There is always a danger that the legal significance will change, and the definition will become inaccurate or misleading. As Samuel Johnson has observed, "Definitions are hazardous". The definitions really heavily upon cases and authority. A deliberate effort has been made to ensure that the definitions are accurate both from an historical perspective and in light of recent development the law. The goal or these definitions is general familiarity, no effort has been made to include all the competing definitions. The second, third, and now fourth editions have expanded the definitions and have incorporated the most current authorities.