Before exploring some positivist answers, it bears emphasizing that these are not the only questions worth asking.
It can be seen throughout social theory, particularly in the works of Marx, Weber, and Durkheim, and also (though here unwittingly) among many lawyers, including the American “legal realists” and most contemporary feminist scholars.
Although they disagree on many other points, these writers all acknowledge that law is essentially a matter of social fact.
Legal positivism has a long history and a broad influence.
It has antecedents in ancient political philosophy and is discussed, and the term itself introduced, in mediaeval legal and political thought (see Finnis 1996).
Legal positivism is the thesis that the existence and content of law depends on social facts and not on its merits.
The English jurist John Austin (1790-1859) formulated it thus: “The existence of law is one thing; its merit and demerit another.Its emphasis on legislative institutions was replaced by a focus on law-applying institutions such as courts, and its insistence of the role of coercive force gave way to theories emphasizing the systematic and normative character of law. Hart (1907-92) and Joseph Raz among whom there are clear lines of influence, but also important contrasts.The most important architects of this revised positivism are the Austrian jurist Hans Kelsen (1881-1973) and the two dominating figures in the analytic philosophy of law, H. Legal positivism's importance, however, is not confined to the philosophy of law.For much of the next century an amalgam of their views, according to which law is the command of a sovereign backed by force, dominated legal positivism and English philosophical reflection about law.By the mid-twentieth century, however, this account had lost its influence among working legal philosophers.Whether it be or be not is one enquiry; whether it be or be not conformable to an assumed standard, is a different enquiry.” (1832, p.157) The positivist thesis does not say that law's merits are unintelligible, unimportant, or peripheral to the philosophy of law.The modern doctrine, however, owes little to these forbears.Its most important roots lie in the conventionalist political philosophies of Hobbes and Hume, and its first full elaboration is due to Jeremy Bentham (1748-1832) whose account Austin adopted, modified, and popularized.Some of them are, it is true, uncomfortable with the label “legal positivism” and therefore hope to escape it.Their discomfort is sometimes the product of confusion.