On the apparent paradox of ideal theory

Journal of Political Philosophy

Volumn 17, Issue 3, 2009, Pages 332-355

  Valentini, Laura ^a  

^a UNIVERSITY COLLEGE LONDON   (United Kingdom)

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EID: 68249120569     PISSN: 09638016     EISSN: 14679760     Source Type: Journal    
DOI: 10.1111/j.1467-9760.2008.00317.x     Document Type: Article

References (150)

1. I am borrowing this broad definition of ideal theory from Sarah Williams Holtman, 'Kant, ideal theory, and the justice of exclusionary zoning', Ethics, 110 (1999), 32-58, at p. 34.
2. Onora O'Neill offers extensive discussions of the notion of idealisation in Towards Justice and Virtue (Cambridge: Cambridge University Press, 1996), pp. 39-44,
3. and 'Abstraction, idealization and ideology in ethics', Moral Philosophy and Contemporary Problems, ed. J.D.G. Evans (Cambridge: Cambridge University Press, 1987), pp. 55-69. John Rawls adopts a narrower notion of ideal theory, focusing on two idealisations in particular: full compliance and favourable conditions. In this article, I only discuss the notion of an ideal theory broadly construed, which includes, but is not limited to, Rawls's narrower definition.
4. John Rawls, A Theory of Justice (Oxford: Oxford University Press, 1999 rev. ed.), pp. 4-8 (henceforth TJ);
5. and The Law of Peoples (Cambridge, MA: Harvard University Press, 1999), pp. 4-5, 8-9 (henceforth LP).
6. Rawls, TJ, p. 125.
7. Ronald Dworkin, Sovereign Virtue: The Theory and Practice of Equality (Cambridge, MA: Harvard University Press, 2000), pp. 172 ff. (henceforth SV).
8. A recent formulation of this critique is offered by Colin Farrelly, 'Justice in ideal theory: a refutation', Political Studies, 55 (2007), 844-64.
9. See also Amartya Sen's critique of what he calls 'transcendental' theories of justice in his 'What do we want from a theory of justice?' Journal of Philosophy, 103 (2006), 215-38.
10. G.A. Cohen, 'Facts and principles', Philosophy and Public Affairs, 31 (2003), 211-45. To be more precise, Cohen does not talk about fact-sensitive and fact-insensitive normative theories, but rather about fact-sensitive and fact-insensitive normative principles (of justice in particular). Since, however, principles are the main components of theories, Cohen's distinction naturally extends to different ways of theorising about justice.
11. My discussion here also benefits from Michael Blake's distinction between ideal institutional and non-institutional theorising in 'Distributive justice, state coercion, and autonomy', Philosophy and Public Affairs, 30 (2001), 257-96, esp. at pp. 263-4, n.7,
12. and from Aaron James's distinction between practice-based and non-practice-based theorising, 'Constructing justice for existing practice: Rawls and the status quo', Philosophy and Public Affairs, 33 (2005), 281-316, at pp. 293-5.
13. Cf. Andrea Sangiovanni's somewhat wider distinction between relational and nonrelational approaches to justice in 'Global justice, reciprocity, and the state', Philosophy and Public Affairs, 35 (2007), 3-39, at pp. 5-8.
14. See also his 'Justice and the priority of politics to morality', Journal of Political Philosophy, 16 (2008), 137-64.
15. In offering this formulation in terms of power I am indebted to Aaron James's discussion in 'Power in social organization as the subject of justice', Pacific Philosophical Quarterly, 86 (2005), 25-49.
16. This approach is defended by G.A. Cohen in 'Facts and principles'. As Cohen himself remarks (p. 244, n.48), Richard Arneson seems to agree with certain aspects of his view.
17. See R.J. Arneson, 'Luck egalitarianism and prioritarianism', Ethics, 110 (2000), 339-49, p. 345.
18. Andrew Mason, 'Just constraints', British Journal of Political Science, 34 (2004), 251-68,
19. and Adam Swift, 'The value of philosophy in non-ideal circumstances', Social Theory and Practice (forthcoming 2008) also approve of this form of theorising.
20. Colin Farrelly, for instance, proposes this continuum model in 'Justice in ideal theory: a refutation'.
21. This can be taken as a generalised description of what Cohen, 'Facts and principles', p. 241, calls 'principles of regulation' which, he says, are the object of fact-sensitive theories.
22. My understanding of the distinction between theories of type (1) and (2) has benefited from many conversations with Miriam Ronzoni, who explores it in depth in 'Constructivism and the basic structure of society' (Oxford D.Phil. thesis, forthcoming 2008).
23. G. A. Cohen, 'Expensive taste rides again', Dworkin and His Critics, ed. J. Burley (Oxford: Blackwell, 2004), pp. 3-29, at p. 18.
24. Cohen, 'Facts and principles', p. 243, emphasis added.
25. For a related discussion see Miriam Ronzoni and Laura Valentini, 'On the meta-ethical status of constructivism: reflections on G.A. Cohen's "Facts and principles"', Politics, Philosophy & Economics (forthcoming).
26. So-called democratic or relational egalitarians can also be counted among the advocates of the fact-sensitive approach. See, e.g., Elizabeth Anderson, 'What is the point of equality?' Ethics, 109 (1999), 287-337,
27. and Samuel Scheffler, 'What is egalitarianism?' Philosophy and Public Affairs, 31 (2003), 5-39.
28. John Rawls, Justice as Fairness: A Restatement (Cambridge, MA: Harvard University Press, 2001), p. 41 (henceforth JFR).
29. John Rawls, Political Liberalism (New York: Columbia University Press, 1996), pp. 44 ff. (henceforth PL).
30. John Rawls, Political Liberalism, 1996, Ibid., p. 46.
31. For an early statement of this conception of justification see Rawls, TJ, pp. 506 f
32. Rawls, PL, p. 110.
33. On the divergence between individuals' priority judgements see TJ, pp. 39-40.
34. A similar description of Rawls's approach in terms of a 'public framework of thought' is offered by Sen in 'What do we want from a theory of justice?'
35. Dworkin, SV, p. 1.
36. Notice that Dworkin uses the notion of political power much more narrowly than I do. Instead of seeing it as the power members of a political community exercise over one another through the operation of their institutions, he conceives of it in terms of the influence members have over political decisions. See Dworkin, SV, ibid., p. 65 and ch. 42E
37. Dworkin, SV, Ibid., p. 4, emphasis added.
38. For a detailed taxonomy of ideal theory see Ingrid Robeyns, 'Ideal theory in theory and practice', Social Theory and Practice (forthcoming 2008).
39. See also Charles W. Mills, ' "Ideal theory" as ideology', Hypatia, 20 (2005), 165-84, esp. at pp. 166-7.
40. In 'What do we want from a theory of justice?' Amartya Sen has challenged this claim, arguing that theories of justice can also be purely comparative. Such theories tell us how different societies ought to be ranked from the viewpoint of justice, without specifying what a perfectly just society would look like. I thank Christian Barry for drawing my attention to this issue.
41. Zofia Stemplowska has recently argued in favour of a different technical definition of ideal theory, based on the particular function ideal theory is meant to perform. See her 'What's ideal about ideal theory?' Social Theory and Practice (forthcoming 2008).
42. Onora O'Neill, for instance, argues that, unlike abstractions, idealisations can (and perhaps should) be avoided. For discussion see O'Neill, Towards Justice and Virtue, pp. 39-44.
43. For scepticism about O'Neill's position see Miriam Ronzoni, 'Constructivisms: between abstraction and idealisation' (unpublished manuscript);
44. Lisa H. Schwartzman, 'Abstraction, idealization, and oppression', Metaphilosophy, 37 (2006), 565-88,
45. and Robert E. Goodin, 'Political ideals and political practice', British Journal of Political Science, 25 (1995), 37-56, esp. at pp. 40-5.
46. Rawls, TJ, pp. 118-23.
47. Rawls, TJ, Ibid., pp. 137-8.
48. Rawls, TJ, Ibid., pp. 123-5.
49. Dworkin, SV, p. 172.
50. Dworkin, SV, Ibid., pp. 66 ff.
51. For a helpful summary of Dworkin's theory to which I am indebted see Will Kymlicka, Contemporary Political Philosophy: An Introduction (Oxford: Oxford University Press, 2002), pp. 75-88.
52. Dworkin, SV, pp. 67-8.
53. Dworkin, SV, Ibid., pp. 73 ff.
54. Dworkin, SV, Ibid., pp. 147-61 and 161-2 respectively.
55. Dworkin, SV, Ibid., pp. 162-80.
56. Of course, what counts as 'humanly achievable' is a controversial, largely speculative, matter.
57. In so saying, I am not suggesting that a theory of justice cannot be 'incentive-compatible'. Indeed, one of the most discussed features of Rawls's difference principle is its attempted incentive-compatibility. Recall that the principle justifies inequalities so long as they are needed to benefit the worse-off, and these include inequalities generated to incentivise talented people to make occupational choices that maximise productivity. Compatibility of a theory of justice with a certain degree of human self-interestedness seems necessary given that justice, as a value, makes sense only because human beings are partly self-interested, as opposed to angelically altruistic. The point I am making in the main text is that, once the principles of justice have been defined (whatever their degree of incentive-compatibility) each individual in society is assumed to do her part in upholding them. For a critique of Rawls's incentives argument for inequality, see G.A. Cohen, If You're an Egalitarian, How Come You're So Rich? (Cambridge, MA: Harvard University Press, 2000), esp. ch. 8. I am grateful to Christian List for bringing this issue to my attention.
58. For a discussion see Raymond Geuss, 'Neither history nor praxis', Outside Ethics (Princeton, NJ: Princeton University Press, 2005), pp. 29-39.
59. For a helpful account of the 'psychological, sociological, and epistemological' constraints to be taken into account by a theory that aims to be practically effective see Joseph H. Carens, 'Realistic and idealistic approaches to the ethics of migration', International Migration Review, 30 (1996), 156-70.
60. On related issues, see also Juha Räikkä, 'The feasibility condition in political theory', The Journal of Political Philosophy, 6 (1998), 27-40;
61. Sanjay Reddy, 'The role of apparent constraints in normative reasoning: a methodological statement and application to global justice', The Journal of Ethics, 9 (2005), 119-25,
62. and Robert E. Goodin's discussion of what he calls the 'accessibility critique' of ideals in 'Political ideals and political practice', pp. 39-40.
63. Immanuel Kant, 'On the common saying: this may be true in theory, but it does not apply in practice', Kant's Political Writings, ed. H.S. Reiss (Cambridge: Cambridge University Press, 1970), pp. 61-92, at p. 61.
64. This point is very well made by O'Neill in 'Abstraction, idealization and ideology in ethics', p. 59.
65. See, e.g., the complex argument through which Sarah Williams Holtman shows how Kantian ideal theory might offer guidance in establishing the legitimacy of real-world policies in 'Kant, ideal theory, and the justice of exclusionary zoning'.
66. Kant, 'On the common saying: this may be true in theory, but it does not apply in practice', p. 61.
67. At points, Annette Baier does seem to advance such a radical critique to normative theorising in 'Theory and reflective practices', Postures of The Mind: Essays on Mind and Morals (London: Methuen, 1985), pp. 207-27.
68. Annette Baier 'Theory and reflective practices', Postures of The Mind: Essays on Mind and Morals, 1985, Ibid., p. 225.
69. For a sustained discussion of this difficulty see Michael Phillips, 'Reflections on the transition from ideal to non-ideal theory', Noûs, 19 (1985), 551-70.
70. For similar examples see Michael Phillips, 'Reflections on the transition from ideal to non-ideal theory', Nous, 19 (1985) Ibid., pp. 559-60.
71. O'Neill, Towards Justice and Virtue, p. 41.
72. Notice, however, that O'Neill's overall critique of idealisation does not so much focus on the issue of guidance, but rather on the difficulty of justifying idealised premises without appealing to controversial metaphysical claims. For O'Neill's remarks on issues of guidance see 'Abstraction, idealization and ideology in ethics'.
73. Baier, 'Theory and reflective practices', p. 210, emphasis added.
74. I point this out because critics often fail to distinguish between GC2 and GC3.
75. Thomas McCarthy, 'Political philosophy and racial injustice: from normative to critical theory', Pragmatism, Critique, Judgement, eds S. Benhabib and N. Fraser (Cambridge, MA: MIT Press, 2004), pp. 147-70, at p. 165, emphasis original.
76. For a similar claim on the difficulty in bridging the gap between ideal and nonideal theory see Philllips, 'Reflections on the transition from ideal to non-ideal theory', p. 551.
77. Joel Feinberg also offers some sceptical remarks on the guidance capacity of Rawls's ideal theory, particularly with reference to the case of civil disobedience, in 'Duty and obligation in the non-ideal world', Journal of Philosophy, 70 (1973), 263-75.
78. Mills, ' "Ideal theory" as ideology'.
79. My argument is thus limited in scope. I only discuss deontological liberal approaches to justice and do not consider whether the 'guidance critique' would also apply to other types of outlooks. For instance, as David Grewal and Gabriel Wollner have (independently) pointed out to me, consequentialist theories of justice might be immune to the challenges discussed here.
80. Rawls, JFR, p. 66.
81. For a general discussion of racial and sexual discrimination containing helpful methodological reflections on the relation between 'ideals' and 'social realities' see Richard A. Wasserstrom, 'Racism, sexism and preferential treatment: an approach to the topics', Contemporary Political Philosophy: An Anthology, eds R. Goodin and P. Pettit (Oxford: Blackwell, 1997), pp. 579-604.
82. Susan Moller Okin, Justice, Gender, and the Family (New York: Basic Books, 1989), esp. pp. 89-109.
83. Rawls, JFR, pp. 162-8.
84. Rawls, JFR, Ibid., p. 167.
85. This point is defended and discussed in Thomas W. Pogge, 'On the site of distributive justice: reflections on Cohen and Murphy', Philosophy and Public Affairs, 29 (2000), 137-69, esp. at p. 165.
86. Cf. G.A. Cohen, 'Where the action is: on the site of distributive justice', Philosophy and Public Affairs, 26 (1997), 3-30,
87. and Liam B. Murphy, 'Institutions and the demands of justice', Philosophy and Public Affairs, 27 (1998), 251-91, who criticise the basic structural (political) focus of Rawls's theory. As I note later, here I do not discuss this critique.
88. Rawls seems to be more radical on this point, suggesting that how to best realise women's equality 'in particular historical conditions is not for political philosophy to decide', Rawls, JFR, p. 167. Here I am making the weaker claim that this is not for political philosophy alone to decide.
89. Rawls, TJ, p. 327.
90. Rawls, TJ, p. 327. Ibid.
91. In particular, Rawls thinks that violations of the difference principle are the most difficult injustices to detect, while violations of the first principle and 'blatant violations' of fair equality of opportunity are more likely to be 'obvious to all', Rawls, TJ, Ibid., pp. 326-7.
92. I am grateful to an anonymous referee for raising this concern.
93. I wish to thank Miriam Ronzoni for bringing this point to my attention. Ronzoni offers a sustained defence of Rawls's basic structural approach in 'Constructivism and the basic structure of society'. See also Pogge, 'On the site of distributive justice: reflections on Cohen and Murphy'.
94. Roland Pierik and Ingrid Robeyns, 'Resources versus capabilities: social endowments in egalitarian theory27, Political Studies, 55 (200729, 133-52, at p. 141, emphasis original.
95. For a critique of Dworkin's methodology see also Philip Abbott, 'Review of Sovereign Virtue', Rhetoric & Public Affairs, 4 (2001), 576-8.
96. Pierik and Robeyns, 'Resources versus capabilities', p. 142.
97. Dworkin, SV, p. 165.
98. In spite of her critique of Dworkin, Robeyns ('Ideal theory in theory and practice') now recognizes the legitimacy of such idealisations for the purpose of designing an ideal theory of justice.
99. Critics sometimes recognize this point, but lament that, apart from sporadic remarks (for instance, Dworkin says 'If proper civil rights laws were enacted and enforced, the influence of prejudice . . . would wane', SV, pp. 345-6), Dworkin seldom discusses the question of how to bring socially generated inequalities to an end directly in connection with his ideal theory. See Pierik and Robeyns, 'Resources versus capabilities', pp. 143-6
100. and Robeyns, 'Ideal theory in theory and practice'. This may very well be true but, as I already noticed, the absence of explicit discussion does not mean that a fruitful discussion could not be developed on the basis of Dworkin's theory.
101. Dworkin, SV, chs 11 and 12.
102. For discussion see Thomas Nagel, 'Equal treatment and compensatory discrimination', Equality and Preferential Treatment, eds M. Cohen, T. Nagel and T. Scanlon (Princeton, NJ: Princeton University Press, 1977), pp. 3-18.
103. Though this accusation is probably unfair in the case of Dworkin, who devotes about half of Sovereign Virtue to the 'practice' of equality.
104. Rawls, LP, pp. 3, 10, emphasis original.
105. In Rawls's words (Rawls, LP, Ibid., p. 6, n.7), as a realistic utopia the Law of Peoples 'sets limits to the reasonable exercise of power'.
106. For Rawls's list see Rawls, LP, Ibid., p. 37.
107. Rawls, LP, Ibid., p. 4.
108. More precisely, burdened societies are societies which 'lack the political and cultural traditions, the human capital and know-how, and, often, the material and technological resources needed to be well-ordered'. Rawls, LP, Ibid., p. 106.
109. Allen Buchanan, 'Rawls's Law of Peoples: rules for a vanished Westphalian world', Ethics, 110 (2000), 697-721, esp. at pp. 716-20.
110. Simon Caney, 'Cosmopolitanism and the Law of Peoples', Journal of Political Philosophy, 10 (2002), 95-123, at pp. 118-9.
111. Rawls, LP, p. 89.
112. Thomas W. Pogge, 'Moral universalism and global economic justice', Politics, Philosophy & Economics, 1 (2002), 29-58, esp. at pp. 46-9,
113. reprinted in Pogge, World Poverty and Human Rights (Cambridge: Polity, 2002), ch. 4.
114. For an overall critical appraisal of The Law of Peoples see also Pogge's 'Critical study: Rawls on international justice', Philosophical Quarterly, 51 (2001), 246-53.
115. On this see, e.g., David Singh Grewal, 'Network power and globalization', Ethics and International Affairs, 17 (2003), 89-98;
116. Darrell Moellendorf, 'The World Trade Organization and egalitarian justice', Metaphilosophy, 36 (2005), 145-62;
117. and Richard H. Steinberg, 'In the shadow of law or power? Consensus-based bargaining and outcomes in the GATT/WTO', International Organizations, 56 (2002), 339-74.
118. Thomas W. Pogge, ' "Assisting" the global poor', The Ethics of Assistance: Morality and the Distant Needy, ed. D.K. Chatterjee (Cambridge: Cambridge University Press, 2004), pp. 260-88.
119. Notice that Rawls is not unaware that existing liberal states are far less well-ordered than his 'peoples' (LP, pp. 48, 53), yet he seems to ignore this in his discussion of non-ideal theory.
120. Will Kymlicka, Multicultural Citizenship: A Liberal Theory of Minority Rights (Oxford: Oxford University Press, 1995) (hereafter MC).
121. Will Kymlicka, 'Do we need a liberal theory of minority rights? Reply to Carens, Young, Parekh and Forst', Constellations, 4 (1997), 72-87, at p. 75.
122. Kymlicka, MC, pp. 214, n.11, 109.
123. Kymlicka, MC, Ibid., p. 152, emphases original.
124. Kymlicka, MC, Ibid., ch. 8.
125. Kymlicka, MC, Ibid., pp. 165, 169.
126. See, e.g., Brian Barry, Culture and Equality (Cambridge: Polity Press, 20031), ch. 4.
127. See also Chandran Kukathas, 'Multiculturalism as fairness: Will Kymlicka's Multicultural Citizenship', Journal of Political Philosophy, 5 (1997), 406-27, at p. 420,
128. and Geoffrey Brahm Levey, 'Equality, autonomy, and cultural rights', Political Theory, 25 (1997), 215-48, esp. at pp. 227 ff.
129. For a sustained critical discussion of the limitations of Kymlicka's ideal theoretic approach to which I am indebted see Adrian Favell, 'Applied political philosophy at the Rubicon: Will Kymlicka's multicultural citizenship', Ethical Theory and Moral Practice, 1 (1998), 255-78.
130. Kymlicka, MC, p. 165.
131. As Cécile Laborde has suggested to me, this clearly emerges from the fact that Kymlicka defends national minorities because they provide a context of choice. This implicitly assumes minorities to be already liberal (just). Otherwise, how could they be a context of choice?
132. Kymlicka, MC, p. 164.
133. As Zofia Stemplowska has helpfully pointed out to me, right-libertarians would disagree with this claim, arguing that egalitarians like Rawls and Dworkin have an implausibly idealised conception of the state. For right-libertarians the complex state apparatus necessary to realise egalitarian policies would inevitably fall prey to corruption and power abuses, thus hindering, rather than promoting, the pursuit of justice. My argument in this article is entirely internal to liberal egalitarianism and thus does not respond to this libertarian critique.
134. Rawls, LP, p. 42, n.52.
135. Simon Caney, 'Cosmopolitanism and the Law of Peoples', p. 118,
136. and Thomas W. Pogge, 'The incoherence between Rawls's theories of justice', Fordham Law Review, 72 (2004), 1739-59, at p. 1751. Pogge offers a detailed critical analysis of the structural differences between Rawls's domestic and international theories of justice, which has informed my own discussion here. In particular, he argues that while Rawls's domestic theory is three-tiered and institutional, his international theory is two-tiered and interactional. In Pogge's view, these structural asymmetries explain much of what is problematic about The Law of Peoples. For further discussion of Pogge's view in the relation to the argument presented here, see footnote 106 of this article.
137. Interestingly, some scholars have emphasised this aspect of Rawls's theory to defend it against cosmopolitan objections. In their view, since Rawls's principles are meant to apply in 'ideal theory'-where no power abuses occur-they should not be objected to on the grounds that they are misguiding (or unhelpful) in real-world circumstances. Obviously, this defence of The Law of Peoples only succeeds if we reject the claim that any sound normative theory should be action-guiding. For this line of argument see, e.g., Stephen Macedo, 'What self-governing peoples owe to one another: universalism, diversity, and The Law of Peoples', Fordham Law Review, 72 (2004), 1721-38, esp. at p. 1727
138. and Samuel Freeman, 'The Law of Peoples, social cooperation, human rights, and distributive justice', Social Philosophy and Policy, 23 (2006), 29-68, at pp. 32-3.
139. I borrow this expression from Phillips, 'Reflections on the transition from ideal to non-ideal theory'.
140. Buchanan, 'Rawls's Law of Peoples: rules for a vanished Westphalian world'.
141. Interestingly, this is acknowledged even by advocates of non-ideal theory, for instance by Mills, '"Ideal theory" as ideology', p. 171, when he says that 'nonideal theory can and does appeal to an ideal'.
142. In connection with this point, Ingrid Robeyns and Miriam Ronzoni have suggested to me that a dimension along which we may distinguish between good and bad idealisations is their flexibility, that is the extent to which they constitute an integral part of a theory. The more idealisations are integral to a theory, the harder it is for the theory to adjust to its 'real-world' object and to provide valuable tools for studying it. Robeyns further discusses how to distinguish between good and bad idealisations in 'Ideal theory in theory and practice'.
143. I owe this point to a very helpful discussion with Christian List.
144. O'Neill, Towards Justice and Virtue, p. 41.
145. Pogge's distinction between two-tiered and three-tiered theories (introduced at footnote 98 of this article) helps explain this aspect of Rawls's approach to international justice. In particular, Pogge claims that while Rawls's domestic theory of justice is three-tiered-the parties in the original position (1) select principles (2) to govern the basic structure of society (3)-the 'Law of Peoples' is two-tiered: the representatives of peoples (1) select principles for guiding peoples' conduct (2). In light of our discussion, we might say that while three-tiered theories ensure a separation between the justification of principles (1 and 2) and their application to the subject of justice (3), this does not happen with two-tiered ones, such as the Law of Peoples. This is why idealisations that would be appropriate at the level of its justification end up characterizing the subjects to which Rawls's theory of international justice is meant to apply. See Pogge, 'The incoherence between Rawls's theories of justice'.
146. On related themes see Lea L. Ypi, 'Getting it backwards: ideal and non-ideal in recent debates on global justice' (unpublished manuscript).
147. O'Neill also briefly remarks on the use of idealisations in theoretical, as opposed to practical, reasoning, in Towards Justice and Virtue, pp. 41-2.
148. I am grateful to Robert E. Goodin for suggesting these examples.
149. See Daniel M. Hausman, 'Philosophy of economics', The Stanford Encyclopedia of Philosophy, ed. Edward N. Zalta (Summer 2006 edn); available at: http://plato.stanford.edu/ archives/sum2006/entries/economics/.
150. In recent years, however, behavioural economists have considered more empirically informed behavioural assumptions and investigated how these affect standard results in economic theory.