let P, Q be non empty strict chain-complete Poset; ConRelat (P,Q) is_antisymmetric_in ConFuncs (P,Q)
set X = ConFuncs (P,Q);
reconsider R = ConRelat (P,Q) as Relation of (ConFuncs (P,Q)) ;
for x, y being set st x in ConFuncs (P,Q) & y in ConFuncs (P,Q) & [x,y] in R & [y,x] in R holds
x = y
proof
let x,
y be
set ;
( x in ConFuncs (P,Q) & y in ConFuncs (P,Q) & [x,y] in R & [y,x] in R implies x = y )
assume B1:
(
x in ConFuncs (
P,
Q) &
y in ConFuncs (
P,
Q) &
[x,y] in R &
[y,x] in R )
;
x = y
then consider f,
g being
Function of
P,
Q such that B2:
(
x = f &
y = g &
f <= g )
by DefConRelat;
consider g1,
f1 being
Function of
P,
Q such that B3:
(
y = g1 &
x = f1 &
g1 <= f1 )
by B1, DefConRelat;
thus
x = y
by B2, B3, Lemlessthan03;
verum
end;
hence
ConRelat (P,Q) is_antisymmetric_in ConFuncs (P,Q)
by RELAT_2:def 4; verum