 reserve n for Nat;

theorem ThConv7bis:
  for a,b,c being Point of TarskiEuclid2Space st
    between a,b,c holds between c,b,a
  proof
    let a,b,c be Point of TarskiEuclid2Space;
    assume between a,b,c;
    then Tn2TR b in LSeg(Tn2TR a,Tn2TR c) by ThConv6;
    hence thesis by ThConv6;
  end;
