You SHOULD Read This
RFC 2119 specifies the definition of several terms used throughout RFC specifications. In the specifications which utilize these terms they are always capitalized as if the document is yelling at you from its dry, technical pages. Keywords such as “MUST,” “SHALL,” and “REQUIRED” tell the reader of this document what they must, shall, and are required to do. The technical specifications which use these keywords define interfaces. These interfaces ensure that software and hardware systems are able to interact with each other; it keeps them on the same page.
Although our own lives are rarely as clean-cut as an RFC specification, they too are interspersed with moral, legal, and interpersonal cries of MUST and SHOULD. Morality, laws, and social norms create interfaces between people. They specify that one MUST NOT murder another; they specify that one SHOULD cover one’s mouth when sneezing. In many aspects of our lives, a significant portion of these guidelines are utterly unenforceable. Even areas we see constantly being enforced are far from absolutely enforced. Although there are many speeding tickets issued in the United States each year, there is far from a 100% correlation between a driver exceeding the speed limit and being issued a citation. It is simply not possible to enforce such regulations at an absolute level using current policing strategies.
Software provides better and more sophisticated mechanisms to enforce regulations. In the United Kingdom several types of vehicles including mopeds and heavy transport vehicles are legally required to be fitted with speed limiting devices. Devices of this type (and their analogs in software) can “monitor” activity with a far more effectively than any previous solutions. These devices, however, go beyond simply monitoring activity to direct enforcement. A moped MUST NOT exceed a speed of 30 miles per hour. Even more advanced mechanisms for enforcement are now up for consideration. A 2013 article outlines a proposal for GPS tracking and/or speed sign detection mechanisms to be employed to limit motorist speeds. See explanatory graphic below.
Defaults are powerful. Defaults which are in reality REQUIRED (such as vehicle speed limiters) are even more powerful. The Great Firewall of China is imperfect. It is able to be circumvented by even mildly skilled technical individuals. Even so, the default is powerful; it is effective in the general case.
From this case and others, you may see that software provides new and more effective methods of enforcing moral, legal, and social MUSTs, SHOULDs, and MAYs. It is therefore imperative that as tools for enforcing MUSTs and SHOULDs improve that the justice and righteousness of these guidelines are without question.