ConRelat P,Q is_transitive_in field (ConRelat P,Q)
proof
set X =
field (ConRelat P,Q);
set R =
ConRelat P,
Q;
for
x,
y,
z being
set st
x in field (ConRelat P,Q) &
y in field (ConRelat P,Q) &
z in field (ConRelat P,Q) &
[x,y] in ConRelat P,
Q &
[y,z] in ConRelat P,
Q holds
[x,z] in ConRelat P,
Q
proof
let x,
y,
z be
set ;
( x in field (ConRelat P,Q) & y in field (ConRelat P,Q) & z in field (ConRelat P,Q) & [x,y] in ConRelat P,Q & [y,z] in ConRelat P,Q implies [x,z] in ConRelat P,Q )
assume B0:
(
x in field (ConRelat P,Q) &
y in field (ConRelat P,Q) &
z in field (ConRelat P,Q) &
[x,y] in ConRelat P,
Q &
[y,z] in ConRelat P,
Q )
;
[x,z] in ConRelat P,Q
set X1 =
ConFuncs P,
Q;
B1:
field (ConRelat P,Q) c= ConFuncs P,
Q
by LemConRelat01;
ConRelat P,
Q is_transitive_in ConFuncs P,
Q
by LemConRelat03;
hence
[x,z] in ConRelat P,
Q
by B0, B1, RELAT_2:def 8;
verum
end;
hence
ConRelat P,
Q is_transitive_in field (ConRelat P,Q)
by RELAT_2:def 8;
verum
end;
hence
ConRelat P,Q is transitive
by RELAT_2:def 16; verum