English translation of the second edition of Reine Rechtslehre published in 1960 (a major expansion and revision of the book of the same name from 1934). With Hart 1997 one of the most important statements of legal positivism in the 20th century. Kelsen`s positivism, however, was somewhat less influential among English-speaking legal philosophers. Kelsen is difficult, but it is essential reading for graduate students and scientists. These three theses establish links between law and morality that are both necessary and of great importance. Each of them is consistent with the positivist thesis that the existence and content of the law depend on social facts and not on the merits of the law. Each of them contributes to the understanding of the nature of the law. The once popular notion that legal positivism insists on the separability of law and morality is therefore grossly false. However, it may seem that legal positivism requires at least an attitude towards the so-called « factual value » problem.
There is no doubt that some positivists, especially Kelsen, believe so. In reality, positivism here can coexist with a number of views – statements of value can be provoked by statements of fact; Values can overlay facts; Values can be facts. Legal positivism only demands that something be law because of its factuality and not because of its authority of merit, and that we can describe that factuality without judging its merits. If the legal arguments are primarily, or even partially, about [the characteristics that make a proposition valid], then not all lawyers can use the same factual criteria to decide when legal propositions are true and false. Their arguments would revolve mainly or partly around the criteria they should use. The project of semantic theories, the project of unearthing common rules from a careful study of what jurists say and do, would thus be doomed to failure (Dworkin 1986, p. 43). According to Hart, it would be an exaggeration to ask the majority of the population to accept the rule of recognition as the ultimate criterion for legal validity: « The reality of the situation is that a large proportion of ordinary citizens – perhaps a majority – have no general idea of the legal structure or its criteria for validity » (Hart 1994, p. 111).
Instead, Hart argues that for a legal system to exist, it is necessary for the majority of officials to adopt the internal position on the recognition rule and its criteria for validity. Citizens are simply required to generally abide by the primary rules that are legally valid under the recognition rule. Hart, for his part, acknowledges that the powers of judicial legislation are limited in two respects: « Not only are the powers of the judge subject to many constraints which limit his choice, of which a legislature may be completely free, but since the powers of the judge are exercised only to deal with certain cases, he cannot use them to introduce large-scale reforms or new codes » (Hart, 1994, p. 273). What explains the judge`s discretion to enact a new law in a particular case, according to Hart, is not the absence of legal norms limiting his decision; Rather, it is the absence of legal norms that prescribes a clearly correct answer to the case. The judge cannot decide such a case solely by applying the existing law, since there is more than one result that is consistent with the applicable law. In such cases, it is impossible to make a substantive decision (as opposed to a simple reference to Parliament) without creating a new law. These rights have not been granted by any government – they are intrinsically our demands, and no government that denies them is just. The legal positivist might argue that we only have such rights if they are recognized and granted by the government. Logical positivists such as Rudolf Carnap and A. J. Ayer proposed another important principle of legal positivism: namely, that sentences and the use of words must be studied in order to understand reality.
 A sentence has a literal meaning only if it expresses something that is tautologous or empirically verifiable.  Despite its similarity to this earlier critique, Dworkin`s semantic argument serves a deeper purpose. The semantic spur refers to all so-called semantic legal theories, which define the concept of law in the sense of « common rules ». established the criteria that give meaning to the word » (Dworkin 1986, p. 31). Thus, while the preceding critique is directed against Hart`s alien presentation of social rules, the semantic spur is directed against what Dworkin sees as the core of the theoretical core of positivism, namely the assertion that there are common criteria that exhaust the conditions for the correct application of the concept of law. Although Hart introduced the rule of recognition by speculative anthropology, as it might arise in response to flaws in a common social order, he was not attached to the idea that law was a cultural achievement. On the contrary, the idea that the rule of law is always a good thing and that societies are imperfect without it is a familiar element of many antipositivist views, beginning with Henry Maine`s critique of Austin on the grounds that his theory would not apply to certain Native American villages. The objection includes the error he wants to avoid.
It imperialistically assumes that it is always a bad thing not to have a law, and then draws a blinding conclusion from the should: if it is good to have a law, then every society must have it, and the concept of law must be adapted to show that it does. If one thinks that the law is a complex issue, one will be tempted by a very broad understanding of the law, because it would be inappropriate to accuse others of failing.