The law is the set of rules that a community develops and enforces to ensure that people live together peacefully. These laws can cover any aspect of human society, from a simple traffic rule to the complex systems that govern land ownership and the rights of businesses. Laws can be formal or informal, but they must be clear and comprehensive. They must also be enforceable and capable of changing as social circumstances change.
For this reason, legal systems vary greatly among nations. The main functions of a nation-state’s law are to keep the peace, preserve property, defend minorities from majorities, promote social justice, and allow for orderly social change. Some national governments are able to accomplish these goals better than others.
Some aspects of law are regulated by treaties, but most are decided in national courts and legislatures. A country’s constitution, for example, sets out the basic principles of its legal system. Laws may also be based on religious or philosophical doctrine. Aristotle’s ancient Athens, for instance, had a well-developed legislative body and a system of trials — though its courts were quite rudimentary by modern standards.
Because laws can affect a wide variety of human activities, they often have to be very complicated. They must address many questions, including who has the right to make them, when they can be changed, and how they will be applied to different situations. They must also be enforceable, so they are effective against the kinds of behavior that might otherwise undermine their purposes and lead to disorder.
The study of the law is a complex and fascinating activity, both because of the many interesting problems it raises and because it provides insights into the nature of human society. It has a distinct character that makes it unique even against the background of empirical science (as in the law of gravity) and social sciences (such as the law of supply and demand).
It is also distinct from other forms of philosophy. While all philosophical speculation is in part a product of the time, place, and culture in which it occurs, speculation about law takes on an additional parochial quality. This is because discussions of law usually are carried out with a particular kind of legal system and culture in mind.
There are numerous specialized fields in law, covering such areas as zoning and environmental protection; family law, including divorce proceedings and the rights of children; criminal law, addressing offenses against individuals; tort law, covering cases involving injury to persons or their property; constitutional and administrative law, governing the structures of government; and tax and banking laws, dealing with regulations that affect the amounts of money that banks must hold and how taxes are collected and paid. A broad category, international law, deals with issues that cross national boundaries, such as treaties and the legal status of people in outer space. The study of these specialized fields is important for anyone interested in the workings of law as it applies to human society.