The philosophy of law is concerned with all aspects of theoretical reflection on laws and legal systems and therefore encompasses historical and sociological studies in addition to the philosophical questions posed by general jurisprudence (a word that usually connotes the theory or system of law, but is sometimes used synonymously with philosophy of law). The philosophical questions are largely concerned with problems internal to law, such as the nature and scope of legal rules, the individuation of different legal systems, and the sort of reasoning employed in legal decisions.
One major line of debate concerns the relationship between our legal obligations and other sources of normativity. According to natural law theorists, there is a close relationship between law and morality either because legal systems are themselves necessarily morally good or because obeying the law is always morally desirable. By contrast, legal positivists argue that the conditions for being a legal system are purely formal, such as the de facto existence of a recognized source of legal authority or a coherent set of legal obligations. The positivists therefore argue that there could be a legitimate legal system that was nevertheless morally iniquitous. Similarly, while some philosophers maintain that legal adjudication is
ultimately a formal matter of conceptual analysis (that is, applying the law as it stands), others maintain that there is an ineliminable element of interpretation and assert that legal rules are better thought of as general predictions of future court behavior. Answers to these questions, however, are not purely theoretical, and such issues often come to the fore at the highest level of legal adjudication, or in debate regarding the legitimacy of international law.
