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