reserve o,m for set;
reserve C for Cartesian_category;
reserve a,b,c,d,e,s for Object of C;

theorem Th46:
  for f,g being Morphism of c1Cat*(o,m) holds f = g
proof
  let f,g be Morphism of c1Cat*(o,m);
  f = m by TARSKI:def 1;
  hence thesis by TARSKI:def 1;
end;
