¹ For an account of the BSE crisis, read Patrick van Zwanenberg and Erik Millstone, “‘Mad Cow Disease’ 1980s–2000: How Reassurance Undermined Precaution,” in European Environment Agency, Late Lessons from Early Warnings: The Precautionary Principle 1896– 2000, Environmental Issue Report 22 (Copenhagen, Denmark: European Environment Agency, 2001), pp. 157–67.

² A similar type of analysis, though focusing on a somewhat different set of problems, is to be found in Per Sandin, Martin Peterson, Sven Ove Hansson, Christina Rudén, and André Juthe, “Five Charges Against the Precautionary Principle,” Journal of Risk Research 5, no. 4 (2002), pp. 287–99.

³ Cass R. Sunstein, “Irreversible and Catastrophic,” Cornell Law Review 91, no. 4 (2006), pp. 841–97; available at http:\\ssrn.com/abstract=705323; and Cass R. Sunstein, Laws of Fear: Beyond the Precautionary Principle (Cambridge, England: Cambridge University Press, 2005), ch. 5.

⁴ Arcuri, “The Case for a Procedural Version of the Precautionary Principle,” in Boyer, et al., Frontiers in the Economics of Environmental Regulation.

⁵ Frank H. Knight, Risk, Uncertainty, and Profit (Chicago: University of Chicago Press, 1921), p. 233.

⁶ Kenneth Arrow and Anthony Fisher, “Environmental Preservation, Uncertainty, and Irreversibility,” Quarterly Journal of Economics 88 (May 1974), pp. 312–19. See also Anthony Fisher, John Krutilla, and Charles Cicchetti, “The Economics of Environmental Preservation: A Theoretical and Empirical Analysis,” American Economic Review 62 (September 1972), pp. 605–19; Kenneth Arrow, “Optimal Capital Policy and Irreversible Investment,” in James N. Wolfe, ed., Value, Capital and Growth: Papers in Honor of Sir John Hicks (Edinburgh: Edinburgh University Press, 1968); and Kenneth Arrow and Mordecai Kurz, “Optimal Growth with Irreversible Investment in a Ramsey Model,” Econometrica 38 (March 1970), pp. 331–44.

⁷ Similar results were found by Claude Henry, who coined the expression “irreversibility effect.” Claude Henry, “Investment Decision under Uncertainty: The Irreversibility Effect,” American Economic Review 64 (December 1974), pp. 1006–12.

⁸ Christian Gollier, Bruno Jullien, and Nicolas Treich, “Scientific Progress and Irreversibility: An Economic Interpretation of the Precautionary Principle,” Journal of Public Economics 75 (February 2000), pp. 229–53. For a systematic survey of the economic literature focusing specifically on the precautionary principle, see Christian Gollier and Nicolas Treich, “Decision-Making under Scientific Uncertainty: The Economics of the Precautionary Principle,” Journal of Risk and Uncertainty 27 (August 2003), pp. 77–103.

⁹ The authors emphasize that “environmental problems deal with the management of a limited stock of a good. Varying this stock through early consumption generates an environmental externality for future generations.” They seem to be the first to deal not only with irreversibility but also with accumulation phenomena (e.g., past emissions of CO₂ increase current exposure to greenhouse risks due to the accumulation of gas in the atmosphere). Ibid., p. 245.

¹⁰ Technological innovation may be stimulated by regulation if companies will develop better strategies to comply with regulatory requirements, and this in turn will increase societal wealth and health. For an excellent analysis of this issue, see Samuel J. Rascoff and Richard L. Revesz, “The Biases of Risk Tradeoff Analysis: Towards Parity in Environmental and Health and Safety Regulation,” University of Chicago Law Review 69 (Fall 2002), pp. 1778–80, 1809–11.

¹¹ David Freestone and Ellen Hey, “Origins and Development of the Precautionary Principle,” in David Freestone and Ellen Hey, eds., The Precautionary Principle and International Law—The Challenge of Implementation (The Hague: Kluwer Law International, 1996), p. 13.

¹² Among the most influential critics of the principle, see Cass R. Sunstein, “Beyond the Precautionary Principle,” University of Chicago Law & Economics, Olin Working Paper No. 149 (January 2003); available at http://ssrn.com/abstract=307098; Sunstein, Laws of Fear; Lucas Bergkamp, “Understanding the Precautionary Principle,” Environmental Liability 10 (2002), Part I, pp. 18–30, and Part II, pp. 67–82; Indur Goklany, The Precautionary Principle: A Critical Appraisal of Environmental Risk Assessment (Washington, D.C.: Cato Institute, 2001); and Richard B. Stewart, “Environmental Regulatory Decisionmaking under Uncertainty,” Research in Law and Economics 20 (2002), pp. 71–126.

¹³ Sunstein, Laws of Fear. This argument was initially articulated in Sunstein, “Beyond the Precautionary Principle”; it can also be found in Robert W. Hahn and Cass R. Sunstein, “The Precautionary Principle as a Basis for Decision Making,” Economists’ Voice 2, no. 2, art. 8 (2005); available at http:\\ssrn.com/abstract=721122.

¹⁴ Sunstein, Laws of Fear, p. 24

¹⁵ Ibid., p. 26.

¹⁶ Ibid., p. 33.

¹⁷ Ibid., p. 24.

¹⁸ Sunstein, “Beyond the Precautionary Principle”; Stewart, “Environmental Regulatory Decisionmaking under Uncertainty”; Hahn and Sunstein, “The Precautionary Principle as a Basis for Decision Making”; and Richard A. Posner, Catastrophe: Risk and Response (New York: Oxford University Press, 2005), ch. 3.

¹⁹ Let me stress from the outset that the following analysis will focus mostly on the concept of uncertainty; however, it should be clear that similar conclusions would hold when ambiguity and ignorance are present.

²⁰ See, e.g., Stewart, “Environmental Regulatory Decisionmaking under Uncertainty.”

²¹ Lisa Heinzerling, “Regulatory Costs of Mythic Proportions,” Yale Law Journal 107 (1998), pp. 1981–2070.

²² Martin O'Connor, Sylvie Faucheux, Géraldine Froger, Silvio Funtowicz, and Giuseppe Munda, “Emergent Complexity and Procedural Rationality: Post-Normal Science for Sustainability,” in Robert Costanza, Olman Segura, and Juan Martinez-Alier, eds., Getting Down to Earth: Practical Applications of Ecological Economics (Washington, D.C.: Island Press, 1996), pp. 233–34.

²³ John Harsanyi, “Can the Maximin Principle Serve as a Basis for Morality: A Critique of John Rawls's Theory,” American Political Science Review 69, no. 2 (June 1975), pp. 594–606.

²⁴ Kristin S. Shrader-Frechette, Risk and Rationality: Philosophical Foundations for Populist Reforms (Berkeley and Los Angeles, Calif.: University of California Press, 1991), ch. 8.

²⁵ Stephen Gardiner, “A Core Precautionary Principle,” Journal of Political Philosophy 14, no. 1 (2006), pp. 33–60; for a comment on this point, see Sunstein, “Irreversible and Catastrophic,” pp. 35–54; and Sunstein, Laws of Fear, pp. 111–15.

²⁶ Herbert Simon, “Rationality as a Process and as a Product of Thought,” American Economic Review 68, no. 2 (1978), p. 9.

²⁷ Gardiner, “A Core Precautionary Principle,” p. 57.

²⁸ For a review of the group of scholars that would endorse this position, see Kristin S. Shrader-Frechette, “Technological Risk and Small Probabilities,” Journal of Business Ethics 4 (1985), pp. 431–45.

²⁹ Max H. Bazerman, “Climate Change as a Predictable Surprise,” Harvard NOM Working Paper No. 06-03 (June 7, 2005); available at http:\\ssrn.com/abstract=785990.

³⁰ David Dembo, Ward Morehouse, and Lucinda Wykle, Abuse of Power—Social Performance of Multinational Corporations: The Case of Union Carbide (New York: New Horizon Press, 1990), pp. 89–90. See also Dan Kurzman, A Killing Wind: Inside Union Carbide and the Bhopal Catastrophe (New York: McGraw-Hill, 1987).

³¹ For a review of authors using this argument, see Sandin, et al., “Five Charges Against the Precautionary Principle,” pp. 295–96; see also Julian Morris, ed., Rethinking Risk and the Precautionary Principle (Oxford: Butterworth-Heinemann, 2000).

³² Kerstin Dressel, “The Cultural Politics of Science and Decision-Making: An Anglo-German Comparison of Risk Political Cultures—The BSE Case” (doctoral thesis, 2000); available at http:\\bse.airtime.co.uk/dressel.htm (last accessed July 31, 2006).

³³ Discussed in Wybe Th. Douma, The Precautionary Principle: Its Application in International, European and Dutch Law (doctoral thesis, 2002, unpublished), p. 230; compare EU Committee of the American Chamber of Commerce in Belgium, Position Paper on a Comprehensive Risk Analysis Process (September 9, 1999).

³⁴ Quoted in David B. Resnik, “Is the Precautionary Principle Unscientific?” Studies in History and Philosophy of Science Part C 34, no. 2 (2003), pp. 329–44.

³⁵ Henry Miller, “Letter to the Editor: The Bogus Precautionary Principle,” Wall Street Journal, March 1, 2001, p. A23, quoted in Resnik, “Is the Precautionary Principle Unscientific?”

³⁶ Resnik, “Is the Precautionary Principle Unscientific?”; Kenneth R. Foster, Paolo Vecchia, and Michael Repacholi, “Science and the Precautionary Principle,” Science 288, no. 5468 (May 12, 2000), pp. 979–81; and Sandin, et al., “Five Charges Against the Precautionary Principle,” pp. 295–96.

³⁷ Resnik, “Is the Precautionary Principle Unscientific?” p. 337.

³⁸ For a discussion of the use of animal bioassay in risk assessment, see Alan Rosenthal, George M. Gray, and John D. Graham, “Legislating Acceptable Cancer Risk from Exposure to Toxic Chemicals,” Ecology Law Quarterly 19, no. 2 (1992), pp. 269–362.

³⁹ John D. Graham, Laura Green, Marc Roberts, “In Search of Safety: Chemicals and Cancer Risk,” as reprinted in Richard L. Revesz, Foundations of Environmental Law and Policy (New York: Foundation Press, 1997). As a default position based primarily on policy considerations, the EPA requires the use of linearized multistage (LMS) models. Justice Stephen Breyer has criticized this model as being a “too conservative” method of estimating low-dose risks. By contrast, Adam Finkel has argued that this is a scientifically valid method (possibly superior to the threshold theories privileged by Breyer) that has no conservative bias; Stephen Breyer, Breaking the Vicious Circle: Toward Effective Risk Regulation (Cambridge, Mass.: Harvard University Press, 1993); Adam Finkel, “A Second Opinion on an Environmental Misdiagnosis: The Risky Prescriptions of Breaking the Vicious Circle,” New York University Environmental Law Journal 3, no. 2 (1994), pp. 295–381, available at http:\\www.law.nyu.edu/journals/envtllaw/issues/vol3/2/3nyuelj295.html; and Sheila Jasanoff, “Acceptable Evidence in a Pluralistic Society,” in Deborah G. Mayo and Rachelle D. Hollander, eds., Acceptable Evidence: Science and Value in Risk Management (New York: Oxford University Press, 1991), pp. 29–47.

⁴⁰ Pat Kane, “There's Method in the Magic,” in Jane Franklin, ed., The Politics of Risk Society (Cambridge, England: Polity Press, 1998), p. 77.

⁴¹ Sunstein, Laws of Fear, p. 35.

⁴² Sunstein, Laws of Fear; and Breyer, Breaking the Vicious Circle.

⁴³ Daniel Kahneman, Paul Slovic, and Amos Tversky, eds., Judgment Under Uncertainty: Heuristics and Biases (Cambridge, England: Cambridge University Press, 1982); Cass R. Sunstein, “Hazardous Heuristics,” University of Chicago Law & Economics, Olin Working Paper No. 165, and University of Chicago Public Law Research Paper No. 33 (October 2002); available at http:\\ssrn.com/abstract=344620; and Cass R. Sunstein, “Probability Neglect: Emotions, Worst Cases, and Law,” Yale Law Journal 112 (October 2002), pp. 61–107.

⁴⁴ Paul Slovic, “Perception of Risk,” Science 236 (April 1987), pp. 280–85; Paul Slovic, “Beyond Numbers: A Broader Perspective on Risk Perception and Risk Communication,” in Mayo and Hollander, eds., Acceptable Evidence, pp. 48–65. For an overview of the literature, see Bernd Rohrmann and Ortwin Renn, “Risk Perception Research—An Introduction,” in Ortwin Renn and Bernd Rohrmann, eds., Cross-Cultural Risk Perception: A Survey of Empirical Studies (Dordrecth, Holland: Kluwer Academic Publisher, 2000), pp. 11–54.

⁴⁵ Slovic, “Beyond Numbers,” p. 65.

⁴⁶ For a seminal work in this area, see Mary Douglas and Aaron Wildavsky, Risk and Culture: An Essay on the Selection of Technical and Environmental Dangers (Berkeley, Calif.: University of California Press, 1982); for an overview of theories, see Dan M. Kahan, Paul Slovic, Donald Braman, and John Gastil, “Fear of Democracy: A Cultural Evaluation of Sunstein on Risk,” Harvard Law Review 119 (2006), pp. 1071–1109.

⁴⁷ Kahan, et al., “Fear of Democracy,” p. 1091.

⁴⁸ Ibid., pp. 1072–73.

⁴⁹ Ortwin Renn, “Concepts of Risk: A Classification,” in Sheldon Krimsky and Dominic Golding, eds., Social Theories of Risk (Westport, Conn.: Praeger, 1992), p. 77.