reserve n   for Nat,
        r,s for Real,
        x,y for Element of REAL n,
        p,q for Point of TOP-REAL n,
        e   for Point of Euclid n;

theorem Th14:
  RAT 0 = {0}
  proof
    RAT 0 = {<*>RAT} by FINSEQ_2:94
         .= {{}};
    hence thesis;
  end;
