let R1, R2 be real RelStr ; ( the carrier of R1 = the carrier of R2 implies RelStr(# the carrier of R1, the InternalRel of R1 #) = RelStr(# the carrier of R2, the InternalRel of R2 #) )
assume A1:
the carrier of R1 = the carrier of R2
; RelStr(# the carrier of R1, the InternalRel of R1 #) = RelStr(# the carrier of R2, the InternalRel of R2 #)
set X = the carrier of R1;
the InternalRel of R1 = the InternalRel of R2
proof
let a,
b be
object ;
RELAT_1:def 2 ( ( not [a,b] in the InternalRel of R1 or [a,b] in the InternalRel of R2 ) & ( not [a,b] in the InternalRel of R2 or [a,b] in the InternalRel of R1 ) )
A2:
the
carrier of
R1 c= REAL
by Def1;
assume A5:
[a,b] in the
InternalRel of
R2
;
[a,b] in the InternalRel of R1
then A6:
(
a in the
carrier of
R1 &
b in the
carrier of
R1 )
by A1, ZFMISC_1:87;
then reconsider a9 =
a,
b9 =
b as
Element of
REAL by A2;
a9 <= b9
by A1, A5, A6, Def1;
hence
[a,b] in the
InternalRel of
R1
by A6, Def1;
verum
end;
hence
RelStr(# the carrier of R1, the InternalRel of R1 #) = RelStr(# the carrier of R2, the InternalRel of R2 #)
by A1; verum