let x, y, z be Element of (FinSups f); YELLOW_0:def 2 ( not x <= y or not y <= z or x <= z )
assume that
A1:
x <= y
and
A2:
y <= z
; x <= z
A3:
( ex g being Function of (Fin J), the carrier of L st
for x being Element of Fin J holds
( g . x = sup (f .: x) & FinSups f = NetStr(# (Fin J),(RelIncl (Fin J)),g #) ) & InclPoset (Fin J) = RelStr(# (Fin J),(RelIncl (Fin J)) #) )
by WAYBEL_2:def 2, YELLOW_1:def 1;
then reconsider x1 = x, y1 = y, z1 = z as Element of (InclPoset (Fin J)) ;
y1 <= z1
by A2, A3;
then A4:
y1 c= z1
by YELLOW_1:3;
x1 <= y1
by A1, A3;
then
x1 c= y1
by YELLOW_1:3;
then
x1 c= z1
by A4;
then
x1 <= z1
by YELLOW_1:3;
hence
x <= z
by A3; verum