let i, j be Element of NAT ; for C being compact non horizontal non vertical Subset of (TOP-REAL 2) st C is connected & i <= j holds
RightComp (Cage (C,j)) c= RightComp (Cage (C,i))
let C be compact non horizontal non vertical Subset of (TOP-REAL 2); ( C is connected & i <= j implies RightComp (Cage (C,j)) c= RightComp (Cage (C,i)) )
assume
( C is connected & i <= j )
; RightComp (Cage (C,j)) c= RightComp (Cage (C,i))
then A1:
Cl (LeftComp (Cage (C,i))) c= Cl (LeftComp (Cage (C,j)))
by Th55, PRE_TOPC:49;
( (Cl (LeftComp (Cage (C,i)))) ` = RightComp (Cage (C,i)) & (Cl (LeftComp (Cage (C,j)))) ` = RightComp (Cage (C,j)) )
by Th50;
hence
RightComp (Cage (C,j)) c= RightComp (Cage (C,i))
by A1, SUBSET_1:31; verum