let S be non empty non void ManySortedSign ; for A being non-empty MSAlgebra of S
for C1, C2 being MSCongruence of A
for G being ManySortedFunction of (QuotMSAlg A,C1),(QuotMSAlg A,C2) st ( for i being Element of S
for x being Element of the Sorts of (QuotMSAlg A,C1) . i
for xx being Element of the Sorts of A . i st x = Class C1,xx holds
(G . i) . x = Class C2,xx ) holds
G ** (MSNat_Hom A,C1) = MSNat_Hom A,C2
let A be non-empty MSAlgebra of S; for C1, C2 being MSCongruence of A
for G being ManySortedFunction of (QuotMSAlg A,C1),(QuotMSAlg A,C2) st ( for i being Element of S
for x being Element of the Sorts of (QuotMSAlg A,C1) . i
for xx being Element of the Sorts of A . i st x = Class C1,xx holds
(G . i) . x = Class C2,xx ) holds
G ** (MSNat_Hom A,C1) = MSNat_Hom A,C2
let C1, C2 be MSCongruence of A; for G being ManySortedFunction of (QuotMSAlg A,C1),(QuotMSAlg A,C2) st ( for i being Element of S
for x being Element of the Sorts of (QuotMSAlg A,C1) . i
for xx being Element of the Sorts of A . i st x = Class C1,xx holds
(G . i) . x = Class C2,xx ) holds
G ** (MSNat_Hom A,C1) = MSNat_Hom A,C2
set sL = the Sorts of (QuotMSAlg A,C1);
let G be ManySortedFunction of (QuotMSAlg A,C1),(QuotMSAlg A,C2); ( ( for i being Element of S
for x being Element of the Sorts of (QuotMSAlg A,C1) . i
for xx being Element of the Sorts of A . i st x = Class C1,xx holds
(G . i) . x = Class C2,xx ) implies G ** (MSNat_Hom A,C1) = MSNat_Hom A,C2 )
assume A1:
for i being Element of S
for x being Element of the Sorts of (QuotMSAlg A,C1) . i
for xx being Element of the Sorts of A . i st x = Class C1,xx holds
(G . i) . x = Class C2,xx
; G ** (MSNat_Hom A,C1) = MSNat_Hom A,C2
now let i be
set ;
( i in the carrier of S implies (G ** (MSNat_Hom A,C1)) . i = (MSNat_Hom A,C2) . i )assume
i in the
carrier of
S
;
(G ** (MSNat_Hom A,C1)) . i = (MSNat_Hom A,C2) . ithen reconsider s =
i as
SortSymbol of
S ;
A2:
for
c being
Element of the
Sorts of
A . s holds
((G . s) * ((MSNat_Hom A,C1) . s)) . c = ((MSNat_Hom A,C2) . s) . c
proof
let c be
Element of the
Sorts of
A . s;
((G . s) * ((MSNat_Hom A,C1) . s)) . c = ((MSNat_Hom A,C2) . s) . c
Class (C1 . s),
c in Class (C1 . s)
by EQREL_1:def 5;
then A3:
Class C1,
c is
Element of the
Sorts of
(QuotMSAlg A,C1) . s
by MSUALG_4:def 8;
thus ((G . s) * ((MSNat_Hom A,C1) . s)) . c =
(G . s) . (((MSNat_Hom A,C1) . s) . c)
by FUNCT_2:21
.=
(G . s) . ((MSNat_Hom A,C1,s) . c)
by MSUALG_4:def 18
.=
(G . s) . (Class C1,c)
by MSUALG_4:def 17
.=
Class C2,
c
by A1, A3
.=
(MSNat_Hom A,C2,s) . c
by MSUALG_4:def 17
.=
((MSNat_Hom A,C2) . s) . c
by MSUALG_4:def 18
;
verum
end; thus (G ** (MSNat_Hom A,C1)) . i =
(G . s) * ((MSNat_Hom A,C1) . s)
by MSUALG_3:2
.=
(MSNat_Hom A,C2) . i
by A2, FUNCT_2:113
;
verum end;
hence
G ** (MSNat_Hom A,C1) = MSNat_Hom A,C2
by PBOOLE:3; verum