thesis by A1,Th21;
  end;

:: 4.3.  LEMMA (ii)
theorem Th23:
 for X being non empty TopSpace
 for Z being monotone-convergence T_0-TopSpace
 for Y being non empty SubSpace of Z
  st Y is_a_retract_of Z & oContMaps(X, Z) is complete continuous
 holds oContMaps(X, Y) is complete continuous
  proof let X be non empty TopSpace;
   let Z be monotone-convergence T_0-TopSpace;
   let Y be non empty SubSpace of Z;
   assume Y is_a_retract_of Z;
then A1:  oContMaps(X, Y) is_a_retract_of oContMaps(X,Z) by Th20;
   assume oContMaps(X, Z) is complete continuous;
    then oContMaps(X, Z) is complete continuous (non empty Poset);
   hence oContMaps(X, Y) is complete continuous by A1,YELLOW16:23,24;
  end;

theorem Th24:
 for X being non empty TopSpace
 for Y,Z being monotone-convergence T_0-TopSpace
  st Y is_Retract_of Z & oContMaps(X, Z) is complete continuous
 holds oContMaps(X, Y) is complete continuous
  proof let X be non empty TopSpace;
   let Y,Z be monotone-convergence T_0-TopSpace; assume
      Y is_Retract_of Z;
   then consider S being non empty SubSpace of Z such that
A1:  S is_a_retract_of Z & S,Y are_homeomorphic by YELLOW16:59;
A2:  oContMaps(X,S), oContMaps(X,Y) are_isomorphic by A1,Th22;
   assume oContMaps(X, Z) is complete continuous;
    then oContMaps(X,S) is complete continuous by A1,Th23;
   hence thesis by A2,WAYBEL15:11,WAYBEL20:18;
  end;

theorem Th25:
 for Y being non trivial T_0-TopSpace
  st not Y is_T1
 holds Sierpinski_Space is_Retract_of Y
  proof let Y be non trivial T_0-TopSpace;
   given p,q being Point of Y such that
A1:  p <> q and
A2:  for W,V being Subset of Y st W is open & V is open &
       p in W & not q in W & q in V holds p in V;
      (ex V being Subset of Y st V is open & p in V & not q in V) or
    (ex W being Subset of Y st W is open & not p in W & q in W)
     by A1,TSP_1:def 3;
   then consider V being Subset of Y such that
A3:  V is open and
A4:  p in V & not q in V or not p in V & q in V;
A5:  the TopStruct of Omega Y = the TopStruct of Y by WAYBEL25:def 2;
    then p is Element of Omega Y & q is Element of Omega Y;
   then consider x,y being Element of Omega Y such that
A6:  p in V & not q in V & x = q & y = p or
    not p in V & q in V & x = p & y = q by A4;
   reconsider V as open Subset of Omega Y by A3,A5,TOPS_3:76;
   reconsider c = chi(V, the carrier of Y) as
     continuous map of Y, Sierpinski_Space by A3,YELLOW16:48;
      now let W be open Subset of Omega Y;
        W is open Subset of Y by A5,TOPS_3:76;
     hence x in W implies y in W by A2,A3,A6;
    end;
    then (0,1) --> (x,y) is continuous map of Sierpinski_Space, Omega Y
      by YELLOW16:49;
   then reconsider i = (0,1) --> (x,y) as continuous map of Sierpinski_Space, Y
    by A5,YELLOW12:36;
      c*i = id Sierpinski_Space by A5,A6,YELLOW16:50;
   hence thesis by WAYBEL25:def 1;
  end;

theorem Th26:
 for X being non empty TopSpace
 for Y being non trivial T_0-TopSpace
  st oContMaps(X, Y) is with_suprema
  holds not Y is_T1
  proof let X be non empty TopSpace;
   let Y be non trivial T_0-TopSpace;
   consider a,b being Element of Y such that
A1:  a <> b by REALSET1:def 20;
   assume oContMaps(X, Y) is with_suprema;
   then reconsider XY = oContMaps(X, Y) as sup-Semilattice;
   reconsider f = X --> a, g = X --> b as continuous map of X, Y
      by BORSUK_1:36;
   reconsider ef = f, eg = g as Element of XY by Th2;
   reconsider h = ef "\/" eg, f = ef, g = eg as
      continuous map of X, Omega Y by Th1;
   consider i being Element of X;
      f = (the carrier of X) --> a & g = (the carrier of X) --> b
     by BORSUK_1:def 3;
then A2:  f.i = a & g.i = b by FUNCOP_1:13;
      now assume not ex x,y being Element of Omega Y st x <= y & x <> y;
then A3:    not (f.i <= h.i & f.i <> h.i) & not (g.i <= h.i & g.i <> h.i);
        ef <= ef "\/" eg & eg <= ef "\/" eg by YELLOW_0:22;
      then f <= h & g <= h by Th3;
      then (ex x,y being Element of Omega Y st x = f.i & y = h.i & x <= y) &
      (ex x,y being Element of Omega Y st x = g.i & y = h.i & x <= y)
       by YELLOW_2:def 1;
     hence contradiction by A1,A2,A3;
    end;
   then consider x,y being Element of Omega Y such that
A4:  x <= y & x <> y;
A5:  the TopStruct of Omega Y = the TopStruct of Y by WAYBEL25:def 2;
   then reconsider p = x, q = y as Element of Y;
   take p,q; thus p <> q by A4;
   let W,V be Subset of Y; assume
      W is open;
   then reconsider W as open Subset of Omega Y by A5,TOPS_3:76;
      W is upper;
   hence thesis by A4,WAYBEL_0:def 20;
  end;

definition
 cluster Sierpinski_Space -> non trivial monotone-convergence;
 coherence
  proof
A1:  the carrier of Sierpinski_Space = {0,1} by WAYBEL18:def 9;
      0 in {0,1} & 1 in {0,1} & 0 <> 1 by TARSKI:def 2;
   hence thesis by A1,REALSET1:def 20;
  end;
end;

definition
 cluster injective monotone-convergence non trivial T_0-TopSpace;
 existence
  proof take Sierpinski_Space; thus thesis;
  end;
end;

:: 4.4.  PROPOSITION
theorem Th27:
 for X being non empty TopSpace
 for Y being monotone-convergence non trivial T_0-TopSpace
  st oContMaps(X, Y) is complete continuous
 holds InclPoset the topology of X is continuous
  proof let X be non empty TopSpace;
   let Y be monotone-convergence non trivial T_0-TopSpace;
   assume
A1:  oContMaps(X, Y) is complete continuous;
    then oContMaps(X, Y) is complete continuous (non empty Poset);
    then not Y is_T1 by Th26;
    then Sierpinski_Space is_Retract_of Y by Th25;
then A2:  oContMaps(X, Sierpinski_Space) is complete continuous by A1,Th24;
      InclPoset the topology of X, oContMaps(X, Sierpinski_Space)
      are_isomorphic by Th6;
    then oContMaps(X, Sierpinski_Space), InclPoset the topology of X
      are_isomorphic by WAYBEL_1:7;
   hence thesis by A2,WAYBEL15:11;
  end;


theorem Th28:
 for X being non empty TopSpace, x being Point of X
 for Y being monotone-convergence T_0-TopSpace
 ex F being directed-sups-preserving projection
       map of oContMaps(X,Y), oContMaps(X,Y) st
 (for f being continuous map of X,Y holds F.f = X --> (f.x)) &
 ex h being continuous map of X,X st h = X --> x & F = oContMaps(h, Y)
  proof let X be non empty TopSpace, x be Point of X;
   let Y be monotone-convergence T_0-TopSpace;
   set XY = oContMaps(X,Y);
   reconsider f = X --> x as continuous map of X,X by BORSUK_1:36;
   set F = oContMaps(f, Y);
A1:  f = (the carrier of X) --> x by BORSUK_1:def 3;
      dom f = the carrier of X by FUNCT_2:def 1;
    then f*f = (the carrier of X) --> (f.x) by A1,FUNCOP_1:23
       .= f by A1,FUNCOP_1:13;
    then f is idempotent by QUANTAL1:def 9;
    then F is directed-sups-preserving idempotent map of XY,XY by Th12,Th16;
   then reconsider F as directed-sups-preserving projection map of XY,XY
    by WAYBEL_1:def 13;
   take F;
   hereby let h be continuous map of X,Y;
A2:   the carrier of X = dom h by FUNCT_2:def 1;
    thus F.h = h*(X --> x) by Def3
      .= h*((the carrier of X) --> x) by BORSUK_1:def 3
      .= (the carrier of X) --> (h.x) by A2,FUNCOP_1:23
      .= X --> (h.x) by BORSUK_1:def 3;
   end;
   thus thesis;
  end;

:: 4.5.  PROPOSITION
theorem Th29:
 for X being non empty TopSpace, Y being monotone-convergence T_0-TopSpace
  st oContMaps(X, Y) is complete continuous
 holds Omega Y is complete continuous
  proof let X be non empty TopSpace, Y be monotone-convergence T_0-TopSpace
   such that
A1:  oContMaps(X, Y) is complete continuous;
   consider b being Element of X;
   consider F being directed-sups-preserving projection map of oContMaps(X,Y),
     oContMaps(X,Y) such that
A2:  for f being continuous map of X,Y holds F.f = X --> (f.b) and
      ex h being continuous map of X,X st h = X --> b & F = oContMaps(h, Y)
     by Th28;
      oContMaps(X, Y) is complete continuous (non empty Poset) by A1;
then A3:  Image F is complete continuous LATTICE by WAYBEL15:17,YELLOW_2:37;
      oContMaps(X, Y) = ContMaps(X, Omega Y) by Def1;
    then oContMaps(X, Y) is full SubRelStr of (Omega Y)|^the carrier of X
     by WAYBEL24:def 3;
   then reconsider imF = Image F as full non empty SubRelStr of
     (Omega Y)|^the carrier of X by YELLOW16:28;
A4:  the carrier of imF = rng F by YELLOW_2:11;
A5:  dom F = the carrier of oContMaps(X,Y) by FUNCT_2:67;
A6:  the TopStruct of Omega Y = the TopStruct of Y by WAYBEL25:def 2;
      now let a be set;
     hereby assume a is Element of imF;
      then consider h being set such that
A7:     h in dom F & a = F.h by A4,FUNCT_1:def 5;
         h is Element of oContMaps(X,Y) by A7;
      then reconsider h as continuous map of X,Y by Th2;
      reconsider x = h.b as Element of Omega Y by A6;
         a = X --> (h.b) by A2,A7
        .= (the carrier of X) --> x by BORSUK_1:def 3;
      hence ex x being Element of Omega Y st a = (the carrier of X) --> x;
     end;
     given x being Element of Omega Y such that
A8:    a = (the carrier of X) --> x;
A9:    a = X --> x by A8,BORSUK_1:def 3;
      X --> x is continuous map of X, Omega Y by BORSUK_1:36;
then A10:    a is Element of oContMaps(X,Y) by A9,Th1;
     then reconsider h = a as continuous map of X,Y by Th2;
        h.b = x & X --> (h.b) = (the carrier of X) --> (h.b)
       by A8,BORSUK_1:def 3,FUNCOP_1:13;
      then F.a = X --> x by A2,A8,A9;
      then a in rng F by A5,A9,A10,FUNCT_1:def 5;
     hence a is Element of imF by A4;
    end;
    then Omega Y, imF are_isomorphic by YELLOW16:52;
    then imF, Omega Y are_isomorphic by WAYBEL_1:7;
   hence thesis by A3,WAYBEL15:11,WAYBEL20:18;
  end;

theorem Th30:
 for X being non empty 1-sorted, I being non empty set
 for J being TopSpace-yielding non-Empty ManySortedSet of I
 for f being map of X, I-TOP_prod J
 for i being Element of I
  holds (commute f).i = proj(J,i)*f
  proof let X be non empty 1-sorted, I be non empty set;
   let J be TopSpace-yielding non-Empty ManySortedSet of I;
   let f be map of X, I-TOP_prod J;
A1:  dom f = the carrier of X & rng f c= the carrier of I-TOP_prod J
     by FUNCT_2:def 1;
A2:  the carrier of I-TOP_prod J = product Carrier J by WAYBEL18:def 3;
A3:  dom Carrier J = I by PBOOLE:def 3;
      rng f c= Funcs(I, Union Carrier J)
     proof let g be set; assume g in rng f;
      then consider h being Function such that
A4:     g = h & dom h = I &
       for x being set st x in I holds h.x in (Carrier J).x
        by A2,A3,CARD_3:def 5;
         rng h c= Union Carrier J
        proof let y be set; assume y in rng h;
         then consider x being set such that
A5:        x in dom h & y = h.x by FUNCT_1:def 5;
            h.x in (Carrier J).x & dom Carrier J = I by A4,A5,PBOOLE:def 3;
         hence thesis by A4,A5,CARD_5:10;
        end;
      hence thesis by A4,FUNCT_2:def 2;
     end;
then A6:  f in Funcs(the carrier of X, Funcs(I, Union Carrier J))
     by A1,FUNCT_2:def 2;
    then commute f in Funcs(I, Funcs(the carrier of X, Union Carrier J))
     by PRALG_2:4;
then A7:  ex g being Function st commute f = g & dom g = I &
     rng g c= Funcs(the carrier of X, Union Carrier J) by FUNCT_2:def 2;
   let i be Element of I;
      (commute f).i in rng commute f by A7,FUNCT_1:def 5;
   then consider g being Function such that
A8: (commute f).i = g and
A9: dom g = the carrier of X and
   rng g c= Union Carrier J by A7,FUNCT_2:def 2;
A10: dom (proj(J, i)*f) = the carrier of X by FUNCT_2:def 1;
      now let x be set; assume x in the carrier of X;
     then reconsider a = x as Element of X;
     consider h being Function such that
A11:    f.a = h & dom h = I &
      for x being set st x in I holds h.x in (Carrier J).x
       by A2,A3,CARD_3:def 5;
A12:    dom proj(Carrier J, i) = product Carrier J by PRALG_3:def 2;
        (proj(J,i)*f).a = proj(J,i).(f.a) by FUNCT_2:21
        .= (proj (Carrier J, i)).(f.a) by WAYBEL18:def 4
        .= h.i by A2,A11,A12,PRALG_3:def 2;
     hence g.x = (proj(J,i)*f).x by A6,A8,A11,PRALG_2:5;
    end;
   hence (commute f).i = proj(J,i)*f by A8,A9,A10,FUNCT_1:9;
  end;

theorem Th31:
 for S being 1-sorted, M being set holds
  Carrier (M --> S) = M --> the carrier of S
  proof let S be 1-sorted, M be set;
      now let i be set; assume i in M;
      then (M --> S).i = S & (M --> the carrier of S).i = the carrier of S &
      ex R being 1-sorted st R = (M --> S).i &
        (Carrier (M --> S)).i = the carrier of R
       by FUNCOP_1:13,PRALG_1:def 13;
     hence (Carrier (M --> S)).i = (M --> the carrier of S).i;
    end;
   hence thesis by PBOOLE:3;
  end;

theorem Th32:
 for X,Y being non empty TopSpace, M being non empty set
 for f being continuous map of X, M-TOP_prod (M --> Y)
  holds commute f is Function of M, the carrier of oContMaps(X, Y)
  proof let X,Y be non empty TopSpace, M be non empty set;
   let f be continuous map of X, M-TOP_prod (M --> Y);
A1:  dom f = the carrier of X & rng f c= the carrier of M-TOP_prod (M --> Y)
     by FUNCT_2:def 1;
      rng f c= Funcs(M, the carrier of Y)
     proof let g be set; assume
A2:     g in rng f;
         the carrier of M-TOP_prod (M --> Y)
         = product Carrier (M --> Y) by WAYBEL18:def 3
        .= product (M --> the carrier of Y) by Th31;
       then g in product (M --> the carrier of Y) & dom (M --> the carrier of
Y) = M
        by A2,FUNCOP_1:19;
      then consider h being Function such that
A3:     g = h & dom h = M &
       for x being set st x in M holds h.x in (M --> the carrier of Y).x
        by CARD_3:def 5;
         rng h c= the carrier of Y
        proof let y be set; assume y in rng h;
         then consider x being set such that
A4:        x in dom h & y = h.x by FUNCT_1:def 5;
            (M --> the carrier of Y).x = the carrier of Y
           by A3,A4,FUNCOP_1:13;
         hence y in the carrier of Y by A3,A4;
        end;
      hence thesis by A3,FUNCT_2:def 2;
     end;
    then f in Funcs(the carrier of X, Funcs(M, the carrier of Y))
     by A1,FUNCT_2:def 2;
then A5:  commute f in Funcs(M, Funcs(the carrier of X, the carrier of Y))
     by PRALG_2:4;
    then A6: ex g being Function st commute f = g & dom g = M &
    rng g c= Funcs(the carrier of X, the carrier of Y) by FUNCT_2:def 2;
      rng commute f c= the carrier of oContMaps(X, Y)
     proof let g be set; assume g in rng commute f;
      then consider i being set such that
A7:     i in dom commute f & g = (commute f).i by FUNCT_1:def 5;
         ex h being Function st commute f = h & dom h = M &
       rng h c= Funcs(the carrier of X, the carrier of Y)
        by A5,FUNCT_2:def 2;
      then reconsider i as Element of M by A7;
         g = proj(M --> Y, i)*f & (M --> Y).i = Y by A7,Th30,FUNCOP_1:13;
       then g is continuous map of X,Y by WAYBEL18:7;
       then g is Element of oContMaps(X,Y) by Th2;
      hence thesis;
     end;
   hence thesis by A6,FUNCT_2:4;
  end;

theorem Th33:
 for X,Y being non empty TopSpace holds
  the carrier of oContMaps(X, Y) c= Funcs(the carrier of X, the carrier of Y)
  proof let X,Y be non empty TopSpace;
      oContMaps(X, Y) = ContMaps(X, Omega Y) by Def1;
    then oContMaps(X, Y) is SubRelStr of (Omega Y)|^the carrier of X
     by WAYBEL24:def 3;
    then the carrier of oContMaps(X, Y) c=
      the carrier of (Omega Y)|^the carrier of X by YELLOW_0:def 13;
    then the carrier of oContMaps(X, Y) c=
      Funcs(the carrier of X, the carrier of Omega Y) &
    the TopStruct of Y = the TopStruct of Omega Y
     by WAYBEL25:def 2,YELLOW_1:28;
   hence thesis;
  end;

theorem Th34:
 for X,Y being non empty TopSpace, M being non empty set
 for f being Function of M, the carrier of oContMaps(X, Y)
  holds commute f is continuous map of X, M-TOP_prod (M --> Y)
  proof let X,Y be non empty TopSpace, M be non empty set;
   let f be Function of M, the carrier of oContMaps(X, Y);
A1:  dom f = M & rng f c= the carrier of oContMaps(X, Y) by FUNCT_2:def 1;
      the carrier of oContMaps(X, Y) c=
      Funcs(the carrier of X, the carrier of Y) by Th33;
    then rng f c= Funcs(the carrier of X, the carrier of Y) by XBOOLE_1:1;
then A2: f in Funcs(M, Funcs(the carrier of X, the carrier of Y))
     by A1,FUNCT_2:def 2;
  then commute f in Funcs(the carrier of X, Funcs(M, the carrier of Y))
     by PRALG_2:4;
    then A3: ex g being Function st commute f = g & dom g = the carrier of X &
    rng g c= Funcs(M, the carrier of Y) by FUNCT_2:def 2;
A4:  the carrier of M-TOP_prod (M --> Y)
      = product Carrier (M --> Y) by WAYBEL18:def 3;
A5: Carrier (M --> Y) = M --> the carrier of Y by Th31;
    then the carrier of M-TOP_prod (M --> Y) = Funcs(M, the carrier of Y)
     by A4,CARD_3:20;
    then commute f is Function of the carrier of X,
      the carrier of M-TOP_prod (M --> Y) by A3,FUNCT_2:4;
   then reconsider g = commute f as map of X, M-TOP_prod (M --> Y);
   reconsider B = product_prebasis (M --> Y) as
      prebasis of M-TOP_prod (M --> Y) by WAYBEL18:def 3;
      now let P be Subset of M-TOP_prod (M --> Y); assume P in B;
     then consider i being set, T being TopStruct, V being Subset of T such
that
A6:    i in M & V is open & T = (M --> Y).i and
A7:    P = product ((Carrier (M --> Y)) +* (i,V)) by WAYBEL18:def 2;
A8:   T = Y by A6,FUNCOP_1:13;
     reconsider i as Element of M by A6;
     set FP = (Carrier (M --> Y)) +* (i,V);
A9:   dom FP = dom Carrier (M --> Y) by FUNCT_7:32;
A10:   dom Carrier (M --> Y) = M by A5,FUNCOP_1:19;
then A11:   FP.i = V by FUNCT_7:33;
     reconsider fi = f.i as continuous map of X, Y by Th2;
        now let x be set;
       hereby assume A12: x in g"P;
then x in the carrier of X & g.x in P by FUNCT_2:46;
        then consider gx being Function such that
A13:      g.x = gx & dom gx = dom FP &
         for z being set st z in dom FP holds gx.z in FP.z
          by A7,CARD_3:def 5;
        reconsider Q = fi"V as Subset of X;
        take Q;
        thus Q is open by A6,A8,TOPS_2:55;
        thus Q c= g"P
          proof let a be set; assume A14: a in Q;
then A15:         a in the carrier of X & fi.a in V by FUNCT_2:46;
              g.a in rng g by A3,A14,FUNCT_1:def 5;
           then consider ga being Function such that
A16:         g.a = ga & dom ga = M & rng ga c= the carrier of Y
             by A3,FUNCT_2:def 2;
              now let z be set; assume
A17:           z in M;
              then z <> i & (M --> the carrier of Y).z = the carrier of Y or
              z = i by FUNCOP_1:13;
then z <> i & ga.z in rng ga & FP.z = the carrier of Y or
              z = i by A5,A16,A17,FUNCT_1:def 5,FUNCT_7:34;
             hence ga.z in FP.z by A2,A11,A15,A16,PRALG_2:5;
            end;
            then ga in P by A7,A9,A10,A16,CARD_3:18;
           hence thesis by A14,A16,FUNCT_2:46;
          end;
A18:      gx.i in V by A9,A10,A11,A13;
           gx.i = fi.x by A2,A12,A13,PRALG_2:5;
        hence x in Q by A12,A18,FUNCT_2:46;
       end;
       thus (ex Q being Subset of X st Q is open & Q c= g"P & x in Q)
         implies x in g"P;
      end;
     hence g"P is open by TOPS_1:57;
    end;
   hence thesis by YELLOW_9:36;
  end;

theorem Th35:
 for X being non empty TopSpace, M being non empty set
 ex F being map of oContMaps(X, M-TOP_prod (M --> Sierpinski_Space)),
                   M-POS_prod (M --> oContMaps(X, Sierpinski_Space))
  st F is isomorphic &
     for f being continuous map of X, M-TOP_prod (M --> Sierpinski_Space)
      holds F.f = commute f
  proof let X be non empty TopSpace, M be non empty set;
   set S = Sierpinski_Space, S'M = M-TOP_prod (M --> S);
   set X__S'M = oContMaps(X, S'M), X_S = oContMaps(X, S);
   set X_S'_M = M-POS_prod (M --> X_S);
   deffunc F(Element of X__S'M) = commute $1;
   consider F being ManySortedSet of the carrier of X__S'M such that
A1:  for f being Element of X__S'M holds
       F.f = F(f) from LambdaDMS;
A2:  dom F = the carrier of X__S'M by PBOOLE:def 3;
      rng F c= the carrier of X_S'_M
     proof let g be set; assume g in rng F;
      then consider f being set such that
A3:     f in dom F & g = F.f by FUNCT_1:def 5;
         f is Element of X__S'M by A2,A3;
      then reconsider f as continuous map of X, S'M by Th2;
         g = commute f by A1,A2,A3;
      then reconsider g as Function of M, the carrier of X_S by Th32;
         dom g = M & rng g c= the carrier of X_S by FUNCT_2:def 1;
       then g in Funcs(M, the carrier of X_S) by FUNCT_2:def 2;
       then g in the carrier of X_S|^M by YELLOW_1:28;
      hence thesis by YELLOW_1:def 5;
     end;
    then F is Function of the carrier of X__S'M, the carrier of X_S'_M
     by A2,FUNCT_2:4;
   then reconsider F as map of X__S'M, X_S'_M;
   take F;
   deffunc F(Element of X_S'_M) = commute $1;
   consider G being ManySortedSet of the carrier of X_S'_M such that
A4:  for f being Element of X_S'_M holds
       G.f = F(f) from LambdaDMS;
A5:  dom G = the carrier of X_S'_M by PBOOLE:def 3;
      rng G c= the carrier of X__S'M
     proof let g be set; assume g in rng G;
      then consider f being set such that
A6:     f in dom G & g = G.f by FUNCT_1:def 5;
         f in the carrier of X_S|^M by A5,A6,YELLOW_1:def 5;
       then f in Funcs(M, the carrier of X_S) by YELLOW_1:28;
      then consider f' being Function such that
A7:     f = f' & dom f' = M & rng f' c= the carrier of X_S by FUNCT_2:def 2;
         f' is Function of M, the carrier of X_S &
       g = commute f' by A4,A5,A6,A7,FUNCT_2:4;
       then g is continuous map of X, S'M by Th34;
       then g is Element of X__S'M by Th2;
      hence thesis;
     end;
    then G is Function of the carrier of X_S'_M, the carrier of X__S'M
     by A5,FUNCT_2:4;
   then reconsider G as map of X_S'_M, X__S'M;
A8:  the carrier of X__S'M c= Funcs(the carrier of X, the carrier of S'M)
       by Th33;
A9:  the carrier of S'M = product Carrier (M --> S) by WAYBEL18:def 3
        .= product (M --> the carrier of S) by Th31
        .= Funcs(M, the carrier of S) by CARD_3:20;
A10:  the carrier of X_S'_M = the carrier of X_S|^M by YELLOW_1:def 5
        .= Funcs(M, the carrier of X_S) by YELLOW_1:28;
    the carrier of X_S c= Funcs(the carrier of X, the carrier of S)
     by Th33;
then A11:  the carrier of X_S'_M c=
      Funcs(M, Funcs(the carrier of X, the carrier of S)) by A10,FUNCT_5:63;
A12:  the RelStr of Omega S'M = M-POS_prod(M --> Omega S) by WAYBEL25:14;
A13:  F is monotone
     proof let a, b be Element of X__S'M such that
A14:    a <= b;
      reconsider f = a, g = b as continuous map of X, Omega S'M by Th1;
      reconsider f' = a, g' = b as continuous map of X, S'M by Th2;
         now let i be Element of M;
A15:      (M --> X_S).i = X_S by FUNCOP_1:13;
        then reconsider Fai = (F.a).i, Fbi = (F.b).i
           as continuous map of X, Omega S by Th1;
           now let j be set; assume j in the carrier of X;
          then reconsider x = j as Element of X;
          reconsider fx = f.x, gx = g.x
             as Element of M-POS_prod(M --> Omega S) by A12;
             a in the carrier of X__S'M & b in the carrier of X__S'M;
           then F.a = commute f & F.b = commute g &
           a in Funcs(the carrier of X, Funcs(M, the carrier of S)) &
           b in Funcs(the carrier of X, Funcs(M, the carrier of S))
            by A1,A8,A9;
then A16:        Fai.x = (f'.x).i & Fbi.x = (g'.x).i by PRALG_2:5;
             f <= g by A14,Th3;
           then ex a, b being Element of Omega S'M st a = f.x & b = g.x & a <=
b
            by YELLOW_2:def 1;
           then fx <= gx by A12,YELLOW_0:1;
           then fx.i <= gx.i & (M --> Omega S).i = Omega S
            by FUNCOP_1:13,WAYBEL_3:28;
          hence ex a, b being Element of Omega S
            st a = Fai.j & b = Fbi.j & a <= b by A16;
         end;
         then Fai <= Fbi by YELLOW_2:def 1;
        hence (F.a).i <= (F.b).i by A15,Th3;
       end;
      hence thesis by WAYBEL_3:28;
     end;
A17:  G is monotone
     proof let a,b be Element of X_S'_M such that
A18:    a <= b;
      reconsider f = G.a, g = G.b as continuous map of X, Omega S'M by Th1;
         now let i be set; assume i in the carrier of X;
        then reconsider x = i as Element of X;
        reconsider fx = f.x, gx = g.x as Element of M-POS_prod(M --> Omega S)
          by A12;
           now let j be Element of M;
A19:        (M --> X_S).j = X_S by FUNCOP_1:13;
          then reconsider aj = a.j, bj = b.j as
             continuous map of X, Omega S by Th1;
             a in the carrier of X_S'_M & b in the carrier of X_S'_M;
           then G.a = commute a & G.b = commute b &
           a in Funcs(M, Funcs(the carrier of X, the carrier of S)) &
           b in Funcs(M, Funcs(the carrier of X, the carrier of S))
            by A4,A11;
then A20:        fx.j = aj.x & gx.j = bj.x by PRALG_2:5;
             a.j <= b.j by A18,WAYBEL_3:28;
           then aj <= bj by A19,Th3;
           then (M --> Omega S).j = Omega S &
           ex a, b being Element of Omega S
            st a = aj.x & b = bj.x & a <= b by FUNCOP_1:13,YELLOW_2:def 1;
          hence fx.j <= gx.j by A20;
         end;
         then fx <= gx by WAYBEL_3:28;
         then f.x <= g.x by A12,YELLOW_0:1;
        hence ex a,b being Element of Omega S'M st a = f.i & b = g.i & a <= b;
       end;
       then f <= g by YELLOW_2:def 1;
      hence thesis by Th3;
     end;
      now let a be Element of X_S'_M;
A21:   a in Funcs(M, the carrier of X_S) by A10;
        the carrier of X_S c= Funcs(the carrier of X, the carrier of S)
       by Th33;
      then Funcs(M, the carrier of X_S) c=
       Funcs(M, Funcs(the carrier of X, the carrier of S)) by FUNCT_5:63;
then A22:   commute commute a = a by A21,PRALG_2:6;
     thus (F*G).a = F.(G.a) by FUNCT_2:21 .= commute (G.a) by A1
       .= a by A4,A22 .= (id X_S'_M).a by GRCAT_1:11;
    end;
then A23:  F*G = id X_S'_M by YELLOW_2:9;
      now let a be Element of X__S'M;
        a in the carrier of X__S'M;
then A24:   commute commute a = a by A8,A9,PRALG_2:6;
     thus (G*F).a = G.(F.a) by FUNCT_2:21 .= commute (F.a) by A4
       .= a by A1,A24 .= (id X__S'M).a by GRCAT_1:11;
    end;
    then G*F = id X__S'M by YELLOW_2:9;
   hence F is isomorphic by A13,A17,A23,YELLOW16:17;
   let f be continuous map of X, M-TOP_prod (M --> Sierpinski_Space);
      f is Element of X__S'M by Th2;
   hence thesis by A1;
  end;

theorem Th36:
 for X being non empty TopSpace, M being non empty set
  holds
   oContMaps(X, M-TOP_prod (M --> Sierpinski_Space)),
    M-POS_prod (M --> oContMaps(X, Sierpinski_Space)) are_isomorphic
  proof let X be non empty TopSpace, M be non empty set;
   consider F being map of oContMaps(X, M-TOP_prod (M --> Sierpinski_Space)),
                M-POS_prod (M --> oContMaps(X, Sierpinski_Space)) such that
A1:  F is isomorphic and
      for f being continuous map of X, M-TOP_prod (M --> Sierpinski_Space)
      holds F.f = commute f by Th35;
   take F; thus thesis by A1;
  end;

:: 4.6.  PROPOSITION
theorem Th37:
 for X being non empty TopSpace st InclPoset the topology of X is continuous
 for Y being injective T_0-TopSpace
 holds
  oContMaps(X, Y) is complete continuous
  proof let X be non empty TopSpace such that
A1:  InclPoset the topology of X is continuous;
   let Y be injective T_0-TopSpace;
   consider M being non empty set such that
A2:  Y is_Retract_of M-TOP_prod (M --> Sierpinski_Space) by WAYBEL18:20;
      oContMaps(X, M-TOP_prod (M --> Sierpinski_Space)),
    M-POS_prod (M --> oContMaps(X, Sierpinski_Space)) are_isomorphic
     by Th36;
then A3:  M-POS_prod (M --> oContMaps(X, Sierpinski_Space)),
    oContMaps(X, M-TOP_prod (M --> Sierpinski_Space)) are_isomorphic
     by WAYBEL_1:7;
      InclPoset the topology of X, oContMaps(X, Sierpinski_Space)
      are_isomorphic by Th6;
   then reconsider XS = oContMaps(X, Sierpinski_Space) as
      complete continuous (non empty Poset) by A1,WAYBEL15:11,WAYBEL20:18;
      for i be Element of M holds
     (M --> Sierpinski_Space).i is injective by FUNCOP_1:13;
   then reconsider MS = M-TOP_prod (M --> Sierpinski_Space) as
      injective T_0-TopSpace by WAYBEL18:8;
      for i be Element of M holds
     (M --> XS).i is complete continuous LATTICE by FUNCOP_1:13;
    then M-POS_prod (M --> XS) is complete continuous
     by WAYBEL20:34;
    then oContMaps(X, MS) is complete continuous
     by A3,WAYBEL15:11,WAYBEL20:18;
   hence thesis by A2,Th24;
  end;

definition
 cluster non trivial complete Scott TopLattice;
 existence
  proof set L = BoolePoset 1;
    A1: BoolePoset 1 = InclPoset bool 1 by YELLOW_1:4;
   consider T being Scott TopAugmentation of L;
   take T; the RelStr of T = the RelStr of L by YELLOW_9:def 4;
    then 0 <> 1 & the carrier of T = bool 1 & 0 in {0,1} & 1 in {0,1}
     by A1,TARSKI:def 2,YELLOW_1:1;
   hence thesis by REALSET1:def 20,YELLOW14:1;
  end;
end;


:: 4.7.  THEOREM  p.129.
theorem
   for X being non empty TopSpace
 for L being non trivial complete Scott TopLattice
  holds
     oContMaps(X, L) is complete continuous
   iff
     InclPoset the topology of X is continuous & L is continuous
  proof let X be non empty TopSpace;
   let L be non trivial complete Scott TopLattice;
A1:  L is monotone-convergence by WAYBEL25:29;
      Omega L = the TopRelStr of L by WAYBEL25:15;
then A2:  the RelStr of Omega L = the RelStr of L;
A3:  L is Scott TopAugmentation of L by YELLOW_9:44;
   hereby assume
A4:   oContMaps(X, L) is complete continuous;
    hence InclPoset the topology of X is continuous by A1,Th27;
       Omega L is continuous by A3,A4,Th29;
    hence L is continuous by A2,YELLOW12:15;
   end;
      L is continuous implies L is injective by A3,WAYBEL25:12;
   hence thesis by Th37;
  end;

definition
 let f be Function;
 cluster Union disjoin f -> Relation-like;
 coherence
  proof
      for x being set st x in Union disjoin f ex y,z being set st x = [y,z]
     by CARD_3:32;
   hence thesis by RELAT_1:def 1;
  end;
end;

definition
 let f be Function;
 func *graph f -> Relation equals:
Def4:  (Union disjoin f)~; :: card_3
 correctness;
end;

reserve x,y for set, f for Function;

theorem Th39:
 [x,y] in *graph f iff x in dom f & y in f.x
  proof
A1:  *graph f = (Union disjoin f)~ by Def4;
A2:  [y,x]`1 = y & [y,x]`2 = x by MCART_1:7;
      [x,y] in *graph f iff [y,x] in Union disjoin f by A1,RELAT_1:def 7;
   hence thesis by A2,CARD_3:33;
  end;

theorem Th40:
 for X being finite set holds proj1 X is finite & proj2 X is finite
  proof let X be finite set;
    deffunc F(set) = $1`1;
   consider f being Function such that
A1:  dom f = X & for x being set st x in X holds f.x = F(x) from Lambda;
A2:  proj1 X c= rng f
     proof let x be set; assume x in proj1 X;
      then consider y being set such that
A3:     [x,y] in X by FUNCT_5:def 1;
         [x,y]`1 = x by MCART_1:7;
       then f.([x,y]) = x by A1,A3;
      hence thesis by A1,A3,FUNCT_1:def 5;
     end;
      rng f is finite by A1,FINSET_1:26;
   hence proj1 X is finite by A2,FINSET_1:13;
   deffunc F(set) = $1`2;
   consider f being Function such that
A4:  dom f = X & for x being set st x in X holds f.x = F(x) from Lambda;
A5:  proj2 X c= rng f
     proof let x be set; assume x in proj2 X;
      then consider y being set such that
A6:     [y,x] in X by FUNCT_5:def 2;
         [y,x]`2 = x by MCART_1:7;
       then f.([y,x]) = x by A4,A6;
      hence thesis by A4,A6,FUNCT_1:def 5;
     end;
      rng f is finite by A4,FINSET_1:26;
   hence proj2 X is finite by A5,FINSET_1:13;
  end;

:: 4.8.  LEMMA  p.130.
theorem Th41:
 for X,Y being non empty TopSpace
 for S being Scott TopAugmentation of InclPoset the topology of Y
 for f being map of X, S
  st *graph f is open Subset of [:X,Y:]
  holds f is continuous
  proof let X,Y be non empty TopSpace;
   let S be Scott TopAugmentation of InclPoset the topology of Y;
   let f be map of X, S; assume
    *graph f is open Subset of [:X,Y:];
   then consider AA being Subset-Family of [:X,Y:] such that
A1: *graph f = union AA and
A2: for e being set st e in AA
     ex X1 being Subset of X, Y1 being Subset of Y st
       e = [:X1,Y1:] & X1 is open & Y1 is open by BORSUK_1:45;
A3:  the carrier of InclPoset the topology of Y = the topology of Y
     by YELLOW_1:1;
A4:  the RelStr of S = the RelStr of InclPoset the topology of Y
     by YELLOW_9:def 4;
A5:  dom f = the carrier of X by FUNCT_2:def 1;
      now let P be Subset of S; assume
A6:    P is open;
        now let x be set;
       hereby assume A7: x in f"P; then
A8:       x in the carrier of X & f.x in P by FUNCT_2:46;
        reconsider y = x as Element of X by A7;
           f.y in the topology of Y by A3,A4;
        then reconsider W = f.y as open Subset of Y
          by PRE_TOPC:def 5;
        defpred P[set,set] means
          x in $2`1 & $1 in $2`2 & [:$2`1,$2`2:] c= *graph f;
A9:      now let e be set; assume e in f.x;
           then [x,e] in *graph f by A5,A7,Th39;
          then consider V being set such that
A10:        [x,e] in V & V in AA by A1,TARSKI:def 4;
          consider A being Subset of X, B being Subset of Y such that
A11:        V = [:A,B:] & A is open & B is open by A2,A10;
          reconsider u = [A,B] as set;
          take u;
             A in the topology of X & B in
 the topology of Y by A11,PRE_TOPC:def 5;
          hence u in [:the topology of X, the topology of Y:] by ZFMISC_1:106;
             A = u`1 & B = u`2 by MCART_1:7;
          hence P[e,u] by A1,A10,A11,ZFMISC_1:92,106;
         end;
        consider g being Function such that
A12:       dom g = f.x & rng g c= [:the topology of X, the topology of Y:] and
A13:       for a being set st a in f.x holds P[a,g.a]
          from NonUniqBoundFuncEx(A9);
A14:      proj1 rng g c= the topology of X by A12,FUNCT_5:13;
A15:      proj2 rng g c= the topology of Y by A12,FUNCT_5:13;
A16:      proj2 rng g c= bool (f.x)
          proof let z be set; assume z in proj2 rng g;
           then consider z1 being set such that
A17:         [z1,z] in rng g by FUNCT_5:def 2;
           consider a being set such that
A18:         a in dom g & [z1,z] = g.a by A17,FUNCT_1:def 5;
              [z1,z]`1 = z1 & [z1,z]`2 = z by MCART_1:7;
then A19:         x in z1 & [:z1,z:] c= *graph f by A12,A13,A18;
              z c= f.x
             proof let a be set; assume a in z;
               then [x,a] in [:z1,z:] by A19,ZFMISC_1:106;
              hence thesis by A19,Th39;
             end;
           hence thesis;
          end;
        set J = {union A where A is Subset of proj2 rng g: A is finite};
        consider A0 being empty Subset of proj2 rng g;
A20:       A0 in J by ZFMISC_1:2;
           J c= the topology of Y
          proof let x be set; assume x in J;
           then consider A being Subset of proj2 rng g such that
A21:         x = union A & A is finite;
A22:         A c= the topology of Y by A15,XBOOLE_1:1;
            then A is Subset of bool the carrier of Y by XBOOLE_1:1;
            then A is Subset-Family of Y by SETFAM_1:def 7;
           hence thesis by A21,A22,PRE_TOPC:def 1;
          end;
        then reconsider J as non empty Subset of
           InclPoset the topology of Y by A3,A20;
           J is directed
          proof let a,b be Element of InclPoset the topology of Y;
           assume a in J;
           then consider A being Subset of proj2 rng g such that
A23:         a = union A & A is finite;
           assume b in J;
           then consider B being Subset of proj2 rng g such that
A24:         b = union B & B is finite;
           take ab = a"\/"b;
           reconsider AB = A \/ B as finite Subset of proj2 rng g
             by A23,A24,FINSET_1:14;
A25:         union AB = a \/ b & a \/
 b = ab by A23,A24,WAYBEL14:18,ZFMISC_1:96;
           hence ab in J;
              a c= ab & b c= ab by A25,XBOOLE_1:7;
           hence thesis by YELLOW_1:3;
          end;
        then reconsider J' = J as non empty directed Subset of S
          by A4,WAYBEL_0:3;
           union J = f.y
          proof
           thus union J c= f.y
             proof let a be set; assume a in union J;
              then consider u being set such that
A26:            a in u & u in J by TARSKI:def 4;
              consider A being Subset of proj2 rng g such that
A27:            u = union A & A is finite by A26;
                 A c= bool (f.y) by A16,XBOOLE_1:1;
               then u c= union bool (f.y) by A27,ZFMISC_1:95;
               then u c= f.y by ZFMISC_1:99;
              hence thesis by A26;
             end;
           let a be set; assume a in f.y;
then A28:         g.a in rng g & a in (g.a)`2 by A12,A13,FUNCT_1:def 5;
            then g.a = [(g.a)`1, (g.a)`2] by A12,MCART_1:23;
            then (g.a)`2 in proj2 rng g by A28,FUNCT_5:def 2;
           then reconsider A = {(g.a)`2} as Subset of proj2 rng g by ZFMISC_1:
37;
              union A = (g.a)`2 by ZFMISC_1:31;
            then (g.a)`2 in J;
           hence thesis by A28,TARSKI:def 4;
          end;
         then sup J = f.y & ex_sup_of J,S by YELLOW_0:17,YELLOW_1:22;
         then sup J' = f.y & P is inaccessible
          by A4,A6,WAYBEL11:def 4,YELLOW_0:26;
         then J meets P by A8,WAYBEL11:def 1;
        then consider a being set such that
A29:      a in J & a in P by XBOOLE_0:3;
        reconsider a as Element of S by A29;
        consider A being Subset of proj2 rng g such that
A30:      a = union A and
A31:      A is finite by A29;
        defpred P[set,set] means
          ex c1 being set st [c1,$1] = g.$2 & x in c1 & $2 in $1 &
             $2 in f.x & [:c1,$1:] c= *graph f;
A32:      now let c be set; assume c in A;
          then consider c1 being set such that
A33:        [c1,c] in rng g by FUNCT_5:def 2;
          consider a being set such that
A34:        a in dom g & [c1,c] = g.a by A33,FUNCT_1:def 5;
          take a; thus a in W by A12,A34;
             [c1,c]`1 = c1 & [c1,c]`2 = c by MCART_1:7;
then x in c1 & a in c & [:c1,c:] c= *graph f by A12,A13,A34;
          hence P[c,a] by A12,A34;
         end;
        consider hh being Function such that
A35:      dom hh = A & rng hh c= W and
A36:      for c being set st c in A holds P[c,hh.c]
           from NonUniqBoundFuncEx(A32);
        set B = proj1 (g.:rng hh);
           g.:rng hh c= rng g by RELAT_1:144;
         then B c= proj1 rng g by FUNCT_5:5;
then A37:      B c= the topology of X by A14,XBOOLE_1:1;
         then B c= bool the carrier of X by XBOOLE_1:1;
        then reconsider B as Subset-Family of X by SETFAM_1:def
7;
        reconsider B as Subset-Family of X;
        reconsider Q = Intersect B as Subset of X;
        take Q;
           rng hh is finite by A31,A35,FINSET_1:26;
         then g.:rng hh is finite by FINSET_1:17;
         then B is finite by Th40;
         then Q in FinMeetCl the topology of X by A37,CANTOR_1:def 4;
         then Q in the topology of X by CANTOR_1:5;
        hence Q is open by PRE_TOPC:def 5;
        thus Q c= f"P
          proof let z be set; assume
A38:         z in Q;
           then reconsider zz = z as Element of X;
           reconsider fz = f.zz, aa = a as Element of
              InclPoset the topology of Y by A4;
              a c= f.zz
             proof let p be set; assume p in a;
              then consider q being set such that
A39:            p in q & q in A by A30,TARSKI:def 4;
              consider q1 being set such that
A40:            [q1,q] = g.(hh.q) & x in q1 & hh.q in q & hh.q in f.x &
               [:q1,q:] c= *graph f by A36,A39;
             hh.q in rng hh by A35,A39,FUNCT_1:def 5;
               then [q1,q] in g.:rng hh by A12,A40,FUNCT_1:def 12;
               then q1 in B by FUNCT_5:def 1;
               then zz in q1 by A38,CANTOR_1:10;
               then [zz,p] in [:q1,q:] by A39,ZFMISC_1:106;
              hence p in f.zz by A40,Th39;
             end;
            then aa <= fz by YELLOW_1:3;
            then a <= f.zz & P is upper by A4,A6,WAYBEL11:def 4,YELLOW_0:1;
            then f.zz in P by A29,WAYBEL_0:def 20;
           hence thesis by FUNCT_2:46;
          end;
           now let c1 be set; assume c1 in B;
          then consider c being set such that
A41:        [c1,c] in g.:rng hh by FUNCT_5:def 1;
          consider b being set such that
A42:        b in dom g & b in rng hh & [c1,c] = g.b by A41,FUNCT_1:def 12;
          consider c' being set such that
A43:        c' in dom hh & b = hh.c' by A42,FUNCT_1:def 5;
          consider c'1 being set such that
A44:        [c'1,c'] = g.(hh.c') & x in c'1 & hh.c' in c' & hh.c' in f.x &
           [:c'1,c':] c= *graph f by A35,A36,A43;
          thus x in c1 by A42,A43,A44,ZFMISC_1:33;
         end;
        hence x in Q by A7,CANTOR_1:10;
       end;
       assume ex Q being Subset of X st Q is open & Q c= f"P & x in Q;
       hence x in f"P;
      end;
     hence f"P is open by TOPS_1:57;
    end;
   hence thesis by TOPS_2:55;
  end;

definition
 let W be Relation, X be set;
 func (W,X)*graph -> Function means:
Def5:
  dom it = X & for x st x in X holds it.x = W.:{x};
 existence
  proof deffunc F(set) = W.:{$1};
    thus ex f being Function st dom f = X & for x st x in X holds f.x = F(x)
    from Lambda;
  end;
 correctness
  proof let f,g be Function such that
A1: dom f = X and
A2: for x st x in X holds f.x = W.:{x} and
A3: dom g = X and
A4: for x st x in X holds g.x = W.:{x};
      now let x; assume
A5:    x in X;
     hence f.x = W.:{x} by A2 .= g.x by A4,A5;
    end;
   hence thesis by A1,A3,FUNCT_1:9;
  end;
end;

theorem Th42:
 for W being Relation, X being set st dom W c= X
  holds *graph((W,X)*graph) = W
  proof let W be Relation, X be set such that
A1:  dom W c= X;
A2:  dom ((W,X)*graph) = X by Def5;
      now let x,y be set;
     hereby assume [x,y] in *graph((W,X)*graph);
       then x in X & y in ((W,X)*graph).x by A2,Th39;
       then y in W.:{x} by Def5;
      then consider z being set such that
A3:     [z,y] in W & z in {x} by RELAT_1:def 13;
      thus [x,y] in W by A3,TARSKI:def 1;
     end;
     assume
A4:    [x,y] in W;
      then A5: x in {x} & x in dom W by RELAT_1:def 4,TARSKI:def 1;
then y in W.:{x} & x in X by A1,A4,RELAT_1:def 13;
      then y in ((W,X)*graph).x by Def5;
     hence [x,y] in *graph((W,X)*graph) by A1,A2,A5,Th39;
    end;
   hence thesis by RELAT_1:def 2;
  end;

definition
 let X, Y be TopSpace;
 cluster -> Relation-like Subset of [:X,Y:];
 coherence
  proof let r be Subset of [:X,Y:];
      r is Subset of [:the carrier of X, the carrier of Y:]
     by BORSUK_1:def 5;
   hence thesis;
  end;
 cluster -> Relation-like Element of the topology of [:X,Y:];
 coherence
  proof let r be Element of the topology of [:X,Y:];
      r is Subset of [:the carrier of X, the carrier of Y:] by BORSUK_1:def 5;
   hence thesis;
  end;
end;

theorem Th43:
 for X,Y being non empty TopSpace
 for W being open Subset of [:X,Y:]
 for x being Point of X
   holds W.:{x} is open Subset of Y
  proof let X,Y be non empty TopSpace, W be open Subset of [:X,Y:];
   let x be Point of X;
      the carrier of [:X,Y:] = [:the carrier of X, the carrier of Y:]
     by BORSUK_1:def 5;
   then reconsider W as Relation of the carrier of X, the carrier of Y
     by RELSET_1:def 1;
   reconsider A = W.:{x} as Subset of Y;
      now let y;
     hereby assume y in A;
      then consider z being set such that
A1:     [z,y] in W & z in {x} by RELAT_1:def 13;
      consider AA being Subset-Family of [:X,Y:] such that
A2:     W = union AA and
A3:     for e being set st e in AA
        ex X1 being Subset of X,
           Y1 being Subset of Y st
         e = [:X1,Y1:] & X1 is open & Y1 is open by BORSUK_1:45;
         z = x by A1,TARSKI:def 1;
      then consider e being set such that
A4:     [x,y] in e & e in AA by A1,A2,TARSKI:def 4;
      consider X1 being Subset of X, Y1 being Subset of Y such that
A5:     e = [:X1,Y1:] & X1 is open & Y1 is open by A3,A4;
A6:     x in X1 by A4,A5,ZFMISC_1:106;
      take Y1; thus Y1 is open by A5;
      thus Y1 c= A
        proof let z be set; assume z in Y1;
          then [x,z] in e by A5,A6,ZFMISC_1:106;
          then [x,z] in W & x in {x} by A2,A4,TARSKI:def 1,def 4;
         hence thesis by RELAT_1:def 13;
        end;
      thus y in Y1 by A4,A5,ZFMISC_1:106;
     end;
     thus (ex Q being Subset of Y st Q is open & Q c= A & y in Q)
       implies y in A;
    end;
   hence thesis by TOPS_1:57;
  end;

:: 4.9.  PROPOSITION a) p.130.
theorem Th44:
 for X,Y being non empty TopSpace
 for S being Scott TopAugmentation of InclPoset the topology of Y
 for W being open Subset of [:X,Y:]
  holds (W, the carrier of X)*graph is continuous map of X, S
  proof let X,Y be non empty TopSpace;
   let S be Scott TopAugmentation of InclPoset the topology of Y;
   let W be open Subset of [:X,Y:];
   set f = (W, the carrier of X)*graph;
      the carrier of [:X,Y:] = [:the carrier of X, the carrier of Y:]
     by BORSUK_1:def 5;
   then reconsider W as Relation of the carrier of X, the carrier of Y
     by RELSET_1:def 1;
A1:  dom W c= the carrier of X;
A2:  dom f = the carrier of X by Def5;
A3:  the carrier of InclPoset the topology of Y = the topology of Y
     by YELLOW_1:1;
A4:  the RelStr of S = the RelStr of InclPoset the topology of Y
     by YELLOW_9:def 4;
      rng f c= the carrier of S
     proof let y; assume y in rng f;
      then consider x such that
A5:     x in dom f & y = f.x by FUNCT_1:def 5;
      reconsider x as Element of X by A2,A5;
         y = W.:{x} by A5,Def5;
       then y is open Subset of Y by Th43;
      hence thesis by A3,A4,PRE_TOPC:def 5;
     end;
    then f is Function of the carrier of X, the carrier of S by A2,FUNCT_2:4;
   then reconsider f as map of X,S;
      *graph f = W by A1,Th42;
   hence thesis by Th41;
  end;

:: 4.9.  PROPOSITION b) p.130.
theorem Th45:
 for X,Y being non empty TopSpace
 for S being Scott TopAugmentation of InclPoset the topology of Y
 for W1, W2 being open Subset of [:X,Y:] st W1 c= W2
 for f1, f2 being Element of oContMaps(X, S)
  st f1 = (W1, the carrier of X)*graph & f2 = (W2, the carrier of X)*graph
  holds f1 <= f2
  proof let X,Y be non empty TopSpace;
   let S be Scott TopAugmentation of InclPoset the topology of Y;
   let W1,W2 be open Subset of [:X,Y:] such that
A1:  W1 c= W2;
   let f1,f2 be Element of oContMaps(X, S) such that
A2:  f1 = (W1, the carrier of X)*graph & f2 = (W2, the carrier of X)*graph;
A3:  the RelStr of S = the RelStr of InclPoset the topology of Y
     by YELLOW_9:def 4;
      S is TopAugmentation of S by YELLOW_9:44;
then A4:  the RelStr of S = the RelStr of Omega S by WAYBEL25:16;
   reconsider g1 = f1, g2 = f2 as continuous map of X, Omega S by Th1;
      now let j be set; assume j in the carrier of X;
     then reconsider x = j as Element of X;
     take a = g1.x, b = g2.x;
     thus a = g1.j & b = g2.j;
     reconsider g1x = g1.x, g2x = g2.x as
        Element of InclPoset the topology of Y by A3,A4;
        g1.x = W1.:{x} & g2.x = W2.:{x} by A2,Def5;
      then g1.x c= g2.x by A1,RELAT_1:157;
      then g1x <= g2x by YELLOW_1:3;
     hence a <= b by A3,A4,YELLOW_0:1;
    end;
    then g1 <= g2 by YELLOW_2:def 1;
   hence thesis by Th3;
  end;

:: 4.9.  PROPOSITION  p.130.
theorem
   for X,Y being non empty TopSpace
 for S being Scott TopAugmentation of InclPoset the topology of Y
 ex F being map of InclPoset the topology of [:X, Y:], oContMaps(X, S) st
  F is monotone &
  for W being open Subset of [:X,Y:] holds F.W = (W, the carrier of X)*graph
  proof let X, Y be non empty TopSpace;
   let S be Scott TopAugmentation of InclPoset the topology of Y;
   deffunc F(Element of the topology of [:X,Y:])
     = ($1, the carrier of X)*graph;
   consider F being ManySortedSet of the topology of [:X,Y:] such that
A1:  for R being Element of the topology of [:X,Y:]
     holds F.R = F(R) from LambdaDMS;
A2:  the carrier of InclPoset the topology of [:X,Y:] = the topology of [:X,Y:]
     by YELLOW_1:1;
A3:  dom F = the topology of [:X,Y:] by PBOOLE:def 3;
      rng F c= the carrier of oContMaps(X, S)
     proof let y be set; assume y in rng F;
      then consider x such that
A4:     x in dom F & y = F.x by FUNCT_1:def 5;
      reconsider x as Element of the topology of [:X,Y:] by A4,PBOOLE:def 3;
         y = (x, the carrier of X)*graph & x is open Subset of [:X,Y:]
        by A1,A4,PRE_TOPC:def 5;
       then y is continuous map of X,S by Th44;
       then y is Element of oContMaps(X, S) by Th2;
      hence thesis;
     end;
    then F is Function of the topology of [:X,Y:], the carrier of oContMaps(X,
S)
     by A3,FUNCT_2:4;
   then reconsider F as map of InclPoset the topology of [:X, Y:], oContMaps(X,
S)
    by A2;
   take F;
   thus F is monotone
     proof let x,y be Element of InclPoset the topology of [:X,Y:];
         x in the topology of [:X,Y:] & y in the topology of [:X,Y:] by A2;
      then reconsider W1 = x, W2 = y as open Subset of [:X,Y:]
        by PRE_TOPC:def 5;
      assume x <= y;
       then W1 c= W2 & F.x = (W1, the carrier of X)*graph &
       F.y = (W2, the carrier of X)*graph by A1,A2,YELLOW_1:3;
      hence thesis by Th45;
     end;
   let W be open Subset of [:X,Y:];
      W in the topology of [:X,Y:] by PRE_TOPC:def 5;
   hence F.W = (W, the carrier of X)*graph by A1;
  end;


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