theorem ThMak6:
  for S being (RE') (TE) (IE) (SC) non empty TarskiGeometryStruct holds
    S is (RE)
  proof
    let S be (RE') (TE) (IE) (SC) non empty TarskiGeometryStruct;
    let a,b be POINT of S;
    per cases;
    suppose a = b;
      hence thesis by Satz2p8;
    end;
    suppose
A1:   a <> b;
      between b,a,a & S is (RE') by Satz3p1;
      hence thesis by A1,Satz2p2bis;
    end;
  end;
