set BP = BoolePoset X;
set IP = InclPoset (Filt (BoolePoset X));
set F = f -extension_to_hom ;
set cIP = the carrier of (InclPoset (Filt (BoolePoset X)));
set cL = the carrier of L;
set FUF = FixedUltraFilters X;
A1: InclPoset (Filt (BoolePoset X)) = RelStr(# (Filt (BoolePoset X)),(RelIncl (Filt (BoolePoset X))) #) by YELLOW_1:def 1;
A2: BoolePoset X = InclPoset (bool X) by YELLOW_1:4;
A3: InclPoset (bool X) = RelStr(# (bool X),(RelIncl (bool X)) #) by YELLOW_1:def 1;
then A4: the carrier of (BoolePoset X) = bool X by YELLOW_1:4;
let Fs be Subset of (InclPoset (Filt (BoolePoset X))); :: according to WAYBEL_0:def 32 :: thesis: f -extension_to_hom preserves_inf_of Fs
assume ex_inf_of Fs, InclPoset (Filt (BoolePoset X)) ; :: according to WAYBEL_0:def 30 :: thesis: ( ex_inf_of (f -extension_to_hom ) .: Fs,L & "/\" ((f -extension_to_hom ) .: Fs),L = (f -extension_to_hom ) . ("/\" Fs,(InclPoset (Filt (BoolePoset X)))) )
thus ex_inf_of (f -extension_to_hom ) .: Fs,L by YELLOW_0:17; :: thesis: "/\" ((f -extension_to_hom ) .: Fs),L = (f -extension_to_hom ) . ("/\" Fs,(InclPoset (Filt (BoolePoset X))))
per cases ( Fs is empty or not Fs is empty ) ;
suppose A5: Fs is empty ; :: thesis: "/\" ((f -extension_to_hom ) .: Fs),L = (f -extension_to_hom ) . ("/\" Fs,(InclPoset (Filt (BoolePoset X))))
end;
suppose not Fs is empty ; :: thesis: "/\" ((f -extension_to_hom ) .: Fs),L = (f -extension_to_hom ) . ("/\" Fs,(InclPoset (Filt (BoolePoset X))))
then reconsider Fs' = Fs as non empty Subset of (InclPoset (Filt (BoolePoset X))) ;
not {} in Fs' ;
then Fs' is with_non-empty_elements by SETFAM_1:def 9;
then reconsider K = id Fs' as V8() ManySortedSet of ;
defpred S1[ set , set , set ] means X = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in L )
}
,L;
A7: for i being set st i in Fs' holds
for s being set st s in K . i holds
ex y being set st
( y in (Fs' --> the carrier of L) . i & S1[y,s,i] )
proof
let i be set ; :: thesis: ( i in Fs' implies for s being set st s in K . i holds
ex y being set st
( y in (Fs' --> the carrier of L) . i & S1[y,s,i] ) )

assume A8: i in Fs' ; :: thesis: for s being set st s in K . i holds
ex y being set st
( y in (Fs' --> the carrier of L) . i & S1[y,s,i] )

let s be set ; :: thesis: ( s in K . i implies ex y being set st
( y in (Fs' --> the carrier of L) . i & S1[y,s,i] ) )

assume s in K . i ; :: thesis: ex y being set st
( y in (Fs' --> the carrier of L) . i & S1[y,s,i] )

take y = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s )
}
,L; :: thesis: ( y in (Fs' --> the carrier of L) . i & S1[y,s,i] )
y in the carrier of L ;
hence y in (Fs' --> the carrier of L) . i by A8, FUNCOP_1:13; :: thesis: S1[y,s,i]
thus S1[y,s,i] ; :: thesis: verum
end;
consider FD being ManySortedFunction of K,Fs' --> the carrier of L such that
A9: for i being set st i in Fs' holds
ex g being Function of (K . i),((Fs' --> the carrier of L) . i) st
( g = FD . i & ( for s being set st s in K . i holds
S1[g . s,s,i] ) ) from MSSUBFAM:sch 1(A7);
A10: dom FD = Fs' by PARTFUN1:def 4;
deffunc H1( Element of Fs') -> set = { ("/\" { (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 X
}
;
defpred S2[ Element of Fs'] means rng (FD . X) = H1(X);
A11: for s being Element of Fs' holds S2[s]
proof
let s be Element of Fs'; :: thesis: S2[s]
now
let t be set ; :: thesis: ( ( t in rng (FD . s) implies t in H1(s) ) & ( t in H1(s) implies t in rng (FD . s) ) )
hereby :: thesis: ( t in H1(s) implies t in rng (FD . s) )
assume t in rng (FD . s) ; :: thesis: t in H1(s)
then consider u being set such that
A12: u in dom (FD . s) and
A13: t = (FD . s) . u by FUNCT_1:def 5;
A14: dom (FD . s) = K . s by FUNCT_2:def 1;
consider g being Function of (K . s),((Fs' --> the carrier of L) . s) such that
A15: g = FD . s and
A16: for u being set st u in K . s holds
S1[g . u,u,s] by A9;
A17: g . u = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in u )
}
,L by A12, A16;
A18: K . s = s by FUNCT_1:35;
s in the carrier of (InclPoset (Filt (BoolePoset X))) ;
then consider FF being Filter of (BoolePoset X) such that
A19: s = FF by A1;
reconsider u = u as Subset of X by A3, A12, A14, A18, A19, YELLOW_1:4;
u in s by A12, A14, FUNCT_1:35;
hence t in H1(s) by A13, A15, A17; :: thesis: verum
end;
assume t in H1(s) ; :: thesis: t in rng (FD . s)
then consider Y being Subset of X such that
A20: t = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L and
A21: Y in s ;
A22: dom (FD . s) = K . s by FUNCT_2:def 1;
A23: K . s = s by FUNCT_1:35;
A24: Y in dom (FD . s) by A21, A22, FUNCT_1:35;
consider g being Function of (K . s),((Fs' --> the carrier of L) . s) such that
A25: g = FD . s and
A26: for u being set st u in K . s holds
S1[g . u,u,s] by A9;
g . Y = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L by A21, A23, A26;
hence t in rng (FD . s) by A20, A24, A25, FUNCT_1:def 5; :: thesis: verum
end;
hence S2[s] by TARSKI:2; :: thesis: verum
end;
reconsider FD = FD as DoubleIndexedSet of K,L ;
now
let r be set ; :: thesis: ( ( r in (f -extension_to_hom ) .: Fs implies r in rng (Sups ) ) & ( r in rng (Sups ) implies r in (f -extension_to_hom ) .: Fs ) )
hereby :: thesis: ( r in rng (Sups ) implies r in (f -extension_to_hom ) .: Fs )
assume r in (f -extension_to_hom ) .: Fs ; :: thesis: r in rng (Sups )
then consider s being set such that
A27: s in the carrier of (InclPoset (Filt (BoolePoset X))) and
A28: s in Fs and
A29: (f -extension_to_hom ) . s = r by FUNCT_2:115;
reconsider s' = s as Element of the carrier of (InclPoset (Filt (BoolePoset X))) by A27;
A30: (f -extension_to_hom ) . s' = "\/" { ("/\" { (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 s'
}
,L by Def3;
reconsider s = s as Element of Fs' by A28;
S2[s] by A11;
then r = Sup by A29, A30, YELLOW_2:def 5;
hence r in rng (Sups ) by WAYBEL_5:14; :: thesis: verum
end;
assume r in rng (Sups ) ; :: thesis: r in (f -extension_to_hom ) .: Fs
then consider s being Element of Fs' such that
A31: r = Sup by WAYBEL_5:14;
S2[s] by A11;
then (f -extension_to_hom ) . s = "\/" (rng (FD . s)),L by Def3
.= Sup by YELLOW_2:def 5 ;
hence r in (f -extension_to_hom ) .: Fs by A31, FUNCT_2:43; :: thesis: verum
end;
then (f -extension_to_hom ) .: Fs = rng (Sups ) by TARSKI:2;
then A32: inf ((f -extension_to_hom ) .: Fs) = Inf by YELLOW_2:def 6;
for j being Element of Fs' holds rng (FD . j) is directed
proof
let j be Element of Fs'; :: thesis: rng (FD . j) is directed
let k, m be Element of L; :: according to WAYBEL_0:def 1 :: thesis: ( not k in rng (FD . j) or not m in rng (FD . j) or ex b1 being Element of the carrier of L st
( b1 in rng (FD . j) & k <= b1 & m <= b1 ) )

assume A33: ( k in rng (FD . j) & m in rng (FD . j) ) ; :: thesis: ex b1 being Element of the carrier of L st
( b1 in rng (FD . j) & k <= b1 & m <= b1 )

then consider kd being set such that
A34: kd in dom (FD . j) and
A35: (FD . j) . kd = k by FUNCT_1:def 5;
consider md being set such that
A36: md in dom (FD . j) and
A37: (FD . j) . md = m by A33, FUNCT_1:def 5;
A38: dom (FD . j) = K . j by FUNCT_2:def 1;
A39: K . j = j by FUNCT_1:35;
j in the carrier of (InclPoset (Filt (BoolePoset X))) ;
then consider FF being Filter of (BoolePoset X) such that
A40: j = FF by A1;
reconsider kd = kd as Element of (BoolePoset X) by A34, A38, A39, A40;
reconsider md = md as Element of (BoolePoset X) by A36, A38, A39, A40;
consider nd being Element of (BoolePoset X) such that
A41: ( nd in FF & nd <= kd & nd <= md ) by A34, A36, A39, A40, WAYBEL_0:def 2;
A42: rng (FD . j) = H1(j) by A11;
set n = (FD . j) . nd;
(FD . j) . nd in rng (FD . j) by A38, A39, A40, A41, FUNCT_1:def 5;
then consider Y being Subset of X such that
A43: (FD . j) . nd = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L and
Y in j by A42;
reconsider n = (FD . j) . nd as Element of L by A43;
take n ; :: thesis: ( n in rng (FD . j) & k <= n & m <= n )
thus n in rng (FD . j) by A38, A39, A40, A41, FUNCT_1:def 5; :: thesis: ( k <= n & m <= n )
consider g being Function of (K . j),((Fs' --> the carrier of L) . j) such that
A44: g = FD . j and
A45: for u being set st u in K . j holds
S1[g . u,u,j] by A9;
set kds = { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in kd )
}
;
A46: g . kd = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in kd )
}
,L by A34, A45;
set nds = { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in nd )
}
;
A47: g . nd = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in nd )
}
,L by A39, A40, A41, A45;
A48: nd c= kd by A41, YELLOW_1:2;
A49: ex_inf_of { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in kd )
}
,L by YELLOW_0:17;
A50: ex_inf_of { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in nd )
}
,L by YELLOW_0:17;
{ (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in nd ) } c= { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in kd )
}
proof
let w be set ; :: according to TARSKI:def 3 :: thesis: ( not w in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in nd )
}
or w in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in kd )
}
)

assume w in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in nd )
}
; :: thesis: w in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in kd )
}

then consider x being Element of (BoolePoset X) such that
A51: w = f . (uparrow x) and
A52: ex z being Element of X st
( x = {z} & z in nd ) ;
consider z being Element of X such that
A53: ( x = {z} & z in nd ) by A52;
thus w in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in kd )
}
by A48, A51, A53; :: thesis: verum
end;
hence k <= n by A35, A44, A46, A47, A49, A50, YELLOW_0:35; :: thesis: m <= n
set mds = { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in md )
}
;
A54: g . md = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in md )
}
,L by A36, A45;
A55: nd c= md by A41, YELLOW_1:2;
A56: ex_inf_of { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in md )
}
,L by YELLOW_0:17;
{ (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in nd ) } c= { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in md )
}
proof
let w be set ; :: according to TARSKI:def 3 :: thesis: ( not w in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in nd )
}
or w in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in md )
}
)

assume w in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in nd )
}
; :: thesis: w in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in md )
}

then consider x being Element of (BoolePoset X) such that
A57: w = f . (uparrow x) and
A58: ex z being Element of X st
( x = {z} & z in nd ) ;
consider z being Element of X such that
A59: ( x = {z} & z in nd ) by A58;
thus w in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in md )
}
by A55, A57, A59; :: thesis: verum
end;
hence m <= n by A37, A44, A47, A50, A54, A56, YELLOW_0:35; :: thesis: verum
end;
then A60: Inf = Sup by WAYBEL_5:19
.= "\/" (rng (Infs )),L by YELLOW_2:def 5 ;
meet Fs' is Filter of (BoolePoset X) by WAYBEL16:9;
then meet Fs' in Filt (BoolePoset X) ;
then reconsider mFs = meet Fs' as Element of the carrier of (InclPoset (Filt (BoolePoset X))) by A1;
A61: inf Fs' = meet Fs' by WAYBEL16:10;
set smFs = { ("/\" { (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 mFs
}
;
A62: (f -extension_to_hom ) . (meet Fs') = "\/" { ("/\" { (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 mFs
}
,L by Def3;
now
let r be set ; :: thesis: ( ( r in rng (Infs ) implies r 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 mFs
}
) & ( r 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 mFs
}
implies r in rng (Infs ) ) )

reconsider pdFD = product (doms FD) as non empty functional set ;
reconsider dFFD = (product (doms FD)) --> Fs' as ManySortedSet of ;
reconsider FFD = Frege FD as DoubleIndexedSet of dFFD,L ;
A63: dom FFD = pdFD by PARTFUN1:def 4;
deffunc H2( Element of pdFD) -> set = { ("/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in X . u )
}
,L
)
where u is Element of Fs' : u in dom (FFD . X)
}
;
A64: now
let s be Element of pdFD; :: thesis: rng (FFD . s) = H2(s)
A65: dom FD = dom (FFD . s) by A63, WAYBEL_5:8;
now
let t be set ; :: thesis: ( ( t in rng (FFD . s) implies t in H2(s) ) & ( t in H2(s) implies t in rng (FFD . s) ) )
hereby :: thesis: ( t in H2(s) implies t in rng (FFD . s) )
assume t in rng (FFD . s) ; :: thesis: t in H2(s)
then consider u being set such that
A66: u in dom (FFD . s) and
A67: t = (FFD . s) . u by FUNCT_1:def 5;
A68: (FFD . s) . u = (FD . u) . (s . u) by A63, A65, A66, WAYBEL_5:9;
reconsider u = u as Element of Fs' by A65, A66, PARTFUN1:def 4;
consider g being Function of (K . u),((Fs' --> the carrier of L) . u) such that
A69: g = FD . u and
A70: for v being set st v in K . u holds
S1[g . v,v,u] by A9;
dom (FD . u) = K . u by FUNCT_2:def 1;
then s . u in K . u by A10, A63, WAYBEL_5:9;
then g . (s . u) = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
,L by A70;
hence t in H2(s) by A66, A67, A68, A69; :: thesis: verum
end;
assume t in H2(s) ; :: thesis: t in rng (FFD . s)
then consider u being Element of Fs' such that
A71: t = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
,L and
A72: u in dom (FFD . s) ;
reconsider u = u as Element of Fs' ;
consider g being Function of (K . u),((Fs' --> the carrier of L) . u) such that
A73: g = FD . u and
A74: for v being set st v in K . u holds
S1[g . v,v,u] by A9;
dom (FD . u) = K . u by FUNCT_2:def 1;
then s . u in K . u by A10, A63, WAYBEL_5:9;
then g . (s . u) = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
,L by A74;
hence t in rng (FFD . s) by A63, A65, A71, A72, A73, WAYBEL_5:9; :: thesis: verum
end;
hence rng (FFD . s) = H2(s) by TARSKI:2; :: thesis: verum
end;
hereby :: thesis: ( r 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 mFs
}
implies r in rng (Infs ) )
assume r in rng (Infs ) ; :: thesis: r 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 mFs
}

then consider s being Element of pdFD such that
A75: r = Inf by WAYBEL_5:14;
A76: dom FD = dom (FFD . s) by A63, WAYBEL_5:8;
A77: dom s = dom FD by A63, WAYBEL_5:8;
union (rng s) c= X
proof
let t be set ; :: according to TARSKI:def 3 :: thesis: ( not t in union (rng s) or t in X )
assume t in union (rng s) ; :: thesis: t in X
then consider te being set such that
A78: ( t in te & te in rng s ) by TARSKI:def 4;
consider u being set such that
A79: ( u in dom s & te = s . u ) by A78, FUNCT_1:def 5;
FD . u is Function of (K . u),the carrier of L by A10, A77, A79, WAYBEL_5:6;
then dom (FD . u) = K . u by FUNCT_2:def 1
.= u by A10, A77, A79, FUNCT_1:34 ;
then A80: te in u by A63, A77, A79, WAYBEL_5:9;
u in the carrier of (InclPoset (Filt (BoolePoset X))) by A10, A77, A79;
then consider FF being Filter of (BoolePoset X) such that
A81: u = FF by A1;
thus t in X by A4, A78, A80, A81; :: thesis: verum
end;
then reconsider Y = union (rng s) as Subset of X ;
set Ys = { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
;
now
let Z be set ; :: thesis: ( Z in Fs' implies Y in Z )
assume A82: Z in Fs' ; :: thesis: Y in Z
then Z in the carrier of (InclPoset (Filt (BoolePoset X))) ;
then consider FF being Filter of (BoolePoset X) such that
A83: Z = FF by A1;
s . Z in rng s by A10, A77, A82, FUNCT_1:def 5;
then A84: s . Z c= Y by ZFMISC_1:92;
A85: s . Z in dom (FD . Z) by A10, A63, A82, WAYBEL_5:9;
FD . Z is Function of (K . Z),the carrier of L by A82, WAYBEL_5:6;
then A86: dom (FD . Z) = K . Z by FUNCT_2:def 1
.= Z by A82, FUNCT_1:34 ;
reconsider sZ = s . Z as Element of (BoolePoset X) by A2, A3, A84, XBOOLE_1:1;
reconsider Y' = Y as Element of (BoolePoset X) by A3, YELLOW_1:4;
sZ <= Y' by A84, YELLOW_1:2;
hence Y in Z by A83, A85, A86, WAYBEL_0:def 20; :: thesis: verum
end;
then Y in mFs by SETFAM_1:def 1;
then A87: "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L 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 mFs
}
;
set idFFDs = { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
;
A88: { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u ) } where u is Element of Fs' : u in dom (FFD . s) } c= bool the carrier of L
proof
let t be set ; :: according to TARSKI:def 3 :: thesis: ( not t in { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
or t in bool the carrier of L )

assume t in { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
; :: thesis: t in bool the carrier of L
then consider u being Element of Fs' such that
A89: t = { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
and
u in dom (FFD . s) ;
t c= the carrier of L
proof
let v be set ; :: according to TARSKI:def 3 :: thesis: ( not v in t or v in the carrier of L )
assume v in t ; :: thesis: v in the carrier of L
then consider x being Element of (BoolePoset X) such that
A90: v = f . (uparrow x) and
A91: ex z being Element of X st
( x = {z} & z in s . u ) by A89;
consider z being Element of X such that
A92: x = {z} and
z in s . u by A91;
uparrow x in FixedUltraFilters X by A92;
hence v in the carrier of L by A90, FUNCT_2:7; :: thesis: verum
end;
hence t in bool the carrier of L ; :: thesis: verum
end;
now
let t be set ; :: thesis: ( ( t in H2(s) implies t in { (inf YY) where YY is Subset of L : YY in { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
}
) & ( t in { (inf YY) where YY is Subset of L : YY in { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
}
implies t in H2(s) ) )

hereby :: thesis: ( t in { (inf YY) where YY is Subset of L : YY in { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
}
implies t in H2(s) )
assume t in H2(s) ; :: thesis: t in { (inf YY) where YY is Subset of L : YY in { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
}

then consider u being Element of Fs' such that
A93: t = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
,L and
A94: u in dom (FFD . s) ;
{ (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u ) } c= the carrier of L
proof
let v be set ; :: according to TARSKI:def 3 :: thesis: ( not v in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
or v in the carrier of L )

assume v in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
; :: thesis: v in the carrier of L
then consider x being Element of (BoolePoset X) such that
A95: v = f . (uparrow x) and
A96: ex z being Element of X st
( x = {z} & z in s . u ) ;
consider z being Element of X such that
A97: x = {z} and
z in s . u by A96;
uparrow x in FixedUltraFilters X by A97;
hence v in the carrier of L by A95, FUNCT_2:7; :: thesis: verum
end;
then reconsider Y1 = { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
as Subset of L ;
Y1 in { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
by A94;
hence t in { (inf YY) where YY is Subset of L : YY in { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
}
by A93; :: thesis: verum
end;
assume t in { (inf YY) where YY is Subset of L : YY in { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
}
; :: thesis: t in H2(s)
then consider YY being Subset of L such that
A98: t = inf YY and
A99: YY in { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
;
consider u1 being Element of Fs' such that
A100: YY = { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u1 )
}
and
A101: u1 in dom (FFD . s) by A99;
thus t in H2(s) by A98, A100, A101; :: thesis: verum
end;
then A102: H2(s) = { (inf YY) where YY is Subset of L : YY in { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
}
by TARSKI:2;
A103: "/\" (rng (FFD . s)),L = "/\" H2(s),L by A64
.= "/\" (union { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
)
,L by A88, A102, Lm1 ;
now
let t be set ; :: thesis: ( ( t in union { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
implies t in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
) & ( t in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
implies t in union { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
) )

hereby :: thesis: ( t in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
implies t in union { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
)
assume t in union { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
; :: thesis: t 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 te being set such that
A104: t in te and
A105: te in { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
by TARSKI:def 4;
consider u being Element of Fs' such that
A106: te = { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
and
A107: u in dom (FFD . s) by A105;
consider x being Element of (BoolePoset X) such that
A108: t = f . (uparrow x) and
A109: ex z being Element of X st
( x = {z} & z in s . u ) by A104, A106;
consider z being Element of X such that
A110: ( x = {z} & z in s . u ) by A109;
s . u in rng s by A76, A77, A107, FUNCT_1:def 5;
then z in Y by A110, TARSKI:def 4;
hence t in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
by A108, A110; :: thesis: verum
end;
assume t in { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
; :: thesis: t in union { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}

then consider x being Element of (BoolePoset X) such that
A111: t = f . (uparrow x) and
A112: ex z being Element of X st
( x = {z} & z in Y ) ;
consider z being Element of X such that
A113: ( x = {z} & z in Y ) by A112;
consider ze being set such that
A114: ( z in ze & ze in rng s ) by A113, TARSKI:def 4;
consider u being set such that
A115: ( u in dom s & ze = s . u ) by A114, FUNCT_1:def 5;
reconsider u = u as Element of Fs' by A77, A115, PARTFUN1:def 4;
A116: t in { (f . (uparrow x1)) where x1 is Element of (BoolePoset X) : ex z being Element of X st
( x1 = {z} & z in s . u )
}
by A111, A113, A114, A115;
{ (f . (uparrow x1)) where x1 is Element of (BoolePoset X) : ex z being Element of X st
( x1 = {z} & z in s . u ) } in { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
by A76, A77, A115;
hence t in union { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
by A116, TARSKI:def 4; :: thesis: verum
end;
then union { { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
where u is Element of Fs' : u in dom (FFD . s)
}
= { (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 r 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 mFs
}
by A75, A87, A103, YELLOW_2:def 6; :: thesis: verum
end;
assume r 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 mFs
}
; :: thesis: r in rng (Infs )
then consider Y being Subset of X such that
A117: r = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in Y )
}
,L and
A118: Y in mFs ;
set s = Fs' --> Y;
set s' = Fs' --> Y;
A119: dom (doms FD) = dom FD by FUNCT_6:89
.= dom (Fs' --> Y) by A10, FUNCOP_1:19 ;
now
let w be set ; :: thesis: ( w in dom (doms FD) implies (Fs' --> Y) . w in (doms FD) . w )
assume w in dom (doms FD) ; :: thesis: (Fs' --> Y) . w in (doms FD) . w
then A120: w in Fs' by A119;
then A121: (doms FD) . w = dom (FD . w) by A10, FUNCT_6:31;
A122: FD . w is Function of (K . w),((Fs' --> the carrier of L) . w) by A120, PBOOLE:def 18;
(Fs' --> the carrier of L) . w = the carrier of L by A120, FUNCOP_1:13;
then A123: dom (FD . w) = K . w by A122, FUNCT_2:def 1
.= w by A120, FUNCT_1:35 ;
(Fs' --> Y) . w = Y by A120, FUNCOP_1:13;
hence (Fs' --> Y) . w in (doms FD) . w by A118, A120, A121, A123, SETFAM_1:def 1; :: thesis: verum
end;
then reconsider s = Fs' --> Y as Element of pdFD by A119, CARD_3:18;
A124: Inf = "/\" (rng (FFD . s)),L by YELLOW_2:def 6;
A125: rng (FFD . s) = H2(s) by A64;
now
let t be set ; :: thesis: ( ( t in H2(s) implies t in {r} ) & ( t in {r} implies t in H2(s) ) )
hereby :: thesis: ( t in {r} implies t in H2(s) )
assume t in H2(s) ; :: thesis: t in {r}
then consider u being Element of Fs' such that
A126: t = "/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
,L and
u in dom (FFD . s) ;
s . u = Y by FUNCOP_1:13;
hence t in {r} by A117, A126, TARSKI:def 1; :: thesis: verum
end;
assume t in {r} ; :: thesis: t in H2(s)
then A127: t = r by TARSKI:def 1;
consider u being Element of Fs';
A128: dom FD = dom (FFD . s) by A63, WAYBEL_5:8;
A129: dom s = dom FD by A63, WAYBEL_5:8;
A130: ( Fs' --> Y = s & dom (Fs' --> Y) = Fs' ) by FUNCOP_1:19;
s . u = Y by FUNCOP_1:13;
hence t in H2(s) by A117, A127, A128, A129, A130; :: thesis: verum
end;
then A131: { ("/\" { (f . (uparrow x)) where x is Element of (BoolePoset X) : ex z being Element of X st
( x = {z} & z in s . u )
}
,L) where u is Element of Fs' : u in dom (FFD . s) } = {r} by TARSKI:2;
"/\" {r},L = r by A117, YELLOW_0:39;
hence r in rng (Infs ) by A124, A125, A131, WAYBEL_5:14; :: thesis: verum
end;
hence "/\" ((f -extension_to_hom ) .: Fs),L = (f -extension_to_hom ) . ("/\" Fs,(InclPoset (Filt (BoolePoset X)))) by A32, A60, A61, A62, TARSKI:2; :: thesis: verum
end;
end;