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Monday, May 26, 2014

Fear of Principles? A Cautionary Defense of the Precautionary Principle

Draft submitted to Mind&Society, journal. Do not quote without permission. For any comment or question, write to:

Should fear guide our actions and governments’ political decisions? A leitmotiv of common sense is that emotions are tricky, they blur our rational capacity of estimating utilities in order to plan action and thus they should be banned from any account of our rational expectations. Yet, the way in which our judgments are biased by emotional dispositions may sometimes make us end up with better choices than pure rational choices. For example, a huge literature has shown the universality of our risk-aversion and loss-aversion (Tversky and Kahneman, 1974; Kahneman 2011). These universal features don’t harm the evolution of human society. Rather, they explain the emergence of a variety of different complex (and fit!) behaviors[1]. In this paper, I would like to challenge the prejudicial idea that fear of loss should not guide our behavior at all and, especially, our collective behavior when it takes the shape of a principle of general loss-aversion, as in the case of the Precautionary Principle. In particular, I will discuss Cass Sunstein’s rejection of this principle on the basis of its incoherence by arguing that Sunstein’s criticism based on human cognitive biases misses the target of the principle. I will then argue for an ethical defense of the principle on the basis of a new vision of our moral imperatives towards the future and a different, non evidential, concern for potential catastrophic events.

What sort of principle?

The Precautionary Principle (PP in the following) is the more and more referred to in debates relating to environmental and health risks. It appeared for the first time in public debates around ecological issues in Germany in the Sixties and was rapidly adopted by ecologists especially in northern European countries. It began to be alluded to, at least implicitly, in international declarations such as the Stockholm declaration of the United Nations Environment Program (UNEP) in 1972[2]. In 1982, The World Charter of Nature, sponsored by 34 “developing” countries was adopted by the United Nations. An open reference to the PP is made for the first time in this text at a global level. It is interesting to read through the text, because it shows very clearly the new philosophy of nature that underlies the endorsement of the principle. The charter was modeled on the UN declaration of Human Rights and structured in five principles and a series of recommendations. The preamble to the principles states that the General Assembly, aware that: “(a) Mankind is a part of nature and life depends on the uninterrupted functioning of natural systems which ensure the supply of energy and nutrients, and (b) Civilization is rooted in nature, which has shaped human culture and influenced all artistic and scientific achievement, and living in harmony with nature gives man the best opportunities for the development of his creativity, and for rest and recreation” and convinced that: “(a) Every form of life is unique, warranting respect regardless of its worth to man, and, to accord other organisms such recognition, man must be guided by a moral code of action, (b)  Man can alter nature and exhaust natural resources by his action or its consequences and, therefore, must fully recognize the urgency of maintaining the stability and quality of nature and of conserving natural resources”, declares that: 1. Nature shall be respected and its essential processes shall not be impaired.
In 1987, the Montreal Protocol on Substances that Deplete the Ozone Layer, made the first explicit reference to a “precautionary approach” to the problem of the ozone layer. The PP took its first globally accepted definition in 1992, at the Rio Earth Summit, on of the major United Nations conferences on environmental issues, whose outcome was a Declaration on Environment and Development structured around 27 principles. The 15th principle is the following:

In order to protect the environment, the precautionary approach shall be widely applied by States according to their capabilities. Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation.

Further international developments of the PP can be found in the 1997 Kyoto Protocol, an international agreement related to the United Nation Framework Convention on Climate Change, which acknowledged responsibilities of developed countries for the high levels of GHG emissions and set an international agenda for monitoring and reducing emissions around the world.
In Europe, the PP has been integrated into the Lisbon Treaty, in the second paragraph of the article 191:

Union policy on the environment shall aim at a high level of protection taking into account the diversity of situations in the various regions of the Union. It shall be based on the precautionary principle and on the principles that preventive action should be taken, that environmental damage should as a priority be rectified at source and that the polluter should pay.

The precautionary principle enables rapid response in the face of a possible danger to human, animal or plant health, or to protect the environment. In particular, where scientific data do not permit a complete evaluation of the risk, recourse to PP may, for example, be used
to stop distribution or order withdrawal from the market of products likely to be hazardous.

The European philosophical roots of the principle

The idea of the possibility of environmental risks at global scale related to the awesome power of modern science and technology became a mainstream theme in the European ecological thinking, especially in Germany, in the mid Seventies. The vorsogeprinzip[3] became part of the conceptual tool kit of environmentalists in Germany, especially around the issue of acid rain  and clean air. It was also on line with a general trend of modernization of the country that should match new challenges like globalization, environmental management and the protection of global commons such as air, water, etc. In 1970, a first draft of new clean air legislation in Germany made direct reference to the idea of vorsoge. Literally, the verb Vorbeugen is commonly used in medicine and means “to bend beforehand” so that to reduce the risk of being broken. The political atmosphere that encouraged the emergence of the idea of a social responsibility in protecting the future of environmental commons was the German social democratic administration aiming at including environmental policies as part of the project of a fairer society[4]. The concept though bore a certain ambiguity among different interpretation and aims. Many authors point to a number of possible lines along which the appeal to the principle can be interpreted. It contains at least the ideas of: preventative anticipation; safeguarding of ecological space; proportionality of response; duty of care; promoting the cause of intrinsic natural rights; and paying for past ecological damage. All these concepts are evoked and included in various formulations of the principle and leave room for different applications and political uses of the principle. However, in the late Seventies, the work of the German philosopher Hans Jonas contributed to a clearer definition of the ethical reasons that underlie the principle.

Jonas and the Prinzip Verantwortung

In 1979, Hans Jonas published a book Das Prinzip Veratnwortung, later translated into English under the title: The Imperative of Responsibility. His main idea is that the new alliance between global capitalism and technology creates possibilities of action for human beings that require a wholly new ethical reflection. Many of the worries that the previous formulations of the vorsogeprinzip raised in the political discussions and the many possible interpretations of the principle were due to a lack of precise understanding of the requirements of a new ethics for the future of mankind. Jonas’ contribution may be considered the philosophical foundation of the PP. Without taking into account the “ethical turn” that Jonas puts forward, many aspects of the PP as well as its apparent incoherence - that Cass Sunstein stresses in his book[5] -  are very difficult to explain. Jonas gave voice to a diffused idea that we have entered a new era in which the intervention of humanity on nature can bring about not only irreversible harm, like global catastrophes, but irreversible transformations of the metaphysics of nature and humanity. What is at stake today is not only the destiny of humanity, but the very conception of what “being human” is and means. We can do things that make us being no longer humans, we can act in such a way as to radically change the nature of nature. That is the novelty that sustain the PP and the new responsibilities we have as actors that can modify in an unprecedented way the deep ontological intuitions we have about being human. Ethics has always dealt with human action and responsibility in a fixed natural context. Today, technologically-mediated human action can modify the environment in such a way that we cannot consider nature anymore as a neutral environment that is the theater of our actions. Nature is the target and the object of our actions whose causal consequences are incomparable to what we have seen up to now. A new form of responsibility that takes into account these potential irreversible consequences has to be at the center ethics today. Traditionally, ethics, has dealt with questions that concerned the immediate environment of action: “Treat others as you would want them to treat you”, or “Subordinate your own good to the common good”, whereas the causal consequences of human actions today make them having a potential impact on the whole universe. Jonas then presents a new categorical imperative, echoing Kant’s anti-utilitarian ethics, in the following forms: “Act so that the effects of your action are compatible with the permanence of genuine human life”, or: “Act so that the effects of your actions won’t destroy the future possibility of such a genuine human life” or else: “Include in you own choice today the future integrity of the humankind”. As for Kant’s categorical imperative, the form of knowledge required in order to be able to recognize the truthfulness of these principles is not of the same order of scientific knowledge. Ethical competence, according to Kant[6] doesn’t require any empirical knowledge and any special expertise. Anyone can acquire a moral competence: “Because in moral concerns human reason can easily be brought to a high degree of correctness and completeness, even in the commonest understanding, while on the contrary in its theoretic but pure use it is wholly dialectical”. In this sense, the new ethics put forward by Jonas doesn’t depend on the acknowledgment of new scientific facts, but on a new order of responsibilities that humans must endorse towards themselves and the survival of the natural world.
An aspect of this new ethics, according to Jonas, is that of taking into consideration the future as and not only the present as a moral dimension. When we consider future forecasting in order to take decisions today, we must adopt the principles above and, for example, prefer a less optimal outcome today if this means a better outcome for the survival of future generations.
Many commitments are implied by this imperative. First of all that we want to preserve human life in its known form, and thus exclude any futurological idea of post-humanity. Second, that we have duties toward the future generations that can be more compelling than the duties we have towards our own present. Third, that we acknowledge duties also towards non-human entities, such as water, air, etc. All these implications of the new ethics of responsibility that underlies the PP can be discussed and challenged. But, surprisingly, the angle of attack of the PP doesn’t privilege at all the ethical discussion. Rather, it focuses on the “rationality” or the “compatibility with science” of the principle, as it was obvious that an ethical principle should be justified by empirical evidence.
In the following, I will discuss Cass Sunstein’s attack to PP, together with other criticisms, and will try to argue that the target to the criticism is inappropriate and it is based on a deep misunderstanding of two main dimensions:

1. The ethical novelty of the principle
2. The statistical interpretation of the so-called “ruin-problems” or catastrophes.

Sustein’s argument fails to take into account both dimensions, by avoiding the discussion of the Kantian dimension of the PP (that is in deep opposition with any utilitarian approach to ethics) and by confusing the forecasting problem posed by the principle with classical statistical problems (hence the reference to probability biases) instead of a very special class of problems that have been defined in the recent literature as “ruin-problems”[7].

Five so-called “biases” of the PP

Cass Sunstein criticizes and rejects the PP, at least it its strongest form of requiring regulation of activities even if it cannot be shown that those activities are likely to produce significant harms on the basis of different arguments, one of which raises the question of its rationality. According to Sunstein, the PP is influenced by at least five well-known psychological biases that are very well studies in social psychology and behavioral economics:

1.     Loss aversion: according to Prospect Theory[8] people tend to be loss averse, that is, they consider more undesirable a loss from the status quo than a potential gain. In the case of PP, it means that people focus on the possible losses of a certain risky situation instead of appreciate the potential advantages that are inevitably lost by the introduction of the regulations.
2.     The myth of a Benevolent Nature: in the perception of risks, people impute more responsibility to human beings than to nature in potential harm. Nature is perceived as passive, benevolent and harmonious, while human intervention is seen as a cause of imbalance and loss of equilibrium. According to Sunstein, defenders of PP endorse this vision of nature that is not evidence-based. He brings about examples and case - like the one of man-made vs. natural made chemicals[9] - that show that human-made products may be far less toxic that nature-made ones.
3.     The availability heuristics: as largely shown in the psychological literature on heuristics and biases, people tend to be influenced by the cognitive availability of a certain risk to judge its probability. More familiar, salient or easily retrievable risks will be considered more probable than less available ones.
4.     Probability neglect: another well confirmed bias of the human mind is the tendency to miscalculate or underconsider probability. In emotionally charged situations, people tend to overestimate the probability of harm or of success. In the case of PP, it is clearly the probability of harm that, according to Sunstein, is overestimated.
5.     System neglect: Sunstein reports a rich psychological literature about the failure of most people to understand the systemic effects of a certain policy, while focusing only on one or few variables and being unable to see the causal cascade among the many parts involved in a system. PP is victim also of this neglect, because it focuses on risks in a part of the system without considering the overall trade-off of the intervention within the whole system.

First of all, it is unclear in Sunstein’s argument to understand who is the target of his criticisms, that is, who is affected by all these psychological biases. The policy makers who endorse the PP? Citizens who support it? Or the PP itself? The rhetoric varies between these different interpretations. Examples of these shifts of meaning can be found in the following statements: “Sometimes the precautionary principle operates by incorporating the belief that nature is essentially benign”[10], and: “People will be closely attuned to the losses produced by any newly introduced risk, or any aggravation of existing risks, but far less concerned with the benefits that are foregone as a result of regulation”[11] or elsewhere: “In fact many of those who endorse the principle seem to be especially concerned about new technologies”[12]. Who is then the target of Sunstein’s criticism? Policy makers? The general public opinion? The “operations” of the PP itself, as the PP was an acting agent? I think that these ambiguities show a deep misunderstanding of the level at which the results of social psychology behavioral economics should be applied. Sunstein mentions a rich experimental literature, but no evidence at all that the policy makers in Europe or around the world have been victims of these biases and neglects. Decisions in policy-making settings are not taken in the same form than decisions in everyday settings. People are asked to give reasons for a political decision or a regulatory intervention, and usually evidence-based decisions are highly appreciated. So, one could reasonably think that decisions are taken by taking into consideration these biases. If it is not the case, then, the burden of the proof rests on Professor Sunstein.
The second option is that the target of his criticism is the people in general and the public opinion. If it is so, then, another, different argument is needed in order to claim that what people think and fear, if it is biased by rational standards, should not be considered as a legitimate source of insight for policy making. We are not talking here of cases of massive irrationality or paranoid contagion, whose spreading should be avoided. We are talking here of universal psychological biases that no evidence can correct and that - given that they belong to human natural cognitive asset - have not prevented humanity to develop and survive. Prospect Theory, that is mentioned by Sunstein, is not a “bias”: it is, according to its inventors, a normative theory about human behavior; more precisely, an alternative to the homo oeconomicus, that even economists should consider in order to come out with better predictions and more accurate descriptions of human action.
More broadly, the question of the minimum standards of rationality that should be imposed to the citizens in order to participate in public life is an ancient debate that divides those who think that democracy should be based of political egalitarianism and opponents to this idea[13]. There is a tension in liberal democracies between political equality (one person, one vote) and political quality (not all points of view have the same weight to take wise decisions). One of the major problems of mature democracies is that of bridging the gap between competence and political participation. To what extent citizens must be competent? To what extent their judgments and opinions should be considered all equal? Sunstein’s invocation of cognitive biases goes with the standard complaints about democracy today that people are too ignorant, too uninformed to express a wise opinion, therefore their judgment can be manipulated and the overall objective value of the expression of their opinions be harmed. But is it so? Is this a justified complaint? Should the judgment of the many imply a certain level of rationality or probabilistic expertise in order to be taken into consideration? Should we get rid of “emotionally charged” expressions of preferences, affections, fears and commitment to deep values (like for example that of “respecting the environment” or “not eating animals”) when we assess the “rationality” of the public opinion? What sort of democracy is that envisaged by Sunstein, where our everyday understanding of our relationship with our environment and our future should be mediated by the readings of the fanciest results in behavioral economics? A true liberal democratic regulatory policy should be able to take into account values and different points of views, even about probability, without being so self assured about its epistemic superiority. Does it make any sense to ask whether Gandhi was right or wrong about his philosophy of nature given the import of his political action and the consequent democratic improvement for the whole world of India’s liberation? Could the alleged superiority of Cambridge-based techno-science in the last century over Gandhi pre-modern philosophy of nature[14] have been invoked to justify a change in policy making in India? If Sunstein’s five biases apply to citizens’ beliefs, then the burden of the proof that a better democratic action needs unbiased psychological subjects rests again on Professor Sunstein.
As for the third option, that is, that the PP is in itself biased, it is hard to figure out what exactly means that an ethical principle is biased and how psychological biases apply to international declarations.

Risk management vs. dealing with Black Swans

Precaution is different from prevention because it deals with potential risks instead of known risks. Yet, the notion of “potential risk” is quite obscure. Does it mean that the probability of the occurrence of these risks is unknown? Or does it mean that the impact of these risks is difficult, or even impossible, to anticipate? Here lies all the ambiguity of the PP, and, indeed, its difficult application as a risk management tool. Clearly, when risks are known, probabilistic risk management is sufficient to deal with potential harmful technological innovations. Take the case of the use of nuclear energy and the installation of new nuclear power plants. It raises strong emotional reactions among many people. But, as Bar-Yam, Read and Taleb (2014) say: “because of the known statistical structure of most of its problems and the absence of systemic consequences at small enough scales, at such scales the problem is better left to risk management than to PP”[15]. For a coherent application of the PP, it is essential thus, to distinguish it from a tool for risk prevention. The PP doesn’t deal with rare or unlikely events, it doesn’t rest on our cognitive failures in assessing probability distributions, nor it is a declaration of public paranoia. The PP deals with a very specific classes of events that are just not predictable, but thinkable, that is ruin-problems, or catastrophes. Catastrophes are notoriously black swans, to use the expression introduced to the large audience by the statistician and trader Nassim Nicholas Taleb[16]. A black swan is a highly improbable, hard to predict, rare event that has an enormous, disruptive impact on a system. Such extreme events are outliers, that is, they don’t lie on a Gaussian curve: their distribution is not normal. We can’t calculate the odds of a black swan, we cannot just predict it. Its probabilities, according to Taleb, are invariant to scale hence do not drop fast enough for the consequences to have a weak expected impact. Complex systems such as the techno-capitalist systems that drive our societies have scalable distributions of events. In these complex systems, rare, extreme “winner-take-all the effects” event are likely to be found. The probability distribution that contains a black swan has a fat tail, that is, the sum of the probabilities of all events will be dominated by a single one whose impact is incomparable with all the other ones. The penetration of technology within natural systems makes nature and biosphere part of these modern complex systems.
The PP deals with these kinds of events that, in such complex systems are likely to occur: ruin-events that, if they occur, are no-return events. I can survive ten times to attempts to poison me, but this doesn’t say anything about the probability that I will survive to the eleventh attempt to poison me. Rather, I may have become more fragile because of the exposure of the previous attempts. The risk of an environmental catastrophe is neither sustainable nor predictable. We have to live with and try to become more responsible and more robust to its possible occurrence. For example, diversity and redundancy are strategies that made of the evolved natural world a very robust system. Exercising the PP against the reduction of diversity and redundancy, for example of agricultural crops, may be a wise way of making us more robust to a possible radical systemic change induced by the continuous introduction of GMO in agriculture.
The PP thus cannot be neither criticized nor interpreted through the lens of a consequentialist ethics based on an estimate of the trade-offs of different probability distributions. And I agree with Sunstein about the ambiguity of some formulations of the PP that introduce this trade-off dimension. For example, the formulation in the Maastricht Treaty was the following: “The absence of certainties, given the current state of scientific and technological knowledge, must not delay the adoption of effective and proportionate preventive measures aimed at forestalling a risk of grave and irreversible damage to the environment at an economic acceptable cost”. But of course, this formulation in incoherent, because, if the risk is a major catastrophe, there is no trade-off with the “acceptable costs” to avoid it. Effectiveness, commensurability and “reasonable costs” are not the vocabulary of the unknown.


The PP introduces an ethical, normative principle for dealing with an uncertain future, where, given the complexity and interconnectedness of the natural and social systems in which we live, catastrophic black swans are more likely to occur. It introduces a future-oriented ethics by stating that the future of humankind should be part of our concerns in each choice. It introduces a bias towards the negative outcomes, that is, given the non-sustainability of a catastrophic outcome, being aware that it may happen, makes a lot of sense. It doesn’t help us in forecasting catastrophic events, but, by teaching us to fear them and to incorporate their possibility in our everyday thinking about our actions, it guides us to become more robust to them.
Indeed, we should not fear fear too much. Sometimes fear can make us stronger and wiser.

[1] Cf. Brennan, T. and Lo, A., 2011, “The Origin of Behavior”, Quarterly Journal of Finance 1: 55–108.
[2] Cf.
[3] Cf. S. Bohemer-Christiansen: “The Precautionary Principle in Germany” T. O’Riordan and J. Cameron (1994) Interpreting the Precautionary Principle, EarthScan Publishing.
[4] Cf. ibidem, p. 35.
[5] Cf. C Sunstein (2005) Laws of Fear: Beyond the Precautionary Principle, Cambridge University Press.
[6] Cf. I. Kant, 1785 Fundamental Principles of the Metaphysics of Morals, translated into English by Thomas Kingsmill Abbott.
[7] Cf. Y. Bar-Yam, R. Read, N. N. Taleb (2014): “The Precautionary Principle”; J. P. Dupuy “The Precautionary Principle and Enlightened Doomsaying: Rational Choice before
the Apocalypse.” Occasion: Interdisciplinary Studies in the Humanities 1, no. 1 (October 15, 2009),
[8] Cf. D. Kahneman, A. Tversky (1979) “Prospect Theory: An Analysis of Decision under Risk” Econometrica, 2, vol. 47, pp. 263-292; D. Kahneman (2011) Thinking, fast and slow, Allen Lane, New York.
[9] Actually, he mentions cases discussed in Paul Slovic’s work on risk perception. Cf. P. Slovic (1987) “Perception of Risk”, Science, 236, 4799, pp. 280-285.
[10] Cf. Sunstein (2003) on line at: , p.29.
[11] Cf. ibidem, p. 27.
[12] Cf. ibidem, p. 29.
[13] Cf. J. Stuart Mill (1861) On Representative Government; J. Dewey (1916) Democracy and Education, MacMillan, New York. For a recent discussion of the tension in liberal democracies between political quality and political equality, see D. Estlund (2009) Democratic Authority, Princeton University Press.
[14] For a recent account of Gandhi’s philosophy of nature, see A. Bilgrami (2014) Secularism, Identity and Enchantment, Harvard University Press.
[15] Cf.
[16] Cf. N.N. Taleb (2007) The Black Swan, Random House.