theorem Satz6p24:
  for S being satisfying_A8 TarskiGeometryStruct
  ex a,b,c being POINT of S st not Collinear a,b,c
  proof
    let S be satisfying_A8 TarskiGeometryStruct;
    consider a,b,c being POINT of S such that
A1: not between a,b,c and
A2: not between b,c,a and
A3: not between c,a,b by GTARSKI2:def 7;
    not Collinear a,b,c by A1,A2,A3;
    hence thesis;
  end;
