¹ For numerous examples and case studies, see the volumes by Shelton, D. (ed.), Commitment and Compliance: The Role of Non-Binding Norms in the International Legal System (2000)Google Scholar; J. J. Kirton and M. J. Trebilcock, Hard Choices, Soft Law (2004); G. C. Shaffer and Pollack, M. A., ‘Hard vs. Soft Law: Alternatives, Complements and Antagonists in International Governance’, (2010) 94 Minnesota Law Review 706Google Scholar; Bogdandy, A. v. et al. (eds.), The Exercise of Public Authority by International Institutions: Advancing International Institutional Law (2010)CrossRefGoogle Scholar.

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³ OECD, ‘Arrangement on Officially Supported Export Credits’, January 2010 Revision, Doc. No. TAD/PG(2010)2.

⁴ C. Amerasinghe, Principles of the Institutional Law of International Organizations, 2nd edn (2005), 175.

⁵ The term ‘soft law’ was created in order to distinguish certain agreements from treaty law. The latter concept dates back to the last third of the nineteenth century; see M. Vec, Recht und Normierung in der Industriellen Revolution (2006), 112. Among the earliest examples of soft law thus understood are the ‘voeux’ contained in the Final Acts of the 1899 and 1907 Hague Peace Conferences; see Conférence Internationale de la Paix, La Haye, 18 Mai–29 Juillet 1899, Annexes, at 5; 2ème Conférence Internationale de la Paix, La Haye, 15 Juin–18 Octobre 1907, Actes et documents, Vol. I, at 700.

⁶ On the normative implications of choosing one's concept of law, see L. Murphy, ‘Better to See Law This Way’, (2008) 83 New York University Law Review 1088, at 1099–102.

⁷ Bogdandy, A. v. and Goldmann, M., ‘Taming and Framing Indicators: A Legal Reconstruction of the OECD's Programme for International Student Assessment (PISA)’, in Davis, K. E. et al. (eds.), Indicators as a Technique of Global Governance (2011)Google Scholar.

⁸ J. Habermas, Faktizität und Geltung (1992), 349; N. Luhmann, Das Recht der Gesellschaft (1993), 92, 131, especially at 134.

⁹ Cf. sections 2.3 and 3.1, infra.

¹⁰ For the Kantian tradition, see Habermas, supra note 8, at 47–9. For the opposite view, see H. L. A. Hart, The Concept of Law (1994), 202; J. Austin, The Province of Jurisprudence Determined (1832, 2001 reprint), 5.

¹¹ Raz, J., ‘Authority, Law, and Morality’, in Raz, J. (ed.), Ethics in the Public Domain (2001), 210Google Scholar, especially at 215–20.

¹² Dyzenhaus, D., ‘Hobbes and the Legitimacy of Law’, (2001) 20 Law and Philosophy 461Google Scholar.

¹³ Weiler, J. H. H., ‘The Geology of International Law: Governance, Democracy and Legitimacy’, (2004) 64 ZaöRV 547Google Scholar.

¹⁴ Cf. Koskenniemi, M., ‘Global Governance and Public International Law’, (2004) 37 Kritische Justiz 241CrossRefGoogle Scholar.

¹⁵ Foucault, M., ‘La “gouvernementalité”’, in Defert, D. and Ewald, F. (eds.), M. Foucault: Dits et Ecrits, Vol. 2 (2002), 635Google Scholar.

¹⁶ See Hart, supra note 10, at 55.

¹⁷ Cf. section 1, supra. The distinction between legal positivism and sociological positivisms does not correspond with the distinction between positivist and non-positivist approaches. The latter distinction concerns validity requirements, while the former concerns the question of whether validity matters at all.

¹⁸ U. Fastenrath, Lücken im Völkerrecht (1991), 52, calls this strand ‘psychological legal positivism’.

¹⁹ M. Koskenniemi, The Gentle Civilizer of Nations (2002), 179, especially at 181, 194.

²⁰ G. F. W. Hegel, Grundlinien der Philosophie des Rechts (1821), para. 257.

²¹ Ibid., para. 330. Hobbes took the same view on more power-oriented, rationalist grounds; cf. T. Hobbes, Leviathan (1651), Chapter XIII.

²² Koskenniemi, supra note 19, at 189.

²³ Ibid., at 191.

²⁴ H. Triepel, Völkerrecht und Landesrecht (1899), 31, 70, 82.

²⁵ G. Jellinek, Allgemeine Staatslehre (1922), 376; Bernstorff, J. v., ‘Georg Jellinek: Völkerrecht als modernes öffentliches Recht im fin de siècle?’, in Paulson, S. L. and Schulte, M. (eds.), Georg Jellinek: Beiträge zu Leben und Werk (2000), 183, at 189Google Scholar.

²⁶ On Bergbohm, see Koskenniemi, supra note 19, at 186.

²⁷ Permanent Court of International Justice, SS Lotus Case (France v. Turkey), Judgment, PCIJ Rep., (7 September 1927) Series A No. 10, at 19.

²⁸ This line of reasoning underlies the judgment of the German Federal Constitutional Court on the constitutionality of the Treaty of Lisbon, 30 June 2009, 2 BvE 2/08, BVerfGE 123, 267, at 380 (marginal note 296).

²⁹ Klabbers, J., ‘The Undesirability of Soft Law’, (1998) 67 NJIL 381Google Scholar, at 387.

³⁰ Explicitly, Weil, P., ‘Towards Relative Normativity in International Law?’, (1983) 77 AJIL 413CrossRefGoogle Scholar, at 441.

³¹ J. Klabbers, The Concept of Treaty in International Law (1996), 143.

³² W. Heusel, ‘Weiches’ Völkerrecht: Eine vergleichende Untersuchung typischer Erscheinungsformen (1991), 47, 275; similarly, Aust, A., ‘The Theory and Practice of Informal International Instruments’, (1986) 35 ICLQ 787CrossRefGoogle Scholar.

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³⁴ See Klabbers, supra note 31, at 158; he later added a positive argument (see note 29, supra).

³⁵ In the context of domestic law (‘civil law’), see Hobbes, supra note 21, Part 2, Chapter XXVI, para. 2[6], at 174.

³⁶ Habermas, supra note 8, at 118.

³⁷ A. v. Bogdandy, Gubernative Rechtsetzung (2000), 156.

³⁸ Luhmann, supra note 8, at 523–4; T. Vesting, Rechtstheorie (2007), margin note 146.

³⁹ Groundbreaking: A. Ross, Theorie der Rechtsquellen: Ein Beitrag zur Theorie des positiven Rechts auf Grundlage dogmenhistorischer Untersuchungen (1929), 34 on Montesquieu, 90 on Austin; on popular sovereignty, see C. de Montesquieu, De l'esprit des loix (1758), Book II, Chapter II.

⁴⁰ Weil, supra note 30, at 441.

⁴¹ Ibid.; Székely, A., ‘Non-Binding Commitments: A Commentary on the Softening of International Law Evidenced in the Environmental Field’, in United Nations (ed.), International Law on the Eve of the Twenty-First Century (1997), 173Google Scholar; Klabbers, supra note 29.

⁴² Klabbers, supra note 31, at 70.

⁴³ Cf. the attempt of Hobbes, supra note 21, Part 2, Chapter XXVI, para. 5[9], to interpret customary law as a command of the sovereign.

⁴⁴ A. Verdross, Die Verfassung der Völkerrechtsgemeinschaft (1926), 21; his criticism of Jellinek seems unjustified. Jellinek does not base the validity of international law solely on state consent, but rather on the objective purposes that each state pursues with the treaty and that he believes to bind the state; see M. Koskenniemi, From Apology to Utopia: The Structure of International Legal Argument (2005), 129, footnote 251.

⁴⁵ A. v. Bogdandy and S. Dellavalle, ‘Universalism and Particularism as Paradigms of International Law’, International Law and Justice Working Paper (2008), 37.

⁴⁶ H. Grotius, The Rights of War and Peace, Book 1 (1625, reprinted 1738), Preliminary Discourse, xv.

⁴⁷ Tomuschat, C., ‘Obligations Arising for States without or against Their Will’, (1994) 241 Recueil des cours 199, at 237Google Scholar.

⁴⁸ I. Kant, Die Metaphysik der Sitten (1797, reprinted 1968), para. 61 (A 227/B 257).

⁴⁹ Verdross, supra note 44, at 32.

⁵⁰ E.g., M. Knauff, Der Regelungsverbund: Recht und Soft Law im Mehrebenensystem (2010), 45 ff.

⁵¹ See, e.g., H. Lauterpacht, The Function of Law in the International Community (1933), 51; on this, Koskenniemi, supra note 19, at 361.

⁵² M. Virally, ‘La distinction entre textes internationaux ayant une portée juridique dans les relations mutuelles entre leurs auteurs et textes qui en sont dépourvus: Rapport définitif’, (1983) 60-I AIDI 328, at 341.

⁵³ M. Virally, ‘La distinction entre textes internationaux de portée juridique et textes internationaux dépourvus de portée juridique: Rapport provisoire’, (1983) 60-I AIDI 116, at 245. This is not a feature common to all international treaties; see Klabbers, supra note 31, at 89.

⁵⁴ Schachter, O., ‘The Twilight Existence of Nonbinding International Agreements’, (1977) 71 AJIL 296CrossRefGoogle Scholar, at 300; Bothe, M., ‘Legal and Non-Legal Norms: A Meaningful Distinction in International Relations?’, (1980) 11 NYIL 65CrossRefGoogle Scholar, at 95; Gruchalla-Wesierski, T., ‘A Framework for Understanding “Soft Law”’, (1984) 30 McGill Law Review 37Google Scholar; Virally, supra note 53, at 186–8; Knauff, supra note 50, at 228, seems to assume that soft law gives rise to an obligation sui generis, since he rejects both a political and a moral understanding of obligations resulting from soft law.

⁵⁵ Bothe, supra note 54, at 95.

⁵⁶ See, however, Virally, supra note 53, at 242.

⁵⁷ Heusel, supra note 32, at 275, believes that the non-legal nature of soft law is a ‘trivial’ fact. Such a conclusion is only possible if one ignores the external point of view entirely. His conclusion is not trivial, but circular.

⁵⁸ Blutman, L., ‘In the Trap of a Legal Metaphor: International Soft Law’, (2010) 59 ICLQ 605CrossRefGoogle Scholar, at 615.

⁵⁹ Ibid., at 617.

⁶⁰ Cf. Virally, supra note 53, at 246; see, further, Fastenrath, U., ‘Relative Normativity in International Law’, (1993) 4 EJIL 305CrossRefGoogle Scholar, at 308.

⁶¹ C. Schmitt, Politische Theologie (1922, reprinted 1993).

⁶² Cf. the dispute between Athens and Mytilene in Thucydides, The Peloponnesian War (translated by D. Grene) (1959).

⁶³ Hobbes, supra note 21, Chapter XIII.

⁶⁴ Groundbreaking: H. J. Morgenthau, Politics among Nations: The Struggle for Power and Peace (1949); K. N. Waltz, Theory of International Politics (1979), especially 102.

⁶⁵ G. J. H. van Hoof, Rethinking the Sources of International Law (1983), 187, therefore calls this the ‘soft law approach’.

⁶⁶ Fastenrath, supra note 18, at 84.

⁶⁷ This presupposes that a distinction between sources of law and subsidiary means for their determination is theoretically possible, as Art. 38, para. 1(d) of the ICJ Statute suggests. Even those who disagree that such a distinction is possible might agree that sources and subsidiary means can be distinguished by the different roles they play in legal discourse.

⁶⁸ See, inter alia, I. Detter, Law Making by International Organizations (1965), 207; Bothe, supra note 54; Seidl-Hohenveldern, I., ‘International Economic Soft Law’, (1979 (1980)) 163 Recueil des cours 165Google Scholar; Thürer, D., ‘Soft Law’, in Bernhardt, R. (ed.), Encyclopedia of Public International Law, 4th edn (2000), 452Google Scholar; on UN Declarations, see O. Y. Asamoah, The Legal Significance of the Declarations of the General Assembly of the United Nations (1966), 19, at 227; Virally, supra notes 52 and 53; Klabbers, supra note 31, at 188.

⁶⁹ Such instruments are now widely recognized as proper sources of law; see J. D. Aston, Sekundärgesetzgebung internationaler Organisationen zwischen mitgliedstaatlicher Souveränität und Gemeinschaftsdisziplin (2005); Benzing, M., ‘International Organizations or Institutions, Secondary Law’, in Wolfrum, R. (ed.), Max Planck Encyclopedia of Public International Law (2007)Google Scholar.

⁷⁰ Van Hoof, supra note 65, at 184. One cannot solve this problem by limiting the concept of soft law to those instruments that interact with binding law (see, however, Meyer, T., ‘Soft Law as Delegation’, (2009) 32 Fordham ILJ 888Google Scholar). It is also hard to imagine a non-binding (political) instrument that does not interact with binding international or domestic law.

⁷¹ Heusel, supra note 32, at 279.

⁷² Frowein, J. A., ‘The Internal and External Effects of Resolutions by International Organizations’, (1989) 49 ZaöRV 778Google Scholar, at 779–81.

⁷³ Cf. Heusel, supra note 32, at 275; similarly, J. E. Alvarez, International Organizations as Law-Makers (2005), 61.

⁷⁴ Eisemann, P. M., ‘Le gentlemen's agreement comme source du droit international’, (1979) 106 Journal du droit international 326Google Scholar, at 344.

⁷⁵ Falk, R. A., ‘On the Quasi-Legislative Competence of the General Assembly’, (1966) 60 AJIL 781CrossRefGoogle Scholar, at 785; Van Hoof, supra note 65, at 66; Asamoah, supra note 68.

⁷⁶ With an emphasis on jus cogens: Tasioulas, J., ‘In Defence of Relative Normativity: Communitarian Values and the Nicaragua Case’, (1996) 16 Oxford Journal of Legal Studies 85CrossRefGoogle Scholar.

⁷⁷ I. Kant, Die Metaphysik der Sitten (1797, reprinted 1968), para. 62; Kant, I., ‘Perpetual Peace: A Philosophical Sketch’ (1796), in Reiss, H. (ed.), Kant's Political Writings (1991), 93, at 105Google Scholar (third definitive article of a perpetual peace).

⁷⁸ Wengler, W., ‘Nichtrechtliche Verträge zwischen Staaten’, (1984) 22 AVR 306Google Scholar, at 307.

⁷⁹ UN Doc. A/RES/55/2, 18 September 2000.

⁸⁰ Asamoah, supra note 68, at 66.

⁸¹ Abi-Saab, G., ‘Les sources du droit international: Essai de déconstruction’, in Rama-Montaldo, M. (ed.), International Law in an Evolving World: Festschrift für E. Jiménez de Aréchaga, Vol. 1 (1994), 29, at 32, 38Google Scholar.

⁸² Van Hoof, supra note 65; in the same vein, Bos, M., ‘The Recognized Manifestations of International Law: A New Theory of “Sources”’, (1977) 20 GYIL 9Google Scholar.

⁸³ Van Hoof, supra note 65, at 53; Fastenrath, supra note 18, at 54, footnote 174, argues that Van Hoof follows a voluntaristic approach. However, Van Hoof does not see state consent as the ultimate reason for international law's validity, but the actual recognition of a secondary rule that stipulates state consent as the decisive criterion.

⁸⁴ These new manifestations complement the established sources of international law and might modify them over time; see Van Hoof, supra note 65, at 208.

⁸⁵ Van Hoof, supra note 65, at 215–79.

⁸⁶ Abi-Saab, supra note 81, at 36; see also Fastenrath, supra note 60, at 322. According to Fastenrath, supra note 18, at 88, Art. 38 of the ICJ Statute was originally intended to be enumerative.

⁸⁷ Nuclear Tests Case (Australia v. France), Judgment of 20 December 1974, [1974] ICJ Rep. 253, para. 46.

⁸⁸ Van Hoof, supra note 65, at 187.

⁸⁹ OECD Arrangement on Export Credits, TAD/PG(2011)4, 3 March 2011, para. 2.

⁹⁰ Wengler, supra note 78, at 316; with respect to the Helsinki Final Accord, J. Marquier, Soft Law: Das Beispiel des OSZE-Prozesses (2004), 193.

⁹¹ At first sight, this position resembles the view that soft law is binding by virtue of the principle of good faith (e.g., Eisemann, supra note 74, at 345; Elias, T. O., ‘Modern Sources of International Law’, in Friedmann, W. G. et al. (eds.), Transnational Law in a Changing Society (Festschrift P. C. Jessup) (1972), 34, at 51)Google Scholar. However, the latter view is based in modern legal positivism.

⁹² Dupuy, R. J., ‘Declaratory Law and Programmatory Law: From Revolutionary Custom to “Soft Law”’, in Akkerman, R. J. et al. (eds.), Declarations on Principles (1977), 247, at 255–6Google Scholar.

⁹³ Hillgenberg, H., ‘A Fresh Look at Soft Law’, (1999) 10 EJIL 499CrossRefGoogle Scholar.

⁹⁴ On the distinction between the concept of sources and specific sources, see Van Hoof, supra note 65, at 59.

⁹⁵ Hillgenberg, supra note 93, at 504, 515.

⁹⁶ E. Durkheim, Les règles de la méthode sociologique (1919), 5.

⁹⁷ B. Leiter, ‘American Legal Realism’, Public Law Research Paper (2002).

⁹⁸ On functionalism, see Alvarez, supra note 73, at 17.

⁹⁹ D. Kennedy, ‘The Move to Institutions’, (1987) 8 Cardozo Law Review 841, at 843.

¹⁰⁰ From the rich literature on this issue, see only Lipson, C., ‘Why Are Some International Agreements Informal?’, (1991) 45 IO 495Google Scholar; Brummer, C., ‘Why Soft Law Dominates International Finance – and Not Trade’, (2010) 13 Journal of International Economic Law 623CrossRefGoogle Scholar.

¹⁰¹ E.g., Chayes, A. and Chayes, A. Handler, ‘On Compliance’, (1993) 47 IO 175Google Scholar; Jacobson, H. K. and Weiss, E. Brown, ‘Strengthening Compliance with International Environmental Accords: Preliminary Observations from a Collaborative Project’, (1995) 1 Global Governance 119Google Scholar; Shelton, supra note 1.

¹⁰² On this concept, see, e.g., Klabbers, J., ‘Two Concepts of International Organizations’, (2005) 2 International Organizations Law Review 277CrossRefGoogle Scholar, at 280.

¹⁰³ E.g., Chinkin, C. M., ‘Normative Development in the International Legal System’, in Shelton, D. (ed.), Commitment and Compliance (2000), 21Google Scholar; Dupuy, P.-M., ‘Soft Law and the International Law of the Environment’, (1990–91) 12 Mich. JIL 420Google Scholar, at 431; Kirton, J. J. and Trebilcock, M. J., ‘Introduction: Hard Choices and Soft Law in Sustainable Global Governance’, in Kirton, J. J. and Trebilcock, M. J. (eds.), Hard Choices, Soft Law (2004), 3Google Scholar; Alvarez, supra note 73, at 258, emphasizing the need for a new theory of sources.

¹⁰⁴ See section 3.2, infra.

¹⁰⁵ Koh, H. H., ‘Transnational Legal Process’, (1996) 75 Nebraska Law Review 181Google Scholar, at 184.

¹⁰⁶ E.g., Falk, supra note 75, at 786; Shelton, supra note 1; Toope, S., ‘Formality and Informality’, in Bodansky, D. et al. (eds.), International Environmental Law (2007), 107, at 108Google Scholar.

¹⁰⁷ Abbott, K. W. et al. ., ‘The Concept of Legalization’, (2000) 54 IO 401Google Scholar; Abbott, K. W. and Snidal, D., ‘Hard and Soft Law in International Governance’, (2000) 54 IO 421Google Scholar.

¹⁰⁸ Abott et al. supra note 107, at 402.

¹⁰⁹ Cf. A. T. Guzman, How International Law Works: A Rational Choice Theory (2008), 71; Guzman, A. T., ‘A Compliance-Based Theory of International Law’, (2002) 90 California Law Review 1823CrossRefGoogle Scholar, at 1878; Chinkin, C., ‘A Hard Look at Soft Law’, (1988) 82 Annual Proceedings of the American Society of International Law 371Google Scholar, at 393.

¹¹⁰ Howse, R. and Teitel, R., ‘Beyond Compliance: Rethinking Why International Law Really Matters’, (2010) 1 Global Policy 127CrossRefGoogle Scholar.

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¹¹² Falk, supra note 75, at 783.

¹¹³ Onuf, N., ‘Do Rules Say What They Do? From Ordinary Language to International Law’, (1985) 26 Harv. ILJ 385Google Scholar, at 390; on transnational legal process, see Hanschmann, F., ‘Theorie transnationaler Rechtsprozesse’, in Buckel, S. et al. (eds.), Neue Theorien des Rechts (2006), 347Google Scholar.

¹¹⁴ McDougal, M. S., ‘International Law, Power and Policy: A Contemporary Conception’, (1953) 82 Recueil des cours 137Google Scholar, at 165.

¹¹⁵ Reisman, M. W., ‘The Concept and Function of Soft Law in International Politics’, in Bello, E. and Ajibola, P. B. (eds.), Essays in Honour of Judge Taslim Olawale Elias, Vol. 1 (1992), 435Google Scholar; Reisman, M. W., ‘A Hard Look at Soft Law’, (1988) 82 Annual Proceedings of the American Society of International Law 371Google Scholar, at 375.

¹¹⁶ J. L. Goldsmith and E. A. Posner, The Limits of International Law (2005).

¹¹⁷ Hobbes, supra note 21, Chapter XIII; Hegel, supra note 20, para. 330.

¹¹⁸ Goldsmith and Posner, supra note 116, at 9.

¹¹⁹ Ibid., at 85.

¹²⁰ Ibid., at 185.

¹²¹ Ibid., at 84, 90.

¹²² Ibid., at 90.

¹²³ R. M. Unger, The Critical Legal Studies Movement (1986), 2, at 5.

¹²⁴ Ibid., at 8.

¹²⁵ Kennedy, D., ‘Theses about International Law Discourse’, (1980) 23 GYIL 353Google Scholar, at 367; Koskenniemi, supra note 44, especially at 590.

¹²⁶ Koskenniemi, supra note 14.

¹²⁷ Koskenniemi, supra note 44, at 600. He calls this the ‘weak indeterminacy thesis’.

¹²⁸ Ibid., at 606.

¹²⁹ Ibid., at 616; Koskenniemi, supra note 19, at 494, especially at 500.

¹³⁰ Koskenniemi, M., ‘Formalism, Fragmentation, Freedom: Kantian Themes in Today's International Law’, (2007) 4 No Foundations: Journal of Extreme Legal Positivism 7Google Scholar, at 11; Koskenniemi, M., ‘Global Governance and Public International Law’, (2004) 37 Kritische Justiz 241CrossRefGoogle Scholar, at 243.

¹³¹ This might be justified with respect to certain views; see Koskenniemi, supra note 19, at 479.

¹³² d'Aspremont, J., ‘Hart et le positivisme postmoderne en droit international’, (2009) 113 RGDIP 635Google Scholar, at 646.

¹³³ Kammerhofer, J. and d'Aspremont, J., ‘Mapping 21st Century International Legal Positivism’, in Kammerhofer, J. and d'Aspremont, J. (eds.), International Legal Positivism in a Postmodern World (2012), forthcoming, manuscript, 8Google Scholar.

¹³⁴ d'Aspremont, J., ‘Non-State Actors from the Perspective of Legal Positivism’, in d'Aspremont, J. (ed.), Participants in the International Legal System (2011), 23, at 24Google Scholar; J. d'Aspremont, Formalism and the Sources of International Law: A Theory of the Ascertainment of Legal Rules (2011), 195.

¹³⁵ J. d'Aspremont, ‘Non-State Actors in International Law: Oscillating between Concepts and Dynamics’, in d'Aspremont, Participants in the International Legal System, supra note 134, 1, at 6; d'Aspremont, J., ‘The Politics of Deformalization in International Law’, (2011) 3 Goettingen Journal of International Law 503, at 546Google Scholar.

¹³⁶ J. d'Aspremont, ‘Inclusive Law-Making and Law-Enforcement Processes for an Exclusive International Legal System’, in d'Aspremont, Participants in the International Legal System, supra note 134, 425, at 431; d'Aspremont, ‘Non-State Actors from the Perspective of Legal Positivism’, supra note 134, at 25.

¹³⁷ Kammerhofer and d'Aspremont, supra note 133, at 8; d'Aspremont, Formalism and the Sources of International Law, supra note 134, at 186.

¹³⁸ D'Aspremont calls this the ‘normative character’ of law; cf. Formalism, supra note 134, at 29.

¹³⁹ D'Aspremont, supra note 136, at 435.

¹⁴⁰ F. Kratochwil, Rules, Norms, and Decisions (1989); Onuf, supra note 113.

¹⁴¹ Kratochwil, supra note 140, at 205.

¹⁴² Ibid., at 200.

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¹⁴⁴ Kratochwil, supra note 140, at 212.

¹⁴⁵ Ibid., at 209.

¹⁴⁶ Onuf, supra note 113, at 394; Brunnée, J. and Toope, S., ‘International Law and Constructivism: Elements of an Interactional Theory of International Law’, (2000) 39 CJTL 19Google Scholar, at 39.

¹⁴⁷ Onuf, supra note 113, at 397.

¹⁴⁸ Ibid., at 406.

¹⁴⁹ See, already, Gottlieb, G., ‘The Nature of International Law: Toward a Second Concept of Law’, in Black, C. E. and Falk, R. A. (eds.), The Future of the International Legal Order, Vol. 4: The Structure of the International Environment (1972), 331Google Scholar.

¹⁵⁰ Onuf, supra note 113, at 399.

¹⁵¹ Habermas, supra note 8, at 45.

¹⁵² Luhmann supra note 111.

¹⁵³ Luhmann supra note 8, at 38.

¹⁵⁴ Ibid., at 98.

¹⁵⁵ Ibid., at 440.

¹⁵⁶ G. Teubner and A. Fischer-Lescano, Regime-Kollisionen (2006), 37.

¹⁵⁷ Ibid., at 25.

¹⁵⁸ Ibid., at 55 (‘autoconstitutional regimes’).

¹⁵⁹ Teubner, G., ‘“Global Bukowina”: Legal Pluralism in the World Society’, in Teubner, G. (ed.), Global Law without a State (1997) 3, at 22Google Scholar.

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¹⁶⁴ L. L. Fuller, The Morality of Law (1964), 33. Those criteria are generality, promulgation, limited retroactivity, clarity, absence of contradictions, not requiring the impossible, constancy through time, and congruence between official action and declared rule.

¹⁶⁵ Brunnée and Toope, supra note 163, at 53–4, 350–2.

¹⁶⁶ Dyzenhaus, supra note 163, at 1.

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¹⁶⁹ Ibid., at 117.

¹⁷⁰ Kingsbury, B., ‘The Concept of “Law” in Global Administrative Law’, (2009) 20 EJIL 23CrossRefGoogle Scholar.

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¹⁷² Kingsbury, supra note 170, at 30.

¹⁷³ Ibid., at 32.

¹⁷⁴ Ibid., at 41.

¹⁷⁵ Kingsbury, supra note 170, at 31.

¹⁷⁶ Kingsbury, B., ‘Omnilateralism and Partial International Communities: Contributions of the Emerging Global Administrative Law’, (2005) 104 Journal of International Law and Diplomacy 98Google Scholar, at 110; cf. H. Grotius, The Rights of War and Peace, Book 3 (1625, reprinted 1738), Chapter I.

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¹⁷⁸ Klabbers, supra note 168, at 122.

¹⁷⁹ M. Weber, Wirtschaft und Gesellschaft (1922, 1972 edn), 468, Part 2, Chapter VII, para. 5.

¹⁸⁰ Grotius, supra note 46, Book 1, Chapters I, XII.

¹⁸¹ Somek, supra note 171, at 991.

¹⁸² Kingsbury, supra note 170, passim.

¹⁸³ See also N. Krisch, Beyond Constitutionalism: The Pluralist Structure of Postnational Law (2011), Chapter 7.

¹⁸⁴ Besson, S., ‘Theorizing the Sources of International Law’, in Besson, S. and Tasioulas, J. (eds.), The Philosophy of International Law (2010), 163, at 173Google Scholar; see Besson, , ‘The Authority of International Law: Lifting the State Veil’, (2010) 31 Syd. LR 343Google Scholar, at 352.

¹⁸⁵ J. Raz, The Authority of Law (1979), 5.

¹⁸⁶ J. Raz, The Morality of Freedom (1988), 22, at 53, 69.

¹⁸⁷ Besson, S., ‘Institutionalising Global Demoi-Cracy’, in Meyer, L. H. (ed.), Legitimacy, Justice and Public International Law (2009), 58CrossRefGoogle Scholar; Besson, ‘Theorizing the Sources’, supra note 184, at 178.

¹⁸⁸ Besson does not specify why she prefers deliberative mechanisms. I think that she acknowledges that deliberative institutions and procedures are promising avenues for reaching fair decisions in pluralistic societies.

¹⁸⁹ Besson, ‘Theorizing the Sources of International Law’, supra note 184, at 171.

¹⁹⁰ Ibid., at 174.

¹⁹¹ Günther, K., ‘Legal Pluralism or Uniform Concept of Law? Globalisation as a Problem of Legal Theory’, (2008) 5 No Foundations: Journal of Extreme Legal Positivism 5, at 16Google Scholar.

¹⁹² Ibid., at 18.

¹⁹³ Ibid., at 17.

¹⁹⁴ K. E. Davis, B. Kingsbury, and S. E. Merry, ‘Indicators as a Technology of Global Governance’, Institute for International Law and Justice Working Papers (2010). On PISA, see Bogdandy and Goldmann, supra note 7.

¹⁹⁵ Cf. M. Foucault, The History of Sexuality, Vol. 1 (1998), 88.

¹⁹⁶ We outline the contours of such a concept in A. v. Bogdandy, P. Dann, and M. Goldmann, ‘Developing the Publicness of International Public Law: Towards a Legal Framework for Global Governance Activities’, (2008) 9 German Law Journal 1375.

¹⁹⁷ M. Goldmann, ‘Inside Relative Normativity: From Sources to Standard Instruments for the Exercise of International Public Authority’, (2008) 9 German Law Journal 1865.

¹⁹⁸ This qualifies what I wrote in Goldmann, supra note 197, at 1907, which has been criticized by Klabbers, supra note 168, at 102. I do not think that the distinction between binding and non-binding law is elusive as a criterion for a theoretically sound distinction between different forms of authority, alongside other criteria. But the criterion of bindingness should not be equalled with the distinction between authoritative and non-authoritative acts.