The Concept of Law (ISBN 0-19-876122-8) is the most famous work of the legal philosopher H. L. A. Hart. Jurisprudence is the Theory and Philosophy of Law. Scholars of jurisprudence or legal philosophers hope to obtain a deeper understanding of the nature Herbert Lionel Adolphus Hart (1907-1992 was an influential English-speaking legal philosopher of the twentieth century. It was first published in 1961 and develops Hart's theory of legal positivism (the view that laws are rules made by human beings and that there is no inherent or necessary connection between law and morality) within the framework of analytic philosophy. Year 1961 ( MCMLXI) was a Common year starting on Sunday (link will display full calendar of the Gregorian calendar. Legal positivism is a school of thought in Jurisprudence and the Philosophy of law. Morality (from the Latin la moralitas "manner character proper behavior" has three principal meanings Analytic philosophy (sometimes analytical philosophy) is a generic term for a style of Philosophy that came to dominate English-speaking countries in the 20th century In this work, Hart sets out to write an essay of descriptive sociology and analytical jurisprudence. Sociology (from Latin: socius "companion" and the suffix -ology "the study of" from Greek λόγος lógos "knowledge" Analytical jurisprudence is a Legal theory that draws on the resources of modern Analytical philosophy to try to understand the nature of law The Concept of Law provides an explanation to a number of traditional jurisprudential questions such as "what is law?", "must laws be rules?", and "what is the relation between law and morality?". Hart answers these by placing law into a social context while at the same time leaving the capability for rigorous analysis of legal terms. As a result Hart's view has remained one of the most influential in jurisprudence.
The book emerged from a set of lectures that Hart began to deliver in 1952, and it is presaged by his Holmes lecture, Positivism and the Separation of Law and Morals delivered at Harvard Law School. Harvard Law School (also known as Harvard Law or HLS) is one of the professional Graduate schools of Harvard University. The Concept of Law developed a sophisticated view of legal positivism.
Among the many ideas developed in this book are:
In recent years Hart's Concept has been criticised from a number of perspectives including postmodern critique of Professor Saint Lazare 
The starting point for the discussion is Hart's dissatisfaction with John Austin's "Command Theory": a jurisprudential concept that holds that law is command backed by threat and is meant to be ubiquitous in its application. John Austin (1790 - 1859 was a noted British Jurist and published extensively concerning the philosophy of law and Jurisprudence. Hart likens Austin's theory to the role of a gunman in a bank and tries to establish the differences between the gunman's orders and those made by law. A banker or bank is a Financial institution whose primary activity is to act as a payment agent for customers and to borrow and lend money (For instance, the gunman forces us to obey but we may not feel inclined to obey him. Presumably, obedience to the law comes with a different feeling. )
Hart identifies three such important differences: content, origin, and range. In terms of content, not all laws are imperative or coercive. Coercion (co-er-shion is the practice of compelling a person or manipulating them to behave in an involuntary way (whether through action or inaction by use of threats Some are facilitative, allowing us to create contracts and other legal relations. A contract is an exchange of promises between two or more parties to do or refrain from doing an act which is enforceable in a court of law
Austin believed that every legal system had to have a sovereign who creates the law (origin) whilst remaining unaffected by it (range), such as the bank scene's gunman, who is the only source of commands and who is not subject to other's commands. Sovereignty is the exclusive Right to control a Government, a country, a people or oneself Hart argues that this is an inaccurate description of law, noting that laws may have several sources and legislators are very often subject to the laws they create.
Hart draws a distinction between a social habit (which people follow habitually but where breaking the habit does not bring about opprobrium - going to the cinema on Thursday for example) and a social rule (where breaking the rule is seen as wrong). Habits are habituated routines of behavior that are repeated regularly tend to occur Subconsciously and tend to occur without directly thinking consciously We feel in some sense bound by social rules and laws frequently appear to be types of social rule.
There are two perspectives to this: the external aspect, which is the independently observable fact that people do tend to obey the rule with regularity, and the internal aspect which is the feeling by an individual of being in some sense obligated to follow the rule, otherwise known as the critical reflective attitude. It is from this internal sense that the law acquires its normative quality. The obedience by the populace of a rule is called efficacy. No law can be said to be efficacious unless followed by the majority of the populace. Though an average citizen in a modern state with a developed legal system may feel the internal aspect and be compelled to follow the laws, it is more important for the officials of the society/peoples to have the internal aspect since it is up to them to follow the constitutional provisions which, if they wish, could ignore without accountability. Yet, the officials must use the internal aspect and accept the standards as guiding their behavior in addition to also guiding the behavior of other officials.
But laws are more than rules of conduct. Laws can be divided up into two sorts: primary rules (rules of conduct) and secondary rules (rules addressed to officials and which set out to affect the operation of primary rules). Secondary rules deal with three problems: first the problem of uncertainty about what the law is (the secondary rule for this dilemma is called the rule of recognition and states the criteria of validity of a law), second the problem of rigidity of rules (which requires rules of change allowing laws to be varied), and third the problem of how to resolve legal disputes (from which rules of adjudication arise). A legal system is "the union of primary and secondary rules. "
Lastly, Hart lets us know that laws are much broader in scope than coercive orders, contrary to the "command theory" of Austin. Frequently laws are enabling and so allow citizens to carry out authoritative acts such as the making of wills or contracts which have legal effect.