Law is a set of rules that govern the behavior of people in a community and are enforced by a controlling authority through penalties. It is a field of study that covers many different aspects of society, such as criminal, civil, property, administrative, and international law. The most common purpose of a legal system is to establish standards, maintain order, resolve disputes, and protect liberties and rights. Some systems of law serve these purposes better than others. For example, a nation with an authoritarian government may keep the peace and maintain social stability, but it can also oppress minorities and restrict dissenting views. Alternatively, an intergovernmental organization might create law in a way that promotes social justice and allows for a peaceful and orderly transition to a new social order.

The precise definition of law is a subject of ongoing debate. Law is a social construct that can be defined as a system of rules that are created and enforced by governmental or other social institutions to regulate behaviour and which, as a whole, constitutes the Rule of Law. The concept of law reflects the ambivalence of human beings about the nature and role of power in the social world. The concept of law is therefore a central topic in philosophy, political science, history, and economic analysis.

Various scholarly approaches to law exist, but the most prominent ones share certain basic features. The first is an emphasis on rationality in decision making. This is based on the notion that decisions should be made based on an individual’s predictions about how a particular action will intersect with an external reality shaped by other people’s narratives. The second feature is the importance of legitimacy. This is the idea that people are willing to accept a regime of laws only if it is transparent and accountable. James Madison emphasized this point in the Federalist Papers when he wrote that no one person should be able to exercise total power over the lives of the people.

The emergence of a coherent body of law requires considerable human effort and cooperation. Most of the detailed rules that make up law are not written down but rather ad hoc, with each institution developing its own rules. This is a major part of the reason why legal systems are so diverse. Some systems, such as Roman law, are well-documented and remain intact today, but other countries have a much more fragmentary legal heritage. For example, modern legislation often consists only of a frame-working statute that authorizes agencies to develop much more elaborate rules that must be conveyed in modes that are congenial to legalistic concerns about clarity and predictability. Fuller 1964 formulated principles of what he called the “inner morality of law” that seem to be indispensable to law-making. Yet these are largely abstract, theoretical concepts that cannot be verified empirically.