let N be set ; ex R being Relation st
( R is well-ordering & field R = N )
consider M being set such that
A1:
( N in M & ( for X, Y being set st X in M & Y c= X holds
Y in M ) )
and
A2:
for X being set st X in M holds
bool X in M
and
A3:
for X being set holds
( not X c= M or X,M are_equipotent or X in M )
by ZFMISC_1:112;
defpred S1[ set ] means not $1,M are_equipotent ;
consider D being set such that
A4:
for A being set holds
( A in D iff ( A in bool M & S1[A] ) )
from XFAMILY:sch 1();
A5:
union D c= M
set F = id D;
for Z being set st Z in D holds
( not (id D) . Z in Z & (id D) . Z in union D )
proof
let Z be
set ;
( Z in D implies ( not (id D) . Z in Z & (id D) . Z in union D ) )
assume A8:
Z in D
;
( not (id D) . Z in Z & (id D) . Z in union D )
not
Z in Z
;
hence
not
(id D) . Z in Z
by A8, FUNCT_1:18;
(id D) . Z in union D
for
X being
set st
X in D holds
X in union D
proof
let X be
set ;
( X in D implies X in union D )
A9:
X in {X}
by TARSKI:def 1;
assume
X in D
;
X in union D
then A10:
(
X in bool M & not
X,
M are_equipotent )
by A4;
A11:
not
{X},
M are_equipotent
proof
A12:
X <> bool X
assume
{X},
M are_equipotent
;
contradiction
then consider Z being
set such that
for
x being
object st
x in {X} holds
ex
y being
object st
(
y in M &
[x,y] in Z )
and A13:
for
y being
object st
y in M holds
ex
x being
object st
(
x in {X} &
[x,y] in Z )
and A14:
for
x,
z1,
y,
z2 being
object st
[x,z1] in Z &
[y,z2] in Z holds
(
x = y iff
z1 = z2 )
;
bool X in M
by A2, A3, A10;
then consider y being
object such that A15:
y in {X}
and A16:
[y,(bool X)] in Z
by A13;
consider x being
object such that A17:
x in {X}
and A18:
[x,X] in Z
by A3, A10, A13;
x = X
by A17, TARSKI:def 1;
then
y = x
by A15, TARSKI:def 1;
hence
contradiction
by A14, A12, A18, A16;
verum
end;
X in M
by A3, A10;
then
for
x being
object st
x in {X} holds
x in M
by TARSKI:def 1;
then
{X} c= M
;
then
{X} in D
by A4, A11;
hence
X in union D
by A9, TARSKI:def 4;
verum
end;
then
Z in union D
by A8;
hence
(id D) . Z in union D
by A8, FUNCT_1:18;
verum
end;
then consider S being Relation such that
A19:
field S c= union D
and
A20:
S is well-ordering
and
A21:
not field S in D
and
for y being set st y in field S holds
( S -Seg y in D & (id D) . (S -Seg y) = y )
by Th5;
( not field S c= M or field S,M are_equipotent )
by A4, A21;
then consider Z being set such that
A22:
for x being object st x in field S holds
ex y being object st
( y in M & [x,y] in Z )
and
A23:
for y being object st y in M holds
ex x being object st
( x in field S & [x,y] in Z )
and
A24:
for x, z1, y, z2 being object st [x,z1] in Z & [y,z2] in Z holds
( x = y iff z1 = z2 )
by A5, A19;
defpred S2[ object , object ] means [$2,$1] in Z;
A25:
for x being object st x in M holds
ex y being object st S2[x,y]
A26:
for x, z1, z2 being object st x in M & S2[x,z1] & S2[x,z2] holds
z1 = z2
by A24;
consider H being Function such that
A27:
dom H = M
and
A28:
for x being object st x in M holds
S2[x,H . x]
from FUNCT_1:sch 2(A26, A25);
defpred S3[ object , object ] means $2 = {$1};
defpred S4[ object ] means ex x, y being object st
( $1 = [x,y] & [(H . x),(H . y)] in S );
consider W0 being set such that
A29:
for z being object holds
( z in W0 iff ( z in [:M,M:] & S4[z] ) )
from XBOOLE_0:sch 1();
A30:
for x being object st x in field S holds
x in rng H
for z1, z2 being object st z1 in dom H & z2 in dom H & H . z1 = H . z2 holds
z1 = z2
then A35:
H is one-to-one
by FUNCT_1:def 4;
for z being object st z in W0 holds
ex x, y being object st z = [x,y]
then reconsider W0 = W0 as Relation by RELAT_1:def 1;
A36:
for z being object st z in field W0 holds
z in M
A39:
for x being object st x in N holds
ex y being object st S3[x,y]
;
A40:
for x, z1, z2 being object st x in N & S3[x,z1] & S3[x,z2] holds
z1 = z2
;
consider H1 being Function such that
A41:
dom H1 = N
and
A42:
for x being object st x in N holds
S3[x,H1 . x]
from FUNCT_1:sch 2(A40, A39);
for z1, z2 being object st z1 in dom H1 & z2 in dom H1 & H1 . z1 = H1 . z2 holds
z1 = z2
then A47:
H1 is one-to-one
by FUNCT_1:def 4;
set S1 = W0 |_2 (rng H1);
for x being object st x in rng H holds
x in field S
then A49:
rng H = field S
by A30, TARSKI:2;
for z being object st z in M holds
z in field W0
proof
let z be
object ;
( z in M implies z in field W0 )
assume A50:
z in M
;
z in field W0
ex
z1 being
object st
(
[z,z1] in W0 or
[z1,z] in W0 )
proof
H . z in field S
by A27, A49, A50, FUNCT_1:def 3;
then consider z2 being
object such that A51:
(
[(H . z),z2] in S or
[z2,(H . z)] in S )
by Th1;
A52:
(
[(H . z),z2] in S implies ex
z1 being
object st
(
[z,z1] in W0 or
[z1,z] in W0 ) )
proof
assume A53:
[(H . z),z2] in S
;
ex z1 being object st
( [z,z1] in W0 or [z1,z] in W0 )
then
z2 in rng H
by A49, RELAT_1:15;
then consider z3 being
object such that A54:
z3 in dom H
and A55:
z2 = H . z3
by FUNCT_1:def 3;
take
z3
;
( [z,z3] in W0 or [z3,z] in W0 )
[z,z3] in [:M,M:]
by A27, A50, A54, ZFMISC_1:87;
hence
(
[z,z3] in W0 or
[z3,z] in W0 )
by A29, A53, A55;
verum
end;
(
[z2,(H . z)] in S implies ex
z1 being
object st
(
[z,z1] in W0 or
[z1,z] in W0 ) )
proof
assume A56:
[z2,(H . z)] in S
;
ex z1 being object st
( [z,z1] in W0 or [z1,z] in W0 )
then
z2 in rng H
by A49, RELAT_1:15;
then consider z3 being
object such that A57:
z3 in dom H
and A58:
z2 = H . z3
by FUNCT_1:def 3;
take
z3
;
( [z,z3] in W0 or [z3,z] in W0 )
[z3,z] in [:M,M:]
by A27, A50, A57, ZFMISC_1:87;
hence
(
[z,z3] in W0 or
[z3,z] in W0 )
by A29, A56, A58;
verum
end;
hence
ex
z1 being
object st
(
[z,z1] in W0 or
[z1,z] in W0 )
by A51, A52;
verum
end;
hence
z in field W0
by Th1;
verum
end;
then A59:
field W0 = M
by A36, TARSKI:2;
for a, b being object holds
( [a,b] in W0 iff ( a in field W0 & b in field W0 & [(H . a),(H . b)] in S ) )
proof
let a,
b be
object ;
( [a,b] in W0 iff ( a in field W0 & b in field W0 & [(H . a),(H . b)] in S ) )
A60:
(
[a,b] in W0 implies (
a in field W0 &
b in field W0 &
[(H . a),(H . b)] in S ) )
proof
assume A61:
[a,b] in W0
;
( a in field W0 & b in field W0 & [(H . a),(H . b)] in S )
then A62:
[a,b] in [:M,M:]
by A29;
consider x,
y being
object such that A63:
[a,b] = [x,y]
and A64:
[(H . x),(H . y)] in S
by A29, A61;
a = x
by A63, XTUPLE_0:1;
hence
(
a in field W0 &
b in field W0 &
[(H . a),(H . b)] in S )
by A59, A62, A63, A64, XTUPLE_0:1, ZFMISC_1:87;
verum
end;
(
a in field W0 &
b in field W0 &
[(H . a),(H . b)] in S implies
[a,b] in W0 )
hence
(
[a,b] in W0 iff (
a in field W0 &
b in field W0 &
[(H . a),(H . b)] in S ) )
by A60;
verum
end;
then
H is_isomorphism_of W0,S
by A27, A35, A49, A59;
then A67:
H " is_isomorphism_of S,W0
by WELLORD1:39;
then
W0 is well-ordering
by A20, WELLORD1:44;
then A68:
W0 |_2 (rng H1) is well-ordering
by WELLORD1:25;
defpred S5[ object ] means ex x, y being object st
( $1 = [x,y] & [(H1 . x),(H1 . y)] in W0 |_2 (rng H1) );
consider W00 being set such that
A69:
for z being object holds
( z in W00 iff ( z in [:N,N:] & S5[z] ) )
from XBOOLE_0:sch 1();
for z being object st z in W00 holds
ex x, y being object st z = [x,y]
then reconsider W00 = W00 as Relation by RELAT_1:def 1;
A70:
for z being object st z in field W00 holds
z in N
rng H1 c= M
then A76:
field (W0 |_2 (rng H1)) = rng H1
by A20, A59, A67, WELLORD1:31, WELLORD1:44;
for z being object st z in N holds
z in field W00
proof
let z be
object ;
( z in N implies z in field W00 )
assume A77:
z in N
;
z in field W00
ex
z1 being
object st
(
[z,z1] in W00 or
[z1,z] in W00 )
proof
H1 . z in field (W0 |_2 (rng H1))
by A41, A76, A77, FUNCT_1:def 3;
then consider z2 being
object such that A78:
(
[(H1 . z),z2] in W0 |_2 (rng H1) or
[z2,(H1 . z)] in W0 |_2 (rng H1) )
by Th1;
A79:
(
[(H1 . z),z2] in W0 |_2 (rng H1) implies ex
z1 being
object st
(
[z,z1] in W00 or
[z1,z] in W00 ) )
proof
assume A80:
[(H1 . z),z2] in W0 |_2 (rng H1)
;
ex z1 being object st
( [z,z1] in W00 or [z1,z] in W00 )
then
z2 in rng H1
by A76, RELAT_1:15;
then consider z3 being
object such that A81:
z3 in dom H1
and A82:
z2 = H1 . z3
by FUNCT_1:def 3;
take
z3
;
( [z,z3] in W00 or [z3,z] in W00 )
[z,z3] in [:N,N:]
by A41, A77, A81, ZFMISC_1:87;
hence
(
[z,z3] in W00 or
[z3,z] in W00 )
by A69, A80, A82;
verum
end;
(
[z2,(H1 . z)] in W0 |_2 (rng H1) implies ex
z1 being
object st
(
[z,z1] in W00 or
[z1,z] in W00 ) )
proof
assume A83:
[z2,(H1 . z)] in W0 |_2 (rng H1)
;
ex z1 being object st
( [z,z1] in W00 or [z1,z] in W00 )
then
z2 in rng H1
by A76, RELAT_1:15;
then consider z3 being
object such that A84:
z3 in dom H1
and A85:
z2 = H1 . z3
by FUNCT_1:def 3;
take
z3
;
( [z,z3] in W00 or [z3,z] in W00 )
[z3,z] in [:N,N:]
by A41, A77, A84, ZFMISC_1:87;
hence
(
[z,z3] in W00 or
[z3,z] in W00 )
by A69, A83, A85;
verum
end;
hence
ex
z1 being
object st
(
[z,z1] in W00 or
[z1,z] in W00 )
by A78, A79;
verum
end;
hence
z in field W00
by Th1;
verum
end;
then A86:
field W00 = N
by A70, TARSKI:2;
for a, b being object holds
( [a,b] in W00 iff ( a in field W00 & b in field W00 & [(H1 . a),(H1 . b)] in W0 |_2 (rng H1) ) )
proof
let a,
b be
object ;
( [a,b] in W00 iff ( a in field W00 & b in field W00 & [(H1 . a),(H1 . b)] in W0 |_2 (rng H1) ) )
A87:
(
[a,b] in W00 implies (
a in field W00 &
b in field W00 &
[(H1 . a),(H1 . b)] in W0 |_2 (rng H1) ) )
proof
assume A88:
[a,b] in W00
;
( a in field W00 & b in field W00 & [(H1 . a),(H1 . b)] in W0 |_2 (rng H1) )
then A89:
[a,b] in [:N,N:]
by A69;
consider x,
y being
object such that A90:
[a,b] = [x,y]
and A91:
[(H1 . x),(H1 . y)] in W0 |_2 (rng H1)
by A69, A88;
a = x
by A90, XTUPLE_0:1;
hence
(
a in field W00 &
b in field W00 &
[(H1 . a),(H1 . b)] in W0 |_2 (rng H1) )
by A86, A89, A90, A91, XTUPLE_0:1, ZFMISC_1:87;
verum
end;
(
a in field W00 &
b in field W00 &
[(H1 . a),(H1 . b)] in W0 |_2 (rng H1) implies
[a,b] in W00 )
hence
(
[a,b] in W00 iff (
a in field W00 &
b in field W00 &
[(H1 . a),(H1 . b)] in W0 |_2 (rng H1) ) )
by A87;
verum
end;
then
H1 is_isomorphism_of W00,W0 |_2 (rng H1)
by A41, A47, A76, A86;
then
H1 " is_isomorphism_of W0 |_2 (rng H1),W00
by WELLORD1:39;
hence
ex R being Relation st
( R is well-ordering & field R = N )
by A68, A86, WELLORD1:44; verum