let W, X be set ; :: thesis: ( W is Tarski & W is epsilon-transitive & X in W implies the_rank_of X in W )
assume A1:
( W is Tarski & W is epsilon-transitive )
; :: thesis: ( not X in W or the_rank_of X in W )
then A2:
W is subset-closed
;
defpred S2[ Ordinal] means ex X being set st
( $1 = the_rank_of X & X in W & not $1 in W );
assume
( X in W & not the_rank_of X in W )
; :: thesis: contradiction
then A3:
ex A being Ordinal st S2[A]
;
consider A being Ordinal such that
A4:
S2[A]
and
A5:
for B being Ordinal st S2[B] holds
A c= B
from ORDINAL1:sch 1(A3);
consider X being set such that
A6:
( A = the_rank_of X & X in W & not A in W )
by A4;
A7:
( On W = card W & X c= W )
by A1, A6, Th10, ORDINAL1:def 2;
A8:
On W = A
A9:
card X in card W
by A2, A6, Th1;
defpred S3[ set ] means ex Y being set st
( Y in X & $1 = the_rank_of Y );
consider LL being set such that
A10:
for x being set holds
( x in LL iff ( x in On W & S3[x] ) )
from XBOOLE_0:sch 1();
A11:
LL c= On W
then reconsider ULL = union LL as Ordinal by ORDINAL1:31;
consider f being Function such that
A14:
( dom f = X & ( for x being set st x in X holds
f . x = H1(x) ) )
from FUNCT_1:sch 3();
LL c= rng f
then
card LL c= card X
by A14, CARD_1:28;
then
( card LL <> card W & On W c= W )
by A9, ORDINAL1:22, ORDINAL2:9;
then
( not LL,W are_equipotent & LL c= W )
by A11, CARD_1:21, XBOOLE_1:1;
then
LL in W
by A1, CLASSES1:def 2;
then A16:
Funcs LL,W c= W
by A1, Th23;
A17:
ULL = Union (id LL)
consider ff being Cardinal-Function such that
A18:
( dom ff = LL & ( for x being set st x in LL holds
ff . x = H2(x) ) )
from CARD_3:sch 1();
A19:
( dom (id LL) = LL & dom (Card (id LL)) = dom (id LL) )
by CARD_3:def 2, RELAT_1:71;
then
Sum (Card (id LL)) in Product ff
by A18, A19, CARD_3:56;
then A20:
card ULL in Product ff
by A17, CARD_3:54, ORDINAL1:22;
product ff c= Funcs LL,W
proof
let x be
set ;
:: according to TARSKI:def 3 :: thesis: ( not x in product ff or x in Funcs LL,W )
assume
x in product ff
;
:: thesis: x in Funcs LL,W
then consider g being
Function such that A21:
(
x = g &
dom g = dom ff & ( for
x being
set st
x in dom ff holds
g . x in ff . x ) )
by CARD_3:def 5;
rng g c= W
proof
let y be
set ;
:: according to TARSKI:def 3 :: thesis: ( not y in rng g or y in W )
assume
y in rng g
;
:: thesis: y in W
then consider x being
set such that A22:
(
x in dom g &
y = g . x )
by FUNCT_1:def 5;
A23:
(
y in ff . x &
ff . x = ff . x &
x = x &
ff . x = card (bool x) &
x in On W )
by A11, A18, A21, A22;
x in W
by A11, A18, A21, A22, ORDINAL1:def 10;
then
bool x in W
by A1, CLASSES1:def 2;
then
card (bool x) in W
by A1, Th12;
then
card (bool x) c= W
by A1, Th6;
hence
y in W
by A23;
:: thesis: verum
end;
hence
x in Funcs LL,
W
by A18, A21, FUNCT_2:def 2;
:: thesis: verum
end;
then
( product ff c= W & card (product ff) = Product ff )
by A16, CARD_3:def 8, XBOOLE_1:1;
then A24:
Product ff c= card W
by CARD_1:27;
On W c= ULL
then
( card (On W) c= card ULL & On W = card W & card W = card (card W) )
by A1, Th10, CARD_1:27;
hence
contradiction
by A20, A24, CARD_1:14; :: thesis: verum