Jurisprudence is the science , study , and theory of law . It includes principles behind law that make the law. Scholars of jurisprudence, also known as jurists or legal theorists (including legal philosophers and social theorists of law), hope to obtain a deeper understanding of the nature of law, of legal reasoning, legal systems , and of legal institutions. Modern jurisprudence began in the 18th century and was focused on the first principles of the natural law , civil law , and the law of nations . General jurisprudence can be divided into categories both by the type of question scholars seek to answer and by the theories of jurisprudence, or schools of thought, regarding how those questions are best answered. Contemporary philosophy of law, which deals with general jurisprudence, addresses problems in two rough groups:
- Problems internal to law and legal systems.
- Problems of law as a particular social institution as law relates to the larger political and social situation in which it exists.
Answers to these questions come from four primary schools of thought in general jurisprudence: 
- Natural law is the idea that there are rational objective limits to the power of legislative rulers. The foundations of law are accessible through reason and it is from these laws of nature that human-created laws gain whatever force they have.
- Legal positivism , by contrast to natural law, holds that there is no necessary connection between law and morality and that the force of law comes from some basic social facts. Legal positivists differ on what those facts are.
- Legal realism is a third theory of jurisprudence which argues that the real world practice of law is what determines what law is; the law has the force that it does because of what legislators, lawyers and judges do with it.
- Critical legal studies are a younger theory of jurisprudence that has developed since the 1970s. It is primarily a negative thesis that holds that the law is largely contradictory, and can be best analyzed as an expression of the policy goals of the dominant social group.
Also of note is the work of the contemporary philosopher of law Ronald Dworkin who has advocated a constructivist theory of jurisprudence that can be characterized as a middle path between natural law theories and positivist theories of general jurisprudence.
The English word is based on the Latin maxim jurisprudentia : juris is the genitive form of jus meaning "law", and prudentia means "prudence" (also: discretion, foresight, forethought, circumspection; refers to the exercise of good judgment, common sense, and even caution, especially in the conduct of practical matters). The word is first attested in English in 1628, at a time when the word prudence had the meaning of "knowledge of or skill in a matter". The word may have come via the French jurisprudence , which is attested earlier.
History of Jurisprudence
Ancient Indian jurisprudence is available in various Dharmaśāstra texts starting from the Dharmasutra of Bhodhayana. Jurisprudence already had this meaning in Ancient Rome even if at its origins the discipline was a ( periti ) in the jus of mos maiorum (traditional law), a body of oral laws and customs verbally transmitted "by father to son". Praetors established a workable body of laws by judging whether or not singular cases were capable of being prosecuted either by the edicta, the annual pronunciation of prosecutable offense, or in extraordinary situations, additions made to the edicta. An iudex then would judge a remedy according to the facts of the case.
Their sentences were supposed to be simple interpretations of the traditional customs, but effectively it was an activity that, apart from formally reconsidering for each case what precisely was traditionally in the legal habits, soon turned also to a more equitable interpretation, coherently adapting the law to the newer social instances. The law was then implemented with new evolutive Institutiones (legal concepts), while remaining in the traditional scheme. Praetors were replaced in the 3rd century BC by a laical body of prudentes . Admission to this body was conditional upon proof of competence or experience.
Under the Roman Empire , schools of law were created, and the activity constantly became more academic. In the age from the early Roman Empire to the 3rd century, a relevant literature was produced by some notable groups including the Proculians and Sabinians . The scientific depth of the studies was unprecedented in ancient times.
After the 3rd century, Juris prudentia became a more bureaucratic activity, with few notable authors. It was during the Eastern Roman Empire (5th century) that legal studies were once again undertaken in depth, and it is from this cultural movement that Justinian 's Corpus Juris Civilis was born.
In its general context, natural law theory may be compared to both state-of-nature law and general law understood on the basis of an analogy to the physical laws of science. Natural law is often contrasted to positive law which asserts law as the product of human activity and human volition.
Another approach to natural law jurisprudence generally asserts that human law may be supported by decisive reasons for action. In other words, there must be a compelling rationale behind following human law. There are two readings of the natural law jurisprudential stance.
- The Strong Natural Law Thesis holds that if a human law fails to be backed-up by decisive reasons, then it is not properly called a “law” at all. This is captured, imperfectly, in the famous maxim: lex iniusta non est lex' (an unjust law is no law at all).
- The Weak Natural Law Thesis holds that If a human law fails to be backed-up by decisive reasons, then it can still be called a “law”, but it must be recognised as a defective law.
Notions of an objective moral order, external to human legal systems, underlie natural law. What is right or wrong can vary according to the interests one is focused upon. Natural law is sometimes identified with the maxim that "an unjust law is no law at all", but as John Finnis , the most important of modern natural barristers have argued, this maxim is a poor guide to the classical Thomist position. Strongly related to theories of natural law are classical theories of justice , beginning in the West with Plato ’s Republic .
Aristotle is often said to be the father of natural law. Like his philosophical forefathers Socrates , Plato, and other Indian philosophers, Aristotle posited the existence of natural justice or natural right ( dikaion physikon , δικαίον φυσικόν , Latin is natural ). His association with natural law is largely due to the way in which he was interpreted by Thomas Aquinas . This was based on Aquinas' conflation of natural law and natural right, the latter of which Aristotle posits in Book V of the Nicomachean Ethics (= Book IV of the Eudemian Ethics ). Aquinas's influence was such as to affect a number of early translations of these passages, though more recent translations render them more literally.
Aristotle's theory of justice is bound up in his idea of the golden mean . Indeed his treatment of what he calls "political justice" derives from his discussion of "the just" as a moral virtue derived as the mean between opposing vices, just like every other virtue he describes. His longest discussion of his theory of justice occurs in Nicomachean Ethics and begins by asking what sort of mean a just act is. He argues that the term "justice" actually refers to two different but related ideas: general justice and particular justice. When a person's actions are completely virtuous in all matters in relation to others, Aristotle calls them "just" in the sense of "general justice;" as such this idea of justice is more or less coextensive with virtue. "Particular" or "partial justice", by contrast, is the part of "general justice" or the individual virtue that is concerned with treating others equitably. Aristotle moves from this unqualified discussion of justice to a qualified view of political justice, by which he means something close to the subject of modern jurisprudence. Of political justice, Aristotle argues that it is partly derived from nature and partly a matter of convention. This can be taken as a statement that is similar to the views of modern natural law theorists. But it must also be remembered that Aristotle is describing a view of morality, not a system of law, and therefore his remarks as to nature are about the grounding of the morality enacted as law, not the laws themselves. The passage here is silent as to that question.
The best evidence of Aristotle's having thought there was a natural law comes from the Rhetoric , where Aristotle notes that, aside from the "particular" laws that each people has set up for itself, there is a "common" law that is according to nature. The context of this remark, however, suggests only that Aristotle thought that it could be rhetorically advantageous to appeal to such a law, especially when the "particular" law of ones' own city was adverse to the case being made, not that there actually was such a law; Aristotle, moreover, considered two of the three candidates for a universally valid, natural law suggested in this passage to be wrong. Aristotle's theoretical paternity of the natural law tradition is consequently disputed.
Saint Thomas Aquinas, [Thomas of Aquin, or Aquino] (c. 1225 – 7 March 1274) was an Italian philosopher and theologian in the scholastic tradition, known as "Doctor Angelicus, Doctor Universalis". He is the foremost classical proponent of natural theology , and the father of the Thomistic school of philosophy, for a long time the primary philosophical approach of the Roman Catholic Church . The work for which he is best known is the Summa Theologica . One of the thirty-five Doctors of the Church , he is considered by many Catholics to be the Church's greatest theologian. Consequently, many institutions of learning have been named after him.
Aquinas distinguished four kinds of law: eternal, natural, human and divine:
- Eternal law refers to divine reason, known only to God. It is God's plan for the universe. Man needs this, for without it he would totally lack direction.
- Natural law is the "participation" in the eternal law by rational human creatures, and is discovered by reason.
- Divine law is revealed in the scriptures and is God's positive law for mankind.
- Human law is supported by reason and enacted for the common good.
Natural law, of course, is based on "first principles":
. . . this is the first precept of the law, that good is to be done and promoted, and evil is to be avoided. All other precepts of the natural law are based on this . . . 
The desires to live and to procreate are counted by Aquinas among those basic (natural) human values on which all other human values are based.
School of Salamanca
Francisco de Vitoria was perhaps the first to develop a theory of ius gentium (the rights of peoples), and thus is an important figure in the transition to modernity. He extrapolated his ideas of legitimate sovereign power to society at the international level, concluding that this scope as well ought to be ruled by just forms respectable of the rights of all. The common good of the world is of a category superior to the good of each state. This meant that relations between states ought to pass from being justified by force to being justified by law and justice. Some scholars have upset the standard account of the origins of International law, which emphasises the seminal text De iure belli ac pacis by Grotius, and argued for Vitoria and, later, Suárez's importance as forerunners and, potentially, founders of the field. Others, such as Koskenniemi, have argued that none of these humanist and scholastic thinkers can be understood to have founded international law in the modern sense, instead placing its origins in the post-1870 period.
Francisco Suárez , regarded as among the greatest scholastics after Aquinas, subdivided the concept of ius gentium . Working with already well-formed categories, he carefully distinguished ius inter gentes from ius intra gentes . Ius inter gentes (which corresponds to modern international law) was something common to the majority of countries, although, being positive law, not natural law, was not necessarily universal. On the other hand, ius intra gentes , or civil law, is specific to each nation.
In his treatise Leviathan, (1651) , Hobbes expresses a view of natural law as a precept , or general rule, found out by reason , by which a man is forbidden to do that which is destructive of his life, or takes away the means of preserving the same; and to omit that by which he thinks it may best be preserved. Hobbes was a social contractarian and believed that the law gained peoples' tacit consent. He believed that society was formed from a state of nature to protect people from the state of war between mankind that exists otherwise. Life is, without an ordered society, "solitary, poor, nasty, brutish and short". It is commonly commented that Hobbes' views about the core of human nature were influenced by his times. The English Civil War and the Cromwellian dictatorship had taken place, and he felt absolute authority vested in a monarch, whose subjects obeyed the law, was the basis of a civilized society.
Writing after World War II , Lon L. Fuller notably emphasised that the law must meet certain formal requirements (such as being impartial and publicly knowable). To the extent that an institutional system of social control falls short of these requirements, Fuller argues, we are less inclined to recognise it as a system of law, or to give it our respect. Thus, law has an internal morality that goes beyond the social rules by which valid laws are made.
Sophisticated positivist and natural law theories sometimes resemble each other more than the above descriptions might suggest, and they may concede certain points to the other "side". Identifying a particular theorist as a positivist or a natural law theorist sometimes involves matters of emphasis and degree, and the particular influences on the theorist's work. In particular, the older natural lawyers, such as Aquinas and John Locke made no distinction between analytic and normative jurisprudence. But modern natural lawyers, such as John Finnis claim to be positivists, while still arguing that law is a basically moral creature.
Sharia and Fiqh in Islam
Sharia ( شَرِيعَةٌ ) refers to the body of Islamic law , which is the most widely used religious law in the world. The term means "way" or "path"; it is the legal framework within which public and most private aspects of life are regulated for those living in a legal system based on Islamic principles of jurisprudence. Fiqh is the term for Islamic jurisprudence, made up of the rulings of Islamic jurists. A component of Islamic studies, Fiqh expounds the methodology by which Islamic law is derived from primary and secondary sources.
Mainstream Islam distinguishes fiqh , which means understanding the details and inferences drawn by scholars, from sharia , which refers to the principles behind the fiqh . Scholars hope that fiqh and sharia are in harmony in any given case, but this cannot be assured.
Early forms of logic in Islamic philosophy were introduced in Islamic jurisprudence from the 7th century with the process of Qiyas . During the Islamic Golden Age , there was a logical debate among Islamic philosophers and jurists over whether the term Qiyas refers to analogical reasoning , inductive reasoning or categorical syllogism . Some Islamic scholars argued that Qiyas refers to reasoning. Ibn Hazm (994-1064) disagreed with this, arguing that Qiyas refers rather to categorical syllogism in a real sense and to analogical reasoning in a metaphorical sense. On the other hand, al-Ghazali (1058–1111) argued that Qiyas refers to analogical reasoning in a real sense and categorical syllogism in a metaphorical sense. Other Islamic scholars at the time argued that the term Qiyas refers to both analogical reasoning and categorical syllogism in a real sense.
Analytic, or 'clarificatory', jurisprudence means the use of a neutral point of view and descriptive language when referring to the aspects of legal systems. This was a philosophical development that rejected natural law's fusing of what law is and what it ought to be. David Hume famously argued in A Treatise of Human Nature  that people invariably slip between describing that the world is a certain way to saying therefore we ought to conclude on a particular course of action. But as a matter of pure logic, one cannot conclude that we ought to do something merely because something is the case. So analysing and clarifying the way the world is must be treated as a strictly separate question to normative and evaluative ought questions.
The most important questions of analytic jurisprudence are: "What are laws?"; "What is the law?"; "What is the relationship between law and power/sociology?"; and "What is the relationship between law and morality?" Legal positivism is the dominant theory, although there are a growing number of critics who offer their own interpretations.
Positivism simply means that law is something that is "posited": laws are validly made in accordance with socially accepted rules. The positivist view on law can be seen to cover two broad principles: Firstly, that laws may seek to enforce justice, morality, or any other normative end, but their success or failure in doing so does not determine their validity. Provided a law is properly formed, in accordance with the rules recognized in the society concerned, it is a valid law, regardless of whether it is just by some other standard. Secondly, that law is nothing more than a set of rules to provide order and governance of society. No legal positivist, however, argues that it follows that the law is therefore to be obeyed, no matter what. This is seen as a separate question entirely.
- What the law is ( lex lata ) - is determined by historical social practice (resulting in rules)
- What the law ought to be ( lex ferenda ) - is determined by moral considerations.
Bentham and Austin
One of the earliest legal positivists was Jeremy Bentham. Bentham was an early and staunch supporter of the utilitarian concept (along with Hume), an avid prison reformer, advocate for democracy , and strongly atheist . Bentham's views about law and jurisprudence were popularized by his student, John Austin . Austin was the first chair of law at the new University of London from 1829. Austin's utilitarian answer to "what is law?" was that law is "commands, backed by threat of sanctions, from a sovereign, to whom people have a habit of obedience". Contemporary legal positivists have long abandoned this view, and have criticised its oversimplification, H. L. A. Hart particularly.
Hans Kelsen is considered one of the prominent jurists of the 20th century and has been highly influential in Europe and Latin America, although less so in common-law countries. His Pure Theory of Law aims to describe law as binding norms while at the same time refusing, itself, to evaluate those norms. That is, 'legal science' is to be separated from 'legal politics'. Central to the Pure Theory of Law is the notion of a 'basic norm ( Grundnorm )'—a hypothetical norm, presupposed by the jurist, from which in a hierarchy all 'lower' norms in a legal system , beginning with constitutional law , are understood to derive their authority or 'bindingness'. In this way, Kelsen contends, the bindingness of legal norms, their specifically 'legal' character, can be understood without tracing it ultimately to some suprahuman source such as God, personified Nature or—of great importance in his time—a personified State or Nation.
H. L. A. Hart
In th Anglophone world, the pivotal writer was H. L. A. Hart , who argued that the law should be understood as a system of social rules. Hart rejected Kelsen's views that sanctions were essential to law and that a normative social phenomenon, like law, can not be grounded in non-normative social facts. Hart revived analytical jurisprudence as an important theoretical debate in the twentieth century through his book The Concept of Law . As the professor of jurisprudence at Oxford University , Hart argued that law is a 'system of rules'.
Rules, said Hart, are divided into primary rules (rules of conduct) and secondary rules (rules addressed to officials to administer primary rules). Secondary rules are divided into rules of adjudication (to resolve legal disputes), rules of change (allowing laws to be varied) and the rule of recognition (allowing laws to be identified as valid). The "rule of recognition" is a customary practice of the officials (especially barristers and judges) that identifies certain acts and decisions as sources of law. A pivotal book on Hart was written by Neil MacCormick  in 1981 (second edition due in 2007), which further refined and offered some important criticisms that led MacCormick to develop his own theory (the best example of which is his recently published Institutions of Law , 2007). Other important critiques have included that of Ronald Dworkin, John Finnis, and Joseph Raz .
In recent years, debates about the nature of law have become increasingly fine-grained. One important debate is within legal positivism. One school is sometimes called exclusive legal positivism , and it is associated with the view that the legal validity of a norm can never depend on its moral correctness. A second school is labeled inclusive legal positivism , a major proponent of which is Wil Waluchow, and it is associated with the view that moral considerations may determine the legal validity of a norm, but that it is not necessary that this is the case.
Some philosophers used to contend that positivism was the theory that there is "no necessary connection" between law and morality; but influential contemporary positivists, including Joseph Raz, John Gardner, and Leslie Green, reject that view. As Raz points out, it is a necessary truth that there are vices that a legal system cannot possibly have (for example, it cannot commit rape or murder).
Joseph Raz defends the positivist outlook, but criticised Hart's "soft social thesis" approach in The Authority of Law . Raz argues that law is authority, identifiable purely through social sources, without reference to moral reasoning. Any categorisation of rules beyond their role as authority is better left to sociology than to jurisprudence.
In his book Law's Empire Dworkin attacked Hart and the positivists for their refusal to treat law as a moral issue. Dworkin argues that law is an 'interpretive' concept, that requires barristers to find the best-fitting and most just solution to a legal dispute, given their constitutional traditions. According to him, law is not entirely based on social facts, but includes the morally best justification for the institutional facts and practices that we intuitively regard as legal. It follows on Dworkin's view that one cannot know whether a society has a legal system in force, or what any of its laws are, until one knows some moral truths about the justifications for the practices in that society. It is consistent with Dworkin's view—in contrast with the views of legal positivists or legal realists—that no-one in a society may know what its laws are, because no-one may know the best justification for its practices.
Interpretation, according to Dworkin's law as integrity theory, has two dimensions. To count as an interpretation, the reading of a text must meet the criterion of fit . Of those interpretations that fit, however, Dworkin maintains that the correct interpretation is the one that puts the political practices of the community in their best light, or makes of them the best that they can be . But many writers have doubted whether there is a single best justification for the complex practices of any given community, and others have doubted whether, even if there are, they should be counted as part of the law of that community.
Legal realism was a view popular with some Scandinavian and American writers. Skeptical in tone, it held that the law should be understood and determined by the actual practices of courts, law offices, and police stations, rather than as the rules and doctrines set forth in statutes or learned treatises. It had some affinities with the sociology of law. The essential tenet of legal realism is that all law is made by human beings and, thus, is subject to human foibles, frailties and imperfections.
It has become quite common today to identify Justice Oliver Wendell Holmes, Jr., as the main precursor of American Legal Realism (other influences include Roscoe Pound , Karl Llewellyn and Justice Benjamin Cardozo ). Karl Llewellyn, another founder of the U.S. legal realism movement, similarly believed that the law is little more than putty in the hands of a judge who is able to shape the outcome of a case based on personal biases. The chief inspiration for Scandinavian legal realism many consider to be the works of Axel Hägerström . Despite its decline in popularity, realism continues to influence a wide spectrum of jurisprudential schools today, including critical legal studies, feminist legal theory , critical race theory , sociology of law and law and economics . 
Historical jurisprudence came to prominence during the German debate over the proposed codification of German law. In his book On the Vocation of Our Age for Legislation and Jurisprudence , Friedrich Carl von Savigny argued that Germany did not have a legal language that would support codification because the traditions, customs and beliefs of the German people did not include a belief in a code. The Historicists believe that the law originates with society.
In addition to the question, "What is law?", legal philosophy is also concerned with normative, or "evaluative" theories of law. What is the goal or purpose of law? What moral or political theories provide a foundation for the law? What is the proper function of law? What sorts of acts should be subject to punishment , and what sorts of punishment should be permitted? What is justice? What rights do we have? Is there a duty to obey the law? What value has the rule of law? Some of the different schools and leading thinkers are as follows.
Aretaic moral theories such as contemporary virtue ethics emphasize the role of character in morality. Virtue jurisprudence is the view that the laws should promote the development of virtuous characters by citizens. Historically, this approach is associated mainly with Aristotle or Thomas Aquinas later. Contemporary virtue jurisprudence is inspired by philosophical work on virtue ethics.
Deontology is "the theory of duty or moral obligation." The philosopher Immanuel Kant formulated one influential deontological theory of law. He argued that any rule we follow must be able to be universally applied, i.e. we must be willing for everyone to follow that rule. A contemporary deontological approach can be found in the work of the legal philosopher Ronald Dworkin.
Utilitarianism is the view that the laws should be crafted so as to produce the best consequences for the greatest number of people possible. Historically, utilitarian thinking about law is associated with the philosopher Jeremy Bentham. John Stuart Mill was a pupil of Bentham's and was the torch bearer for utilitarian philosophy through the late nineteenth century.  In contemporary legal theory, the utilitarian approach is frequently championed by scholars who work in the law and economics tradition. 
John Rawls was an American philosopher, a professor of political philosophy at Harvard University and author of A Theory of Justice (1971), Political Liberalism , Justice as Fairness: A Restatement , and The Law of Peoples . He is widely considered one of the most important English-language political philosophers of the 20th century. His theory of justice uses a device called the original position to ask us which principles of justice we would choose to regulate the basic institutions of our society if we were behind a 'veil of ignorance.' Imagine we do not know who we are - our race, sex, wealth status, class, or any distinguishing feature - so that we would not be biased in our own favour. Rawls argues from this 'original position' that we would choose exactly the same political liberties for everyone, like freedom of speech, the right to vote and so on. Also, we would choose a system where there is only inequality because that produces incentives enough for the economic well-being of all society, especially the poorest. This is Rawls's famous 'difference principle'. Justice is fairness, in the sense that the fairness of the original position of choice guarantees the fairness of the principles chosen in that position.
There are many other normative approaches to the philosophy of law, including critical legal studies and libertarian theories of law .
- Analytical jurisprudence
- Artificial intelligence and law
- Brocard (law)
- Cautelary jurisprudence
- Comparative law
- Constitutional law
- Constitutional economics
- Critical legal studies
- Critical race theory
- Defeasible reasoning
- Divine law
- Feminist jurisprudence
- Feminist legal theory
- International legal theory
- Judicial activism
- Law and economics
- Law and literature
- Legal formalism
- Legal history
- Legal pluralism
- Legal positivism
- Legal realism
- Libertarian theories of law
- Living Constitution
- Natural law
- New legal realism
- Political jurisprudence
- Postmodernist jurisprudence
- Publius Juventius Celsus
- Philosophy of law
- Rule of law
- Rule according to higher law
- Sociological jurisprudence
- Sociology of law
- Strict interpretation
- Virtue jurisprudence