public static Proposition getRule(Stella_Object rulename) {
    { Stella_Object renamed_Object = Logic.getInstance(rulename);

      if ((renamed_Object == null) ||
          (!Stella_Object.isaP(renamed_Object, Logic.SGT_LOGIC_PROPOSITION))) {
        {
          System.out.println("Can't find a rule named `" + rulename + "'");
          System.out.println();
        }
;
        return (null);
      }
      return (((Proposition)(renamed_Object)));
    }
  }