¹ Throughout this article, I will use the terms ‘duty’ and ‘obligation’ interchangeably.

² UDHR, Preamble.

³ For instance, the International Covenant on Economic, Social and Cultural Rights (ICESCR) is more specific about the human right to work, claiming that it can only be fully realized by steps that include, among other measures, ‘technical and vocational guidance and training programs’ for citizens (Article 6.2).

⁴ Consider, for instance, Article 12 (b), which claims, without adding any further detail, that state parties must take the ‘steps necessary for: the improvement of all aspects of environmental and industrial hygiene’ (my emphasis).

⁵ See Shue, Henry, ‘Thickening Convergence’, The Ethics of Assistance: Morality and the Distant Needy, ed. Chatterjee, D. K. (Cambridge, 1996), pp. 217–41, at 226–7Google Scholar; Shue, Henry, Basic Rights: Subsistence, Affluence, and U.S. Foreign Policy (Princeton, 1996), e.g. p. 157Google Scholar.

⁶ For instance, according to some, the inattention of human rights culture towards concrete matters of responsibility signals its lack of appreciation for the significance of ‘community’, the ‘social dimension’ of human life, or the interdependence of human beings (see e.g. Glendon, Mary Ann, Rights Talk: The Impoverishment of Political Discourse (New York, 1991)Google Scholar, ch. 4; Etzioni, Amitai, The Spirit of Community (New York, 1993), pp. 1–23Google Scholar; Shue, ‘Thickening Convergence’, pp. 218–19). And according to others, that inattention signals the basis of human rights in a ‘Western’ system of value, one that prioritizes individual well-being over the greater good of the community. (See e.g. Donnelly, Jack, ‘Human Rights and Asian Values: A Defense of “Western” Universalism’, The East Asian Challenge for Human Rights, ed. Bauer, Joanne R. and Bell, Daniel A. (Cambridge, 1999), pp. 60–87, at 78–9Google Scholar.)

⁷ See Tasioulas, John, ‘The Moral Reality of Human Rights’, Freedom from Poverty as a Human Rights: Who owes What to the Very Poor?, ed. Pogge, Thomas (Oxford, 2008), pp. 80, 88–95Google Scholar.

⁸ The main sources I shall be referring to are: (a) O'Neill, Onora, Towards Justice and Virtue: A Constructive Account of Practical Reasoning (Cambridge, 1996), pp. 128–36CrossRefGoogle Scholar; (b) O'Neill, Onora, ‘The Dark Side of Human Rights’, International Affairs 81 (2005), pp. 427–39CrossRefGoogle Scholar.

⁹ This thesis of logical correlativity is most famously attributed to Wesley Hohfeld, who advances it in his discussion of ‘claim-rights’, which he sees as rights ‘in the strictest sense’. See Hohfeld, Wesley, Fundamental Legal Conceptions (New Haven, 1923), pp. 36–8Google Scholar. The same idea is also implicit in Joseph Raz's influential account of rights: ‘ “X has a right” if and only if . . . an aspect of X's well-being (his interest) is a sufficient reason for holding some other person(s) to be under a duty’ (Raz, The Morality of Freedom (Oxford, 1986), p. 166).

¹⁰ O'Neill, Towards Justice and Virtue, p. 129.

¹¹ See Feinberg, Joel, Social Philosophy (Englewood Cliffs, 1973), pp. 66–7Google Scholar.

¹² O'Neill, Towards Justice and Virtue, p. 130, fn. 4.

¹³ O'Neill, Towards Justice and Virtue, pp. 130–2.

¹⁴ Maurice Cranston was the most popular early defender of this view. See Cranston, Maurice, What are Human Rights? (London, 1973), pp. 66–7Google Scholar.

¹⁵ See Shue, Basic Rights.

¹⁶ O'Neill, Towards Justice and Virtue, p. 131.

¹⁷ O'Neill, ‘The Dark Side of Human Rights’, p. 432; O'Neill, Towards Justice and Virtue, pp. 132–6.

¹⁸ O'Neill, ‘The Dark Side of Human Rights’, pp. 432–3; O'Neill, Towards Justice and Virtue, pp. 133–4.

¹⁹ The term originates in Feinberg, Social Philosophy, p. 67.

²⁰ It is unclear whether O'Neill's argument here is based on an epistemological claim (i.e. that we need institutions to help us identify a right's duty-bearers) or an ontological claim (i.e. that only institutions can make the identity of a right's duty-bearers determinate), or both. Ultimately, I don't think anything of serious importance hangs on the matter. If O'Neill is only making the epistemological claim then, it is true, there will be a sense in which welfare rights can exist prior to institutional specification, since such rights may still have ontologically determinate duty-bearers. But this theoretical possibility would be entirely irrelevant in practice, since our inability actually to identify the relevant duty-bearers in such a case would still leave us unable to confirm the right's ontological determinacy, and so unable to justifiably claim its existence. Thus, the basic thrust of O'Neill's objection remains the same on either claim.

²¹ O'Neill, Towards Justice and Virtue, p. 133.

²² It is worth briefly noting here that a right or entitlement can be what I am calling ‘unrealizable’ for a number of distinct reasons: these include its (a) unenforceability, (b) non-justiciability or (c) infeasibility. So, for instance, (a) a right may be unrealizable if there are no reliable and available means of enforcing compliance with its attendant obligations. Or, (b) it may be unrealizable because the courts and legislature are unwilling and/or unable to legally administer the right, in which case it is non-justiciable. In other circumstances, (c) the duties generated by a right may not be feasible in the present and for the foreseeable future (this is different from their being unenforceable), in which case we might reasonably question the existence of that right (For a useful discussion, see Gilabert, Pablo, ‘The Feasibility of Basic Socioeconomic Rights: A Conceptual Exploration’, The Philosophical Quarterly 59 (2009), pp. 651–81)CrossRefGoogle Scholar. In this strand of O'Neill's argument, (d) a right is deemed unrealizable not because we cannot enforce compliance with its attendant obligations, or because these are unfeasible or non-justiciable, but because we do not know who bears these obligations. Several authors have run the issues of feasibility and claimability together, most likely because, when a right is infeasible, it is also unclaimable, i.e. it has no identifiable duty-bearers (e.g. see Feinberg, Social Philosophy, pp. 66–7; Cranston, What are Human Rights?, pp. 68–9; Williams, Bernard, In the Beginning was the Deed: Realism and Moralism in Political Argument, ed. Hawthorne, Geoffrey, (Princeton, 2005), p. 64)Google Scholar. But this tendency should be resisted. This is because a right can be unclaimable but nevertheless feasible if, say, we know that it generates feasible duties but cannot yet discern who specifically bears those duties. Precisely because they fudge this distinction, it is not entirely clear whether these authors think claimability (properly understood) is an existence condition of rights.

²³ See O'Neill, Onora, Constructions of Reason: Explorations of Kant's Practical Philosophy (Cambridge, 1989), pp. 230–1Google Scholar; O'Neill, Towards Justice and Virtue, pp. 136–53.

²⁴ See e.g. Buchanan, Allen, ‘What's so Special about Rights?’, Social Philosophy and Policy 2 (1984), pp. 61–83, at 74CrossRefGoogle Scholar; O'Neill, Towards Justice and Virtue, p. 139.

²⁵ Indeed, Elizabeth Ashford interprets O'Neill as adopting this broader conception of claimability, which requires identifying ‘both the precise content of the corresponding duties and the specific agents responsible for fulfilling them’. Ashford, Elizabeth, ‘The Duties Imposed by the Human Right to Basic Necessities’, Freedom from Poverty as a Human Rights: Who owes What to the Very Poor?, ed. Pogge, Thomas (Oxford, 2008), pp. 183–218, at 214 (my emphasis)Google Scholar.

²⁶ See O'Neill, ‘The Dark Side of Human Rights’, pp. 427–39.

²⁷ I recognize that, as a Kantian, O'Neill may be unwilling to acknowledge the possibility that rights may conflict, and so would also be unwilling to admit that rights have weight. Nevertheless, even the most ardent absolutist about rights (e.g. see Shafer-Landau, Russ, ‘Specifying Absolute Rights’, The Arizona Law Review 35 (1995), pp. 209–25)Google Scholar must admit that, until the full content of a right is worked out, there are questions about the lexical priority of rights over one another (and over non-rights-based considerations) that remain open and important.

²⁸ I leave aside here some important doubts about the cogency of O'Neill's attempt to single welfare rights out for criticism by way of the distinction between primary and secondary duties. See Tasioulas, ‘The Moral Reality of Human Rights’, pp. 91–2.

²⁹ This is also how O'Neill herself understands the notion of abstraction: ‘Abstraction, taken straightforwardly, is a matter of bracketing, but not of denying, predicates that are true of the matter under discussion’ (O'Neill, Towards Justice and Virtue, p. 40).

³⁰ For a similar definition of abstract rights, see Nickel, James W., Making Sense of Human Rights, 2nd edn. (Oxford, 2007), pp. 23–4.Google Scholar Also see Raz, The Morality of Freedom, p. 184; Griffin, James, On Human Rights (Oxford, 2008), p. 50CrossRefGoogle Scholar; and Waldron, Jeremy, Liberal Rights: Collected Papers 1981–1991 (Cambridge, 1993), pp. 77–8Google Scholar.

³¹ It's worth noting here that the abstractness of a right is something different from its (i) vagueness or (ii) ambiguity, although these are also forms of indeterminacy. A right is vague if it appeals to concepts or predicates that are prone to borderline cases, i.e. cases in which they neither clearly apply nor clearly fail to apply. But not all abstract rights are vague in this sense. Moreover, not all abstract rights are ambiguous in the sense of committing homonymy, i.e. picking out categorically different objects in the way that a right to ‘fence’ can be both a right to engage in an Olympic sport and to engage in the activity of marking boundaries between properties. See Waldron's, Jeremydiscussion of vagueness, ambiguity, indeterminacy and contestability in ‘Vagueness in Law and Language: Some Philosophical Issues’, California Law Review 82 (1994), pp. 509–40CrossRefGoogle Scholar.

³² This is simply a repetition of the criticisms that O'Neill raises against welfare rights, as discussed in section II, but now applied to abstract rights more generally. Since O'Neill lauds the use of abstraction in moral reasoning elsewhere in her writings (e.g. O'Neill, Towards Justice and Virtue, ch. 2), one way to interpret my own analysis is as pointing out a tension in her views on abstraction.

³³ I should mention that O'Neill might be willing to accept the existence of abstract rights if they were thought of as merely generalized assemblages of specific and claimable rights (in the way that my right to freedom of movement might be understood as nothing more than a shorthand term for an infinite number of specific and claimable rights, e.g. to stand on my head, to move my arm, to walk outside, etc.). But this is not how abstract rights are normally understood: they are often thought to have independent justificatory force as the grounds of more specific rights, in the way just described. (See also Waldron, Liberal Rights, pp. 77–8; Raz, The Morality of Freedom, p. 169.) That prominent and important conception of abstract rights – without which we could not affirm a human right to, say, adequate nourishment, since we cannot cite specific and claimable rights to such nourishment that hold in each individual case in advance – would still be unsustainable on O'Neill's account.

³⁴ In this respect, the current article builds on Tasioulas’ response to O'Neill's claimability objection in Tasioulas, ‘The Moral Reality of Human Rights’. That said, my own response (in section IV) is less dependent on the acceptance of the interest-based theory of rights than his is.

³⁵ See the reference in n. 26 above. There is, furthermore, no principled reason that I can think of for denying that claimability, if it is a necessary feature of rights at all, is a necessary feature of both moral and legal rights (at least so long as we are talking about ‘claim-rights’ and not some other Hohfeldian category); and so in this very direct sense claimability is as much a legal concern as it is a moral one.

³⁶ See Neuman, Gerald L., ‘Human Rights and Constitutional Rights: Harmony and Dissonance’, Stanford Law Review 55 (2003), pp. 1868–9Google Scholar.

³⁷ For an instructive overview of the complex role of precedent in international law (including international human rights law), see Guillaume, Gilbert, ‘The Use of Precedent by International Judges and Arbitrators’, Journal of International Dispute Settlement 2 (2011), pp. 5–23CrossRefGoogle Scholar.

³⁸ See Neuman, ‘Human Rights and Constitutional Rights’, p. 1878.

³⁹ See e.g. Griffin, James, ‘Discrepancies between the Best Philosophical Account of Human Rights and the International Law of Human Rights’, Proceedings of the Aristotelian Society 101 (2001), pp. 1–28CrossRefGoogle Scholar.

⁴⁰ See e.g. Griffin's ‘bottom-up’ approach to human rights (Griffin, ‘Discrepancies’, pp. 29–30), Tasioulas’ concern with ‘fidelity’ to the post-1948 culture of human rights (Tasioulas, John, ‘Are Human Rights Essentially Triggers for Intervention?’, Philosophy Compass 4 (2009), pp. 938–50CrossRefGoogle Scholar), and Joseph Raz and Charles Beitz's explicit theoretical focus on the modern political ‘practice’ of human rights (e.g. Raz, Joseph, ‘Human Rights without Foundations’, The Philosophy of International Law, ed. Tasioulas, J. and Besson, S. (Oxford, 2010), esp. pp. 323–4, 334–7Google Scholar; Beitz, Charles, The Idea of Human Rights (Oxford, 2009), pp. 7–13)CrossRefGoogle Scholar.

⁴¹ See Neuman, ‘Human Rights and Constitutional Rights’, pp. 1868–9.

⁴² Note I am not here suggesting that human rights are norms that are necessarily destined for embodiment in law. For a version of this kind of claim, see Habermas, Jürgen, ‘The Concept of Human Dignity and the Realistic Utopia of Human Rights’, Metaphilosophy 41 (2009), pp. 469–70Google Scholar.

⁴³ See Feinberg, Social Philosophy, pp. 64–7.

⁴⁴ Shue, Basic Rights, e.g. p. 165, rightly emphasizes the importance of this third set of considerations in establishing the validity of any right or claim.

⁴⁵ Tasioulas, ‘The Moral Reality of Human Rights’, p. 94. Also see MacCormick, Neil, Legal Right and Social Democracy: Essays in Legal and Political Philosophy (Oxford, 1982), pp. 161–4Google Scholar, for a similar line of reasoning.

⁴⁶ Consider, for example, the widespread enthusiasm that has greeted Rawls's notion of the ‘burdens of judgment’, according to which ‘all our concepts . . . are vague and subject to hard cases’ (Rawls, John, Political Liberalism (New York, 1996), p. 56Google Scholar).

⁴⁷ Shue's discussion of how to allocate duties of assistance is highly instructive in this regard. See Shue, Basic Rights, ch. 5.

⁴⁸ This isn't to say that institutions are the sole means of specifying rights. For instance, Shue, Basic Rights, pp. 111–31, is able to say many plausible things about what the affluent owe to the global poor without referring to any given institutional framework.

⁴⁹ See Ashford, ‘Duties’, p. 215, and Gilabert, Pablo, ‘Humanist and Political Perspectives on Human Rights’, Political Theory 39 (2011), p. 457CrossRefGoogle Scholar, who make a similar point.

⁵⁰ There is a third interpretation that, I should mention, also has this virtue. According to it, claimability is indeed a necessary feature of rights. However, it can be achieved with as little as a rough idea of a right's holder(s), duty-bearer(s), content and priority. This corresponds, broadly, to the (weaker) sort of claimability requirement that we find endorsed by Nickel, Making Sense of Human Rights, pp. 30–2; Griffin, ‘Discrepancies’, pp. 107–10; and Ashford, ‘Duties’, pp. 215–17. But since it's unclear whether there is anything of real significance riding on the preservation of the term ‘claimability’ here, it's unclear how this differs from my own position, which is similarly tolerant of indeterminacy. I shall therefore leave this possibility aside.

⁵¹ The fact that the preceding observations are independently reinforced by the interest theory of rights – according to which the existence of a right can be known before one has answered the question of exactly which agents are bound by it and what is required of them (see Raz, The Morality of Freedom, pp. 184–5; Tasioulas, ‘The Moral Reality of Human Rights’, pp. 92–3) – speaks in favour of both.

⁵² See Morsink, Johannes, The Universal Declaration of Human Rights: Origins, Drafting, and Intent (Philadelphia, 2001), pp. 33–5Google Scholar. There are of course other reasons, like efficiency, for favoring generality and succinctness in the law. For instance, Jeremy Bentham famously complained of the senseless ‘multitude’ of laws prohibiting the stealing of vegetables in Georgian England, where instead of having generic statutes, one had ‘one law for one sort of vegetable, another for another’. See ‘Letter V’ in The Collected Works of Jeremy Bentham: On the Liberty of the Press, and Public Discussion, and other Legal and Political Writings for Spain and Portugal, ed. Catherine Pease-Watkin and Philip Schofield (Oxford, 2012), p. 183.

⁵³ See Morsink, The Universal Declaration of Human Rights, pp. 228–30.

⁵⁴ Article 23, UDHR.

⁵⁵ Article 21, UDHR.

⁵⁶ This is, of course, providing we see such peoples as truly isolated and not, say, as citizens of Brazil.

⁵⁷ Article 16, UDHR.

⁵⁸ One question that is raised by these examples is that of what we are to make of these purported human rights, if they are not in fact universal. Human rights are, after all, supposed to be rights possessed by all human beings, irrespective of nation, race, creed, tribe or culture. One plausible solution is to accept the possibility of two varieties of human rights. On the one hand, there are abstract and consummately universal human rights: rights that apply to all individuals in all cases, even though their deontic implications are protean and may vary (e.g. the human right to political participation). And, on the other hand, there are derivative or specific human rights: rights that are generated by the application of a universal human right to a specific (cultural and/or institutional) context, taking into account the special features of that context, but that are not themselves universal in scope (e.g. the human right to periodic and genuine elections). According to this sort of picture, many of the rights posited by international and domestic law are indeed human rights, although they are so in light of being broadly applicable specifications of universal rights, not in virtue of being universal human rights themselves. For a similar view, see Gilabert, ‘Humanist and Political Perspectives on Human Rights’, p. 445; Griffin, ‘Discrepancies’, sec. 2.8.

⁵⁹ This is what Raz and Tasioulas refer to as the ‘dynamicity of rights’. See Tasioulas, ‘The Moral Reality of Human Rights’, pp. 92–8, esp. p. 94; Raz, The Morality of Freedom, pp. 185–6.

⁶⁰ See Orentlicher, Diane F., ‘Relativism and Religion’, Human Rights as Politics and Idolatry (Princeton, 2001), p. 144Google Scholar; Joseph Raz, ‘Human Rights in the New World Order’ (DRAFT), sec. 3.

⁶¹ This parallels the justification for the allowance of a ‘margin of appreciation’ by the European Court of Human Rights in national interpretations of the ECHR among EU members. See Neuman, ‘Human Rights and Constitutional Rights’, pp. 1881–6; also Wilkins, Burleigh, ‘International Human Rights and National Discretion’, The Journal of Ethics 6 (2002), pp. 373–82CrossRefGoogle Scholar.

⁶² In writing this article, I benefited greatly from the constructive feedback of Elizabeth Ashford, Kimberley Brownlee, Roger Crisp, Pablo Gilabert, Peter Jones, Joshua Keton, James W. Nickel, Onora O'Neill, Adina Preda, Mauro Rossi, Jeremy Waldron, Daniel Weinstock, two anonymous reviewers at Utilitas, and editor Brad Hooker.