Positivism

Author: Başak Etkin & Alex Green


Required knowledge: Link

Public International Law/History of International Law/Founding Myths

Public International Law/History of International Law/Nineteenth Century

Public International Law/Nature and Purpose of International Law

Public International Law/Approaches

Learning objectives: Understanding analytical and normative positivism and their differences from international legal positivism, identifying the major critiques of positivism.

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A. Positivism as Method and Ideology

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Legal positivism is a theory about law determination. Law determination concerns what it means for the content of the law to be 'fixed' or 'made what it is', (e.g. the threat of use of force is unlawful because art. 2.4 of the UN Charter forbids it). Legal positivism asserts that legal facts are determined by social facts, and all law is posited/positive. In this framework, law’s existence and content are determined by the social facts alone (i.e. value-neutral descriptions of social behaviour, e.g. the fact that people take their hats off when entering a church) recognized by the officials of a legal system, independently of its moral (or other) merits (the ‘social thesis’). Legal positivism first emerged as a reaction to natural law theories in the 18th century. Its roots are in the works of Jeremy Bentham[2][3] (1748–1832), who sought to criticise and reform natural law theories. Analytical legal positivism is and has been, if not the most, one of the more influential theories on modern legal theory and on international law, though some use 'positivism' to describe with the 'mainstream' doctrinal approach to international law.[4]

I. Analytical Positivism

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As their main point of convergence, all legal positivists agree upon the separability thesis (i.e. that law and morality are not necessarily linked) as it is what defines them, despite other differences. It is thanks to the separation of law and morality imposed by positivism that criticising the content of law is a possibility. However, to what degree law and morality are separated has been a point of contention between inclusive (soft) and exclusive (hard) positivists. Inclusive positivists allow for moral elements (e.g. widespread moral beliefs in a society) to be included directly or indirectly in the rule of recognition. Exclusive legal positivists, on the other hand, reject all moral element in the rule of recognition as they defend that this would make the problem of uncertainty remain unsolved. Both sides of the argument agree that when the rule of recognition does not give a clear answer to the question ‘what is the law?’, courts create law.[5]

Analytical positivism was first popularised by John Austin[6][7] (1790-1859), who developed the command theory, the concept that law consists of ‘orders backed by threats’. Here, the ‘order’ represents the command of the sovereign; this will is habitually obeyed and disobedience is sanctioned by a ‘threat’.

H.L.A. Hart (1907-1992), an English legal philosopher, inclusive legal positivist and a prominent critic of Austin, offered a comprehensive critique of the command theory in his 1961 influential book, ‘The Concept of Law’,[8] and refined legal positivism further.[9] Hart’s rebuttal demonstrated three main issues with the command theory: that it did not include customary law,[10] that not all laws commanded or prohibited specific actions,[11] and the impossibility of identifying a sovereign with unlimited law-making powers.[12] Hart proposed an alternative framework, summarised as ‘a union of primary and secondary rules’.[13] Primary rules establish obligations and confer powers to guide human conduct (e.g. it is forbidden to cross the street when the red light is on). In some communities, described by Hart as ‘primitive’, law consists solely of these primary rules, but primary rules alone do not make a legal system, which also requires secondary rules, which serve as organisational meta-rules, or rules that govern the primary rules. According to Hart, these secondary rules address three main shortcomings: (1) the uncertainty around which rules are valid in this system, (2) the static character of the rules, and (3) the inefficiency of the rules. These problems are solved by, respectively, (1) the rule of recognition, providing the criteria of legal validity and answering the question 'what is the law?', (2) the rule of change establishing the procedures for introducing new primary rules, modifying existing ones, and abolishing old ones, answering the question 'how does the law change?', and (3) the rule of adjudication determining those with the authority to adjudicate and defining the procedure to follow, answering the question 'how to implement the law?'. All secondary rules can be classified under one of these three categories.

Hart is often presented in opposition to his continental counterpart Hans Kelsen (1881-1973), an Austrian jurist, who was more influential in civil law systems. Kelsen was closer to Austin’s look than Hart, as in his view laws were norms addressed to officials and not at subjects – i.e. norms to be applied by courts if an offence was committed.[14] Another point of divergence between Hart and Kelsen was legal validity; for Hart legal validity depended on social recognition but for Kelsen legal validity was a normative ('ought' not 'is') question. He argued that legal rules are deemed valid only when formally grounded in higher norms, following the prescribed procedural frameworks. This stepped construction (Stufenbau) culminates in the concept of the Grundnorm (basic norm), as Kelsen presented in ‘Reine Rechtslehre’.[15] The Grundnorm is the presupposed legal proposition at the foundation of any legal system, a simple fiction to uphold validity.[16]

Another prominent figure in legal positivism is the Israeli legal philosopher Joseph Raz (1939-2022). In his 1979 book ‘The Authority of Law: Essays on Law and Morality’,[17] Raz developed a more modern take on the social thesis and the sources thesis (i.e., that law is identified by reference to its sources), asserting that law’s existence and content cannot rely on moral arguments, but can only be derived from social sources. As an exclusive positivist, Raz further explored the normative aspects of legal systems in ‘Practical Reasons and Norms[18] and makes the case that legal rules offer a practical justification for carrying out an obligation while excluding other justifications.

Most recently, the American legal philosopher Scott Shapiro’s book ‘Legality’ offered a new and alternative approach to legal positivism.[19] Shapiro’s planning theory of law advances the idea that legal systems are compulsory planning organizations, and his moral aim thesis suggests that law provides content-independent normative guidance to bypass moral disagreements.

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Normative positivism, perhaps more prevalent in international law than analytical positivism, defends the idea that positivism is not only true, but also valuable. Therefore analytical positivism, which does the intellectual heavy lifting, has to be true for normative positivism to even be considered. It should not be confused with normative approaches, such as Kelsen’s, as seen above. Jeremy Waldron argues that this take is more faithful to positivism’s origins, as Bentham’s intention was not to conceptually separate law and morality but to coordinate conflict resolution between the society’s laws and personal judgments about morality.[20] Lassa Oppenheim (1858-1919) also defended this point of view, suggesting that positivism was the best suited concept to advance moral and political values, as demonstrated by his advocacy of international society.[21][22] Also adopted by Prosper Weil, this has been a particularly influential approach in international law.[23]

Some aspects of analytical positivism could seem incompatible with international law, such as Austin’s command theory that could cast a doubt on its validity of, given the lack of an almighty sovereign in the international arena.[24] Another such potential issue is around pluralism and Kelsen’s account of legal validity based on normativity that favours monism (i.e. that the different branches of international law and all domestic legal systems taken together make a unified regime).[25] International law is a highly fragmented domain with numerous regional and international regimes, and it is often difficult to establish which are the hierarchically superior norms in a given situation. However, modern legal positivism has evolved quite significantly and has developed sophisticated answers to questions that arise within international law.

International legal positivism (i.e. positivism as understood and upheld by international lawyers), much like its analytical counterpart explained above, is far from being a monolith, and in some ways it diverges from legal positivism.[26][27][28] Most notably, international legal positivism is, partially because of the weight given to state will in international law, more often confused with consensualism or voluntarism.[29] However, treaties are the only consent-based source of international law, in the strict and explicit understanding of consent. Therefore, the rule of recognition of international law (which, despite some confusion, is not Article 38 of the Statute of the International Court of Justice) does not include consent and the sources thesis applied to international law does not paint a consensualist picture.[30] While neo-voluntarists survive, many contemporary international legal positivists separate the objective international legal order and the subjective will of states.[31]

International law’s compatibility with positivism is also called into question regarding jus cogens. These peremptory norms are ‘accepted and recognized […] as a norm from which no derogation is permitted’ according to the 1969 Vienna Convention on the Law of Treaties, thus the criteria does not breach the separability thesis, but one can easily identify the moral undertone once a series of examples are given: prohibitions of genocide, torture and slavery. Some exclusive legal positivists believe that acknowledging the existence of jus cogens undermines the separability thesis, but this problem can be solved by saying that the moral belief or judgment shared by states is a social fact, and that is what makes jus cogens, not its inherent moral value.[32]

B. Critiques of Positivism

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Legal positivism, as we have seen, is the view that the content of international legal norms is made what it is (that is, determined or ‘fixed’) by social facts alone. These social facts typically relate to the 'pedigree' of those norms: their historical roots in particular social sources, such as treaty texts or expressions of opinio juris. The inverse view, held by ‘non-positivists’, is that international legal norms are necessarily determined not only by social facts but also by facts about political morality,[33] which include moral values, genuine normative principles, and practical reasons that govern how individuals should 'live together', organise themselves, and behave at the collective levels of national and international society.

Example for Non-positivist approaches: Consider a more-or-less uncontroversial legal claim such as ‘the 1969 Vienna Convention on the Law of Treaties expresses true propositions of international law’. For the legal non-positivist, this statement will only be true to the extent that the law-determining function of the Vienna Convention is morally valuable in some way. This reliance upon political morality, perhaps counter-intuitively, is also entailed by the beliefs of normative positivists, like Oppenheim or Weil, who argue that for moral reasons international legal norms must be identified with recourse to social facts alone. To continue with the same example, a normative positivist and a committed non-positivist might both accept that the Vienna Convention helps to determine norms of international law because treaties in general have a coordinating function, which is valuable vis-à-vis the stability and predictability of international relations. For both schools of thought, in other words, treaty texts help to fix the content of international legal norms because there are compelling reasons why those texts should have this effect. (See: Alex Green, ‘The Precarious Rationality of International Law: Critiquing the International Rule of Recognition’ (2022) 22(8) German Law Journal 1613, 1626.)


What, then, distinguishes non-positivists from normative positivists? Non-positivists, whilst agreeing that facts about political morality partly determine the content of the law, disagree that moral reasoning should be excluded from the identification of international legal norms at a more concrete level.[34] Normative positivists, as noted above, argue that international law should be identified with recourse to social facts alone. According to their view, excluding moral considerations from legal reasoning tends to produce international stability, insofar as it avoids the proliferation of inter-state disputes. For the non-positivist, however, the exclusion of moral considerations from legal reasoning is wrongheaded, either because they believe normative positivists to be mistaken about the allegedly destabilising effects of moral reasoning,[35] or because they believe identifying international legal norms to be impossible on the basis of social facts alone. In what follows, we examine a few reasons why one might reject legal positivism wholesale, as it were, and adopt a non-positivist approach instead.

Advanced: The concrete impacts of non-positivist approaches

Non-positivist approaches to international legal reasoning differ at the interpretive and argumentative levels from their more 'formalist' positivist equivalents. In particular, a non-positivist reasoning within any given area of law may be more willing to infer legal conclusions not directly supported by clear precedents than their positivist colleagues. As such, non-positivism is often considered to be the more 'radical' or 'progressive' of the two approaches.

For example, in his non-positivist 'reconstruction' of James Crawford's famous 'The Creation of States in International Law', Alex Green identifies three broad normative commitments that run through Crawford's work on the law that governs the creation of new states. Where Crawford himself - a self-professed positivist - is hesitant to draw direct conclusions from more abstract normative principles of this kind, Green instead contends that such commitments have concrete implications for several questions related to the existence and continuity of states. In particular, he argues that when we engage in legal reasoning based on 'cautious optimism', 'nuance', and 'humanity', we are inevitably pushed towards the conclusion that Small Island Developing States should retain their legal statehood notwithstanding any losses of inhabitable land they may suffer due to human-caused climate change. (See: Alex Green 'The Creation of States as a Cardinal Point: James Crawford’s Contribution to International Legal Scholarship' 2022 40(1) AYBIL 67.)


I. Insufficient Consensus

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As we have seen, central to the positivism of Hart, Raz, and others, is the notion that legal validity turns on the existence of one or more rules of recognition. This claim can also be put in the following terms. Within any given legal order, the norms of that order are ultimately determined exclusively in relation to the convergent behaviours and attitudes of law applying officials. The social facts that such officials treat as being sources of law become sources for that reason.[36] Within international law, the relevant legal officials include state representatives and international adjudicative bodies, to name but two examples. One possible reason for rejecting this kind of positivism at the international level is that international law lacks sufficient convergence in official attitude or behaviour, meaning that no rule of recognition can be said to exist within that legal order.[37] So, for instance, although it might be true that the text of a particular bilateral investment treaty is binding on its State Parties because of their consent to be bound by that text, it nonetheless remains the case that the binding force of pacta sunt servanda requires explaining and there is little to no consensus at the international level as to the precise status of that principle (for example, whether it is a general principle of law or custom).

Example for the lack of official consensus on the sources of international law: In his paper 'The Precarious Rationality of International Law: Critiquing the International Rule of Recognition', Alex Green provides the following argument ((2022) 22(8) GLJ 1613: 1630, citations omitted): "...assume that we can discover at least some international law by identifying “international custom, as evidence of a general practice, accepted as law.” Furthermore, assume that this requires at least two things: (i) Public statements or other indications on the part of state representatives that a particular law exists; and (ii) behavior in general conformity with that proposed law on the part of such representatives. Many questions persist. Is an individual state’s consent necessary for such laws to become binding upon it? Should custom-constituting practice be drawn exclusively from state representatives? What is the relevance of UN General Assembly resolutions, or the judgments of international courts and tribunals? Can regional practice give rise to obligations limited by geographical area? Disagreement on such issues suggests that it would be overly optimistic to speak of an extensive consensus on the concrete criteria of validity for norms of customary international law, even if nominal consensus exists at higher levels of abstraction.


This view about the absence of a rule of recognition, interestingly enough, is close to the view that Hart himself professed about international law,[38] even if it has become unpopular amongst positivist international lawyers.[39] Recent scholarship has renewed attacks against positivism within international law along these lines.[40] Importantly, such criticisms raise issues not just for analytical positivism but also for normative varieties. This is so because if international law possesses no rules of recognition (or some set of norms fulfilling the same function and determined both ultimately and exclusively by social facts) then legal reasoning in a fully positivist mode is impossible, no matter how advantageous it might be in principle.

II. ‘Rational’ Determination and Social Facts

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Another doubt one may have about rules of recognition concerns the mechanics, as it were, of how such rules supposedly 'fix' the content of international law. Even if sufficiently the attitudes and behaviours of international legal officials are sufficiently convergent for one or more rules of recognition to exist, it is unclear why these attitudes and behaviours alone should be treated as determining the content of international law.[41] Why, in other words, should rules of recognition function in the way that positivists claim that they do? According to a broadly Hartian view of legal validity, the cumulative attitudes and behaviours of legal officials fix to the content of international law by definition. However, given what many non-positivists consider to be the plausible assumption that there must be a rational explanation for why legal norms exist in the way and with the content that they do, it is not obvious why official attitudes and behaviour should be treated this way.[42] For example, if we are asked to explain why pacta sunt servanda holds within international relations, it seems highly unsatisfactory to answer, 'because the relevant people believe that it does'. Positivism, understood in this way, fails to provide a sufficiently rational explanation for the existence of international law. This concern arises because the attitudes and practices of legal officials are social facts, with no necessary normative implications, and therefore cannot provide reasons why international law should be viewed one way, rather than another.[43] Importantly, this critique is inapplicable to normative positivism, which holds that facts about political morality can explain why ultimate and exclusive recourse to a particular set of social facts should be observed.[44] Nonetheless, concerns about the ‘rationality’ of positivism remain applicable to its purely analytical variants, notwithstanding this fact.

Example for 'Rational' Determination and Social Facts - An Imaginary Tribunal: Imagine that an international tribunal (‘the Tribunal’) were to deliver judgment in an ongoing case according to an absurd method: they flip a coin. When doing so, imagine the Tribunal holds that immediately prior to their decision to proceed in this manner, all the usual rules of law determination – the application of treaty texts, customary practices, and so on – were undoubtedly relevant. But all that changed, the Tribunal says, the second before their decision to resort to coin flipping was made. Clearly, the Tribunal is wrong, but why?

The state that lost the coin toss might object that the Tribunal wrongly ignored the relevant social facts. No prior item of state practice or expression of opinio juris, nor any academic or judicial commentary, mentioned that coin flipping would suddenly become the way to resolve complex legal disputes. The Tribunal, this losing state might say, is just ignoring international law. But the Tribunal could respond that this objection is mistaken because, at the moment when coin flipping became the correct way to resolve disputes, every legal rule that was previously applicable, including the ‘old’ rules for identifying international law, became irrelevant. They might also say that any current and continuing legal trends that suggest otherwise are simply mistakes: all legal orders, after all, contain at least some mistaken decisions. How can the losing state answer them?

‘Analytical’ legal positivists have no real answer to this question because everything our absurd imaginary tribunal says is logically consistent with the fact that international disputes ‘used to’ be resolved in the ‘normal way’. This holds because established legal trends, including the established attitudes and behaviour of legal officials, are social facts with no intrinsic normative implications of their own. By themselves such facts leave open the question of which standards they support and which standards they do not.

Once again, the point is not that such arguments are plausible: obviously they are ridiculous. The question is what makes them ridiculous. Non-positivists and normative positivists both have clear answers as to why: the Tribunal in this case is acting illegitimately and exceeding its authority by adopting a standard for the resolution of disputes that undermines the international rule of law. But that answer includes a value judgement – that the international rule of law is something worth promoting and defending – so it is unavailable to anyone who believes that legal argument is a matter of social facts alone.


III. The ‘Positive’ Non-Positivist Case

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Finally, one might wish to appeal directly to political morality within legal reasoning for more positive reasons. In the first place, on the assumption that either of the first two critiques presented above are true, then reliance upon more than just social facts alone is inevitable when identifying international law. This being so, there is no point, or so the argument might go, in pretending otherwise. It is preferable to be transparent about one’s reliance upon political morality, instead of obscuring it behind a positivist veneer. Alternatively, one might believe that direct recourse to moral considerations within legal reasoning would be conducive to the promotion of global justice, if for no other reason than it focuses attention on the most morally salient aspects of a given international dispute.[45] Considerations of this sort have motivated a range of contemporary non-positivist scholarship, both in relation to international law in general,[46] and as regards more discrete regimes, such as the law of statehood,[47] international trade law,[48] or the law of human rights.[49]

Further Readings

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  • Etkin, Başak (2022). "Legal Positivism". Elgar Encyclopedia of Human Rights. Edward Elgar Publishing: 412–417.
  • Hart, HLA (1994). The Concept of Law (2nd ed.). OUP.
  • Kelsen, Hans (1945). General Theory of Law and State. Translated by Wedberg, A. Harvard University Press.
  • Kelsen, Hans (1967). Pure Theory of Law. Translated by Knight, M (2nd ed.). University of California Press.
  • Raz, Joseph (2009). The Authority of Law: Essays on Law and Morality (2nd ed.). OUP.
  • d’Aspremont, Jean (2017). "International Legal Positivism". Encyclopedia of the Philosophy of Law and Social Philosophy.
  • Kammerhofer, Jörg (2016). Orford, Anne; Hoffmann, Florian (eds.). "International Legal Positivism". The Oxford Handbook of the Theory of International Law. OUP: 407–426.
  • Dire Tladi (ed), Peremptory Norms of General International Law (Jus Cogens) Disquisitions and Disputations (Brill Nijhoff 2021)
  • Nahuel Maisley (2021) Better to see international law this other way: the case against international normative positivism, Jurisprudence, 12:2, 151-174.
  • Dworkin, Ronald (1986). Law’s Empire. Hart.
  • Greenberg, Mark (2004). How Facts Make Law, 10 Legal Theory 157.

Further Resources

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Conclusion

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  • Legal positivism is a theory about law determination, asserting that legal facts are determined by social facts, and all law is posited/positive. Law’s existence and content are determined by the social facts alone recognized by the officials of a legal system, independently of its moral (or other) merits (the ‘social thesis’). As their main point of convergence, all analytical legal positivists agree upon the separability thesis (i.e. that law and morality are not necessarily linked), and that law is identified by reference to its sources (the 'sources thesis').
  • Normative positivism defends the idea that positivism is not only true but also valuable. This has been a particularly influential approach in positivism as understood and upheld by international lawyers, international legal positivism. Some aspects of analytical positivism could seem incompatible with international law, but these issues no longer arise in modern legal positivism or are due to a confusion between positivism and other concepts (such as consensualism).
  • The inverse view, held by ‘non-positivists’, is that international legal norms are necessarily determined not only by social facts but also by facts about political morality, which include moral values, genuine normative principles, and practical reasons that govern how individuals should 'live together', organise themselves, and behave at the collective levels of national and international society. Non-positivists, whilst agreeing with normative positivists that facts about political morality partly determine the content of the law, disagree that moral reasoning should be excluded from the identification of international legal norms at a more concrete level.
  • Three issues illustrate non-positivism in international law. (1) There is insufficient consensus about a or the rule of recognition in international law. (2) Even if it existed, it is unclear how such rules supposedly 'fix' the content of international law, since many non-positivists consider to be the plausible assumption that there must be a rational explanation for why legal norms exist in the way and with the content that they do. (3) It is preferable to be transparent about one’s reliance upon political morality, instead of obscuring it behind a positivist veneeer, and one might believe that direct recourse to moral considerations within legal reasoning would be conducive to the promotion of global justice.

Table of Contents

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Part I - History, Theory, and Methods

Part II - General International Law

Part III - Specialized Fields

Footnotes

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  1. The first footnote. Please adhere to OSCOLA when formating citations. Whenever possible, provide a link with the citation, ideally to an open-access source.
  2. Bentham, Jeremy (1970). Of Laws in General (unpublished manuscript, eds HLA Hart). Athlone Press.
  3. Bentham, Jeremy (1996). An Introduction to the Principles of Morals and Legislation (first published 1789, Burns JH and Hart HLA eds). OUP.
  4. Bianchi, Andrea (2016). International Law Theories: An Inquiry into Different Ways of Thinking. New York: Oxford University Press. pp. 22–43.
  5. Especially when facing extra-legal notions such as ’proportional’ or ‘reasonable’.
  6. Austin, John (1995). The Province of Jurisprudence Determined (first published 1832). CUP.
  7. Austin, John (2002). Campbell, R (ed.). Lectures on Jurisprudence, or the Philosophy of Positive Law (first published 1879) (4th ed.). Thoemmes Press.
  8. Hart, HLA (1994). The Concept of Law (2nd ed.). OUP.
  9. Hart, HLA. "Positivism and the Separation of Law and Morals". Harvard Law Review. 71: 593.
  10. Id. 44-49.
  11. Id. 27-44.
  12. Id. 66-71.
  13. Id. 79-99.
  14. Kelsen, Hans (1945). General Theory of Law and State. Translated by Wedberg, A. Harvard University Press. pp. 58–64.
  15. Kelsen, Hans (1967). Pure Theory of Law. Translated by Knight, M (2nd ed.). University of California Press.
  16. Id. 193-221.
  17. Raz, Joseph (2009). The Authority of Law: Essays on Law and Morality (2nd ed.). OUP.
  18. Raz, Joseph (1999). Practical Reasons and Norms (2nd ed.). OUP.
  19. Shapiro, Scott (2011). Legality. Belknap Press.
  20. Waldron, Jeremy (2001). "Normative (or Ethical) Positivism". In Coleman, J (ed.). Hart’s Postscript: Essays on the Postscript to ‘The Concept of Law’. OUP.
  21. Oppenheim, Lassa (April 1908). "The Science of International Law: Its Task and Method". American Journal of International Law. 2 (2): 313–356.
  22. Kingsbury, Benedict (April 2002). "Legal Positivism as Normative Politics: International Society, Balance of Power and Lassa Oppenheim's Positive International Law". European Journal of International Law. 13 (2): 401–437.
  23. Weil, Prosper (July 1983). "Towards Relative Normativity in International Law?". American Journal of International Law. 77 (3): 413–442.
  24. On Enforcement, see Quiroga-Villamarín, § 2.3, in this textbook.
  25. For more: on Interaction within International Law, see Rachovitsa, § 5.1, in this textbook; on International Law and Domestic Law, see Kunz, § 5.2, in this textbook.
  26. Etkin, Başak (2022). "Legal Positivism". Elgar Encyclopedia of Human Rights. Edward Elgar Publishing: 412–417.
  27. d’Aspremont, Jean (2017). "International Legal Positivism". Encyclopedia of the Philosophy of Law and Social Philosophy.
  28. Kammerhofer, Jörg (2016). Orford, Anne; Hoffmann, Florian (eds.). "International Legal Positivism". The Oxford Handbook of the Theory of International Law. OUP: 407–426.
  29. On Consent, see González Hauck, § 2.2, in this textbook.
  30. On Sources, see Eggett, § 6, in this textbook.
  31. Kammerhofer, Jörg; d’Aspremont, Jean, eds. (2014). International Legal Positivism in a Post-Modern World. CUP.
  32. Hameed, Asif (2014). "Unravelling the Mystery of Jus Cogens in International Law". British Yearbook of International Law (84): 52.
  33. Hasan Dindjer, ‘The New Legal Anti-Positivism’ (2020) 26(3) Legal Theory 181.
  34. Ronald Dworkin, Law’s Empire (Hart 1986) 114-130, 238-258. The distinction as presented here may elide non-positivism and ‘soft’ positivism, which accepts that moral reasoning can indeed form part of legal reasoning but only to the extent that moral norms are ‘incorporated’ within the law by norms that are themselves determined ultimately and exclusively by social facts. For more on soft positivism, see: Eleni Mitrophanous, ‘Soft Positivism’ (1997) 17(4) Oxford Journal of Legal Studies 621.
  35. Nahuel Maisley, ‘Better to See International Law this Other Way: The Case Against International Normative Positivism’ (2021) 12(2) Jurisprudence 151.
  36. Green (n XXX) 1619-1620.
  37. Ibid 1627-1633.
  38. H.L.A. Hart, The Concept of Law (OUP 1994) 236.
  39. Jeremy Waldron, ‘International Law: “A Relatively Small and Unimportant” Part of Jurisprudence?’ in Luís Duarte d’Almeida, James Edwards, and Andrea Dolcetti (eds.), Reading H.L.A. Hart’S ‘The Concept of Law’ 209, 219–22 (Bloomsbury 2013); Mehrdad Payandeh, ‘The Concept of International Law in the Jurisprudence of H.L.A. Hart’ (2010) 21 European Journal of International Law 967, 989–93.
  40. Green (n XXX); David Lefkowitz, ‘What Makes a Social Order Primitive? In Defense of Hart’s Take on International Law’ (2017) 23(4) Legal Theory 258.
  41. Mark Greenberg, ‘Hartian Positivism and Normative Facts: How Facts Make Law II’ in Scott Hershovitz (ed.), Exploring Law’s Empire: The Jurisprudence of Ronald Dworkin (OUP 2006) 273.
  42. Mark Greenberg, ‘How Facts Make Law’ (2004) 10 Legal Theory 157, 164.
  43. Greenberg (n XXX).
  44. Green (n XXX) 1626-1627.
  45. John Tasioulas, ‘Customary International Law and the Quest for Global Justice’ in Amanda Perreau-Saussine and James Murphy, The Nature of Customary Law (CUP 2007) 326-329.
  46. Fernando Teson, A Philosophy of International Law (Perseus 1998); Ronald Dworkin, ‘A New Philosophy for International Law’ (2013) 41(1) Philosophy & Public Affairs 2.
  47. Alex Green, Statehood as Political Community: International Law and the Emergence of New States (forthcoming, CUP 2023).
  48. Oisin Suttle, Distributive Justice and World Trade Law: A Political Theory of International Trade Regulation (CUP 2018).
  49. George Letsas, A Theory of Interpretation of the European Convention on Human Rights (OUP 2007).