let X be set ; :: thesis: for L being non empty complete continuous Poset
for f being Function of FixedUltraFilters X,the carrier of L
for h being CLHomomorphism of InclPoset (Filt (BoolePoset X)),L st h | (FixedUltraFilters X) = f holds
h = f -extension_to_hom

let L be non empty complete continuous Poset; :: thesis: for f being Function of FixedUltraFilters X,the carrier of L
for h being CLHomomorphism of InclPoset (Filt (BoolePoset X)),L st h | (FixedUltraFilters X) = f holds
h = f -extension_to_hom

let f be Function of FixedUltraFilters X,the carrier of L; :: thesis: for h being CLHomomorphism of InclPoset (Filt (BoolePoset X)),L st h | (FixedUltraFilters X) = f holds
h = f -extension_to_hom

let h be CLHomomorphism of InclPoset (Filt (BoolePoset X)),L; :: thesis: ( h | (FixedUltraFilters X) = f implies h = f -extension_to_hom )
assume A1: h | (FixedUltraFilters X) = f ; :: thesis: h = f -extension_to_hom
set BP = BoolePoset X;
set IP = InclPoset (Filt (BoolePoset X));
set cIP = the carrier of (InclPoset (Filt (BoolePoset X)));
set cL = the carrier of L;
set F = f -extension_to_hom ;
A2: InclPoset (Filt (BoolePoset X)) = RelStr(# (Filt (BoolePoset X)),(RelIncl (Filt (BoolePoset X))) #) by YELLOW_1:def 1;
A3: the carrier of (BoolePoset X) = the carrier of (LattPOSet (BooleLatt X)) by YELLOW_1:def 2
.= bool X by LATTICE3:def 1 ;
reconsider h' = h as Function of the carrier of (InclPoset (Filt (BoolePoset X))),the carrier of L ;
reconsider F' = f -extension_to_hom as Function of the carrier of (InclPoset (Filt (BoolePoset X))),the carrier of L ;
now
let Fi be Element of the carrier of (InclPoset (Filt (BoolePoset X))); :: thesis: h' . Fi = F' . Fi
Fi in Filt (BoolePoset X) by A2;
then consider FF being Filter of (BoolePoset X) such that
A4: Fi = FF ;
A5: FF = "\/" { ("/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,(InclPoset (Filt (BoolePoset X)))
)
where Y is Subset of X : Y in FF
}
,(InclPoset (Filt (BoolePoset X))) by Th11;
set Xs = { ("/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,(InclPoset (Filt (BoolePoset X)))
)
where Y is Subset of X : Y in FF
}
;
A6: ( h is infs-preserving & h is directed-sups-preserving ) by WAYBEL16:def 1;
A7: { ("/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,(InclPoset (Filt (BoolePoset X)))) where Y is Subset of X : Y in FF } c= the carrier of (InclPoset (Filt (BoolePoset X)))
proof
let p be set ; :: according to TARSKI:def 3 :: thesis: ( not p in { ("/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,(InclPoset (Filt (BoolePoset X)))
)
where Y is Subset of X : Y in FF
}
or p in the carrier of (InclPoset (Filt (BoolePoset X))) )

assume p in { ("/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,(InclPoset (Filt (BoolePoset X)))
)
where Y is Subset of X : Y in FF
}
; :: thesis: p in the carrier of (InclPoset (Filt (BoolePoset X)))
then consider YY being Subset of X such that
A8: p = "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in YY )
}
,(InclPoset (Filt (BoolePoset X))) and
YY in FF ;
thus p in the carrier of (InclPoset (Filt (BoolePoset X))) by A8; :: thesis: verum
end;
now
consider YY being set such that
A9: YY in FF by XBOOLE_0:def 1;
"/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in YY )
}
,(InclPoset (Filt (BoolePoset X))) in { ("/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,(InclPoset (Filt (BoolePoset X)))
)
where Y is Subset of X : Y in FF
}
by A3, A9;
hence not { ("/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,(InclPoset (Filt (BoolePoset X)))) where Y is Subset of X : Y in FF } is empty ; :: thesis: verum
end;
then reconsider Xs = { ("/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,(InclPoset (Filt (BoolePoset X)))
)
where Y is Subset of X : Y in FF
}
as non empty Subset of (InclPoset (Filt (BoolePoset X))) by A7;
Xs is directed
proof
let a, b be Element of (InclPoset (Filt (BoolePoset X))); :: according to WAYBEL_0:def 1 :: thesis: ( not a in Xs or not b in Xs or ex b1 being Element of the carrier of (InclPoset (Filt (BoolePoset X))) st
( b1 in Xs & a <= b1 & b <= b1 ) )

assume A10: ( a in Xs & b in Xs ) ; :: thesis: ex b1 being Element of the carrier of (InclPoset (Filt (BoolePoset X))) st
( b1 in Xs & a <= b1 & b <= b1 )

then consider Ya being Subset of X such that
A11: a = "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Ya )
}
,(InclPoset (Filt (BoolePoset X))) and
A12: Ya in FF ;
reconsider Ya' = Ya as Element of FF by A12;
consider Yb being Subset of X such that
A13: b = "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yb )
}
,(InclPoset (Filt (BoolePoset X))) and
A14: Yb in FF by A10;
reconsider Yb' = Yb as Element of FF by A14;
set Xsa = { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Ya )
}
;
set Xsb = { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yb )
}
;
per cases ( { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Ya ) } is empty or { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yb )
}
is empty or ( not { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Ya )
}
is empty & not { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yb )
}
is empty ) ) ;
suppose { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Ya ) } is empty ; :: thesis: ex b1 being Element of the carrier of (InclPoset (Filt (BoolePoset X))) st
( b1 in Xs & a <= b1 & b <= b1 )

then A15: "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Ya )
}
,(InclPoset (Filt (BoolePoset X))) = Top (InclPoset (Filt (BoolePoset X))) ;
take a ; :: thesis: ( a in Xs & a <= a & b <= a )
thus a in Xs by A10; :: thesis: ( a <= a & b <= a )
thus a <= a ; :: thesis: b <= a
thus b <= a by A11, A15, YELLOW_0:45; :: thesis: verum
end;
suppose { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yb ) } is empty ; :: thesis: ex b1 being Element of the carrier of (InclPoset (Filt (BoolePoset X))) st
( b1 in Xs & a <= b1 & b <= b1 )

then A16: "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yb )
}
,(InclPoset (Filt (BoolePoset X))) = Top (InclPoset (Filt (BoolePoset X))) ;
take b ; :: thesis: ( b in Xs & a <= b & b <= b )
thus b in Xs by A10; :: thesis: ( a <= b & b <= b )
thus a <= b by A13, A16, YELLOW_0:45; :: thesis: b <= b
thus b <= b ; :: thesis: verum
end;
suppose A17: ( not { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Ya ) } is empty & not { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yb )
}
is empty ) ; :: thesis: ex b1 being Element of the carrier of (InclPoset (Filt (BoolePoset X))) st
( b1 in Xs & a <= b1 & b <= b1 )

{ (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Ya ) } c= the carrier of (InclPoset (Filt (BoolePoset X)))
proof
let r be set ; :: according to TARSKI:def 3 :: thesis: ( not r in { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Ya )
}
or r in the carrier of (InclPoset (Filt (BoolePoset X))) )

assume r in { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Ya )
}
; :: thesis: r in the carrier of (InclPoset (Filt (BoolePoset X)))
then consider xz being Element of (BoolePoset X) such that
A18: r = uparrow xz and
ex z being Element of X st
( xz = {z} & z in Ya ) ;
thus r in the carrier of (InclPoset (Filt (BoolePoset X))) by A2, A18; :: thesis: verum
end;
then reconsider Xsa = { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Ya )
}
as non empty Subset of (InclPoset (Filt (BoolePoset X))) by A17;
A19: "/\" Xsa,(InclPoset (Filt (BoolePoset X))) = meet Xsa by WAYBEL16:10;
{ (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yb ) } c= the carrier of (InclPoset (Filt (BoolePoset X)))
proof
let r be set ; :: according to TARSKI:def 3 :: thesis: ( not r in { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yb )
}
or r in the carrier of (InclPoset (Filt (BoolePoset X))) )

assume r in { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yb )
}
; :: thesis: r in the carrier of (InclPoset (Filt (BoolePoset X)))
then consider xz being Element of (BoolePoset X) such that
A20: r = uparrow xz and
ex z being Element of X st
( xz = {z} & z in Yb ) ;
thus r in the carrier of (InclPoset (Filt (BoolePoset X))) by A2, A20; :: thesis: verum
end;
then reconsider Xsb = { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yb )
}
as non empty Subset of (InclPoset (Filt (BoolePoset X))) by A17;
A21: "/\" Xsb,(InclPoset (Filt (BoolePoset X))) = meet Xsb by WAYBEL16:10;
consider Yab being Element of (BoolePoset X) such that
A22: Yab in FF and
A23: Yab <= Ya' and
A24: Yab <= Yb' by WAYBEL_0:def 2;
reconsider Yab = Yab as Element of FF by A22;
set c = "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X)));
set Xsc = { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
;
thus ex b1 being Element of the carrier of (InclPoset (Filt (BoolePoset X))) st
( b1 in Xs & a <= b1 & b <= b1 ) :: thesis: verum
proof
per cases ( { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab ) } is empty or not { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
is empty ) ;
suppose { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab ) } is empty ; :: thesis: ex b1 being Element of the carrier of (InclPoset (Filt (BoolePoset X))) st
( b1 in Xs & a <= b1 & b <= b1 )

then A25: "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) = Top (InclPoset (Filt (BoolePoset X))) ;
take "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) ; :: thesis: ( "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) in Xs & a <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) & b <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) )

thus "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) in Xs by A3; :: thesis: ( a <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) & b <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) )

thus a <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) by A25, YELLOW_0:45; :: thesis: b <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X)))

thus b <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) by A25, YELLOW_0:45; :: thesis: verum
end;
suppose A26: not { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab ) } is empty ; :: thesis: ex b1 being Element of the carrier of (InclPoset (Filt (BoolePoset X))) st
( b1 in Xs & a <= b1 & b <= b1 )

{ (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab ) } c= the carrier of (InclPoset (Filt (BoolePoset X)))
proof
let r be set ; :: according to TARSKI:def 3 :: thesis: ( not r in { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
or r in the carrier of (InclPoset (Filt (BoolePoset X))) )

assume r in { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
; :: thesis: r in the carrier of (InclPoset (Filt (BoolePoset X)))
then consider xz being Element of (BoolePoset X) such that
A27: r = uparrow xz and
ex z being Element of X st
( xz = {z} & z in Yab ) ;
thus r in the carrier of (InclPoset (Filt (BoolePoset X))) by A2, A27; :: thesis: verum
end;
then reconsider Xsc = { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
as non empty Subset of (InclPoset (Filt (BoolePoset X))) by A26;
A28: "/\" Xsc,(InclPoset (Filt (BoolePoset X))) = meet Xsc by WAYBEL16:10;
take "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) ; :: thesis: ( "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) in Xs & a <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) & b <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) )

thus "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) in Xs by A3; :: thesis: ( a <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) & b <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) )

a c= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X)))
proof
let d be set ; :: according to TARSKI:def 3 :: thesis: ( not d in a or d in "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) )

assume A29: d in a ; :: thesis: d in "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X)))

Xsc c= Xsa
proof
let r be set ; :: according to TARSKI:def 3 :: thesis: ( not r in Xsc or r in Xsa )
assume r in Xsc ; :: thesis: r in Xsa
then consider xz being Element of (BoolePoset X) such that
A30: r = uparrow xz and
A31: ex z being Element of X st
( xz = {z} & z in Yab ) ;
consider zz being Element of X such that
A32: xz = {zz} and
A33: zz in Yab by A31;
Yab c= Ya by A23, YELLOW_1:2;
hence r in Xsa by A30, A32, A33; :: thesis: verum
end;
then meet Xsa c= meet Xsc by SETFAM_1:7;
hence d in "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) by A11, A19, A28, A29; :: thesis: verum
end;
hence a <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) by YELLOW_1:3; :: thesis: b <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X)))

b c= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X)))
proof
let d be set ; :: according to TARSKI:def 3 :: thesis: ( not d in b or d in "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) )

assume A34: d in b ; :: thesis: d in "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X)))

Xsc c= Xsb
proof
let r be set ; :: according to TARSKI:def 3 :: thesis: ( not r in Xsc or r in Xsb )
assume r in Xsc ; :: thesis: r in Xsb
then consider xz being Element of (BoolePoset X) such that
A35: r = uparrow xz and
A36: ex z being Element of X st
( xz = {z} & z in Yab ) ;
consider zz being Element of X such that
A37: xz = {zz} and
A38: zz in Yab by A36;
Yab c= Yb by A24, YELLOW_1:2;
hence r in Xsb by A35, A37, A38; :: thesis: verum
end;
then meet Xsb c= meet Xsc by SETFAM_1:7;
hence d in "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) by A13, A21, A28, A34; :: thesis: verum
end;
hence b <= "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Yab )
}
,(InclPoset (Filt (BoolePoset X))) by YELLOW_1:3; :: thesis: verum
end;
end;
end;
end;
end;
end;
then A39: h preserves_sup_of Xs by A6, WAYBEL_0:def 37;
A40: ex_sup_of Xs, InclPoset (Filt (BoolePoset X)) by YELLOW_0:17;
set Xsf = { ("/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L
)
where Y is Subset of X : Y in FF
}
;
set FUF = FixedUltraFilters X;
now
let s be set ; :: thesis: ( ( s in h .: Xs implies s in { ("/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L
)
where Y is Subset of X : Y in FF
}
) & ( s in { ("/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L
)
where Y is Subset of X : Y in FF
}
implies s in h .: Xs ) )

hereby :: thesis: ( s in { ("/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L
)
where Y is Subset of X : Y in FF
}
implies s in h .: Xs )
assume s in h .: Xs ; :: thesis: s in { ("/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L
)
where Y is Subset of X : Y in FF
}

then consider t being set such that
t in the carrier of (InclPoset (Filt (BoolePoset X))) and
A41: t in Xs and
A42: s = h . t by FUNCT_2:115;
consider Y being Subset of X such that
A43: t = "/\" { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,(InclPoset (Filt (BoolePoset X))) and
A44: Y in FF by A41;
set Xsi = { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
;
{ (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y ) } c= the carrier of (InclPoset (Filt (BoolePoset X)))
proof
let r be set ; :: according to TARSKI:def 3 :: thesis: ( not r in { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
or r in the carrier of (InclPoset (Filt (BoolePoset X))) )

assume r in { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
; :: thesis: r in the carrier of (InclPoset (Filt (BoolePoset X)))
then consider xz being Element of (BoolePoset X) such that
A45: r = uparrow xz and
ex z being Element of X st
( xz = {z} & z in Y ) ;
thus r in the carrier of (InclPoset (Filt (BoolePoset X))) by A2, A45; :: thesis: verum
end;
then reconsider Xsi = { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
as Subset of (InclPoset (Filt (BoolePoset X))) ;
A46: h preserves_inf_of Xsi by A6, WAYBEL_0:def 32;
ex_inf_of Xsi, InclPoset (Filt (BoolePoset X)) by YELLOW_0:17;
then A47: inf (h .: Xsi) = h . (inf Xsi) by A46, WAYBEL_0:def 30;
set Xsif = { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
;
now
let u be set ; :: thesis: ( ( u in h .: Xsi implies u in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
) & ( u in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
implies u in h .: Xsi ) )

hereby :: thesis: ( u in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
implies u in h .: Xsi )
assume u in h .: Xsi ; :: thesis: u in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}

then consider v being set such that
v in the carrier of (InclPoset (Filt (BoolePoset X))) and
A48: v in Xsi and
A49: u = h . v by FUNCT_2:115;
consider x being Element of (BoolePoset X) such that
A50: v = uparrow x and
A51: ex z being Element of X st
( x = {z} & z in Y ) by A48;
consider z being Element of X such that
A52: ( x = {z} & z in Y ) by A51;
v in FixedUltraFilters X by A50, A52;
then h . v = f . v by A1, FUNCT_1:72;
hence u in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
by A49, A50, A51; :: thesis: verum
end;
assume u in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
; :: thesis: u in h .: Xsi
then consider x being Element of (BoolePoset X) such that
A53: u = f . (uparrow x) and
A54: ex z being Element of X st
( x = {z} & z in Y ) ;
consider z being Element of X such that
A55: ( x = {z} & z in Y ) by A54;
A56: uparrow x in Xsi by A54;
uparrow x in FixedUltraFilters X by A55;
then h . (uparrow x) = f . (uparrow x) by A1, FUNCT_1:72;
hence u in h .: Xsi by A53, A56, FUNCT_2:43; :: thesis: verum
end;
then h .: Xsi = { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
by TARSKI:2;
hence s in { ("/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L
)
where Y is Subset of X : Y in FF
}
by A42, A43, A44, A47; :: thesis: verum
end;
assume s in { ("/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L
)
where Y is Subset of X : Y in FF
}
; :: thesis: s in h .: Xs
then consider Y being Subset of X such that
A57: s = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L and
A58: Y in FF ;
set Xsi = { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
;
{ (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y ) } c= the carrier of (InclPoset (Filt (BoolePoset X)))
proof
let r be set ; :: according to TARSKI:def 3 :: thesis: ( not r in { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
or r in the carrier of (InclPoset (Filt (BoolePoset X))) )

assume r in { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
; :: thesis: r in the carrier of (InclPoset (Filt (BoolePoset X)))
then consider xz being Element of (BoolePoset X) such that
A59: r = uparrow xz and
ex z being Element of X st
( xz = {z} & z in Y ) ;
thus r in the carrier of (InclPoset (Filt (BoolePoset X))) by A2, A59; :: thesis: verum
end;
then reconsider Xsi = { (uparrow x) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
as Subset of (InclPoset (Filt (BoolePoset X))) ;
A60: h preserves_inf_of Xsi by A6, WAYBEL_0:def 32;
ex_inf_of Xsi, InclPoset (Filt (BoolePoset X)) by YELLOW_0:17;
then A61: inf (h .: Xsi) = h . (inf Xsi) by A60, WAYBEL_0:def 30;
set Xsif = { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
;
A62: inf Xsi in Xs by A58;
now
let u be set ; :: thesis: ( ( u in h .: Xsi implies u in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
) & ( u in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
implies u in h .: Xsi ) )

hereby :: thesis: ( u in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
implies u in h .: Xsi )
assume u in h .: Xsi ; :: thesis: u in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}

then consider v being set such that
v in the carrier of (InclPoset (Filt (BoolePoset X))) and
A63: v in Xsi and
A64: u = h . v by FUNCT_2:115;
consider x being Element of (BoolePoset X) such that
A65: v = uparrow x and
A66: ex z being Element of X st
( x = {z} & z in Y ) by A63;
consider z being Element of X such that
A67: ( x = {z} & z in Y ) by A66;
v in FixedUltraFilters X by A65, A67;
then h . v = f . v by A1, FUNCT_1:72;
hence u in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
by A64, A65, A66; :: thesis: verum
end;
assume u in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
; :: thesis: u in h .: Xsi
then consider x being Element of (BoolePoset X) such that
A68: u = f . (uparrow x) and
A69: ex z being Element of X st
( x = {z} & z in Y ) ;
consider z being Element of X such that
A70: ( x = {z} & z in Y ) by A69;
A71: uparrow x in Xsi by A69;
uparrow x in FixedUltraFilters X by A70;
then h . (uparrow x) = f . (uparrow x) by A1, FUNCT_1:72;
hence u in h .: Xsi by A68, A71, FUNCT_2:43; :: thesis: verum
end;
then h .: Xsi = { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
by TARSKI:2;
hence s in h .: Xs by A57, A61, A62, FUNCT_2:43; :: thesis: verum
end;
then A72: h .: Xs = { ("/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L
)
where Y is Subset of X : Y in FF
}
by TARSKI:2;
thus h' . Fi = sup (h .: Xs) by A4, A5, A39, A40, WAYBEL_0:def 31
.= F' . Fi by A4, A72, Def3 ; :: thesis: verum
end;
hence h = f -extension_to_hom by FUNCT_2:113; :: thesis: verum