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John Austin is widely regarded as the successor to the jurisprudential ideas of Jeremy Bentham. As an early defender of Legal positivism, Austin wrote a great deal about what he considered the incoherence of Natural law jurisprudence, which confused (deliberately or otherwise) the concepts of law 'as it presently is' with law 'as it ought to be'. According to Austin, 'The existence of law is one thing; its merit or demerit is another'.

Austin argued that law could be studied and analyzed without recourse to normative claims regarding the law 'as it should be'. As an example of this conceptual confusion, he provided a passage from Blackstone's Commentaries on the Laws of England, the gist of which is that the 'laws of God are superior to the laws of man', and that 'human laws have no validity if contrary to the laws of God'. Austin was at pains to point out that this what not necessarily a proposition with which he disagreed; however, the claim mixed notions of what law is, with what it should be, to the extent that it was in the end impossible to actually agree or disagree. Indeed, Blackstone might have meant that the formation of human law should be guided by the principles of justice. On the other hand, he might have intended that a law at odds with the dictates of justice was, in some way or other, not a 'law' at all. Austin repudiated the second notion, suggesting that what differentiates law from non-law is not whether it is just or not, but whether it can be enforced or not.

Because, in Austin's view, laws were nothing more than 'commands backed by threat of applying force in the case of noncompliance', he was very much concerned with questions of sovereignty. His conception of law necessarily included some entity in the supreme political position of 'sovereign' that served as the source, and not the subject, of the legal system's set of 'commands backed by threats'. In the case of England, Austin identified this source of supreme authority as Parliament, thus suggesting the model of Parliamentary supremacy still prevalent to this day.

More recently, writers such as H.L.A. Hart have criticised Austin's 'command theory of law' as being far too simplistic to explain the complexities of modern legal systems.