Team:SDU-Denmark/Precaution Studies

Studies on the Precautionary Principle


The problem with precaution and risk is that one never seems to have a certain knowledge about the outcome of an event. On everyday basis it does not seem to be a big issue: “maybe I will get wet if I leave the umbrella at home”. But when it comes to the decisions we have to make as a society then it is a different story: e.g. what will the consequences be if one was to allow more use of pesticides? When the consequences can not be known for certain then there is room for potentially big catastrophes - maybe all our water supply will be contaminated, which could lead to hormonal imbalances or something worse and unforeseen.


When considering the options, one should ask at least three questions: “What possible outcomes could the action have? How good (or bad) are these different outcomes? At what likelihood would these different outcomes occur?” The problem is that especially the last question possesses unknown factors. What we, as a society, seem to lack is a way of rationally deciding which action to take when factors are unknown. One also needs to be able to distinguish between which possible risks are important to take under consideration and which are not. It is not rational to take all possible risks under equal consideration - there seems to be some possible risks that are so unlikely that one should not take them too seriously, e.g. when transforming E. coli to synthesize spider silk, the impact on global warming should not be a problem to take into consideration.


In our field of synthetic biology we find the possible consequences in the lab and their probability are mathematically decided. But on that note there is a clear difference between the probability for the hypothesis or theory to be correct and the probability threshold we decide by when it comes to risk assessments.

Take for example a hypothesis stating that “the chemical substance X is dangerous and leads to cancer”. For this hypothesis to be accepted into the scientific corpus it needs to fulfill different - and more - requirements than it needs for the society to ban substance X on the base of precaution. Because if they knew it could potentially lead to cancer, they would be scared and why should they risk it? The epistemic values are simply different when it comes to scientific theories compared to the qualities which we value by when it comes to risks. Normally, when it comes to risk assessment it is more fatal to accept a technology or new substance which leads to undesired consequences than to accept a false hypothesis into a scientific theory.


The Precautionary Principle

This is called “The Precautionary Principle”, which has many different definitions but in essence it means: if an activity has potential harms by a certain degree, precautionary measures should be taken even if the likelihood of the harms occurring have not been scientifically confirmed. Other definitions could be: “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” Principle 15 of the 1992 Rio Declaration on Environment and Development or “When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause-and-effect relationships are not fully established scientifically” Wingspread Statement on the Precautionary Principle. One study shows that one bacteria, which produces the bacteriocin leugudin, outcouncours the MRSA in vitro, which are great results, but from these results we do not just treat MRSA patients with the outcouncouring bacteria because we do not know the possible consequences of that action. It could potentially lead to even greater infection or problems for the patient or society.

This leads to the conclusion that even though the essence of the Precautionary Principle is intuitive for most, the precise definition and the influence of the principle is still debated.


The Precautionary Principle can be defined by three parts: The Meta-Precautionary Principle, the “Tripod” and Proportionality STEEL, D. 2014. Philosophy and the precautionary principle, Cambridge University Press.. The combination of these is what makes the Precautionary Principle a good tool for decision-making. The Meta-Precautionary Principle places restrictions on which types of decision-rules should be applied. The decision-rules in question are not to allow inaction because of scientific uncertainty - one should never be paralyzed by a lack of knowledge when facing serious threats STEEL, D. 2014. Philosophy and the precautionary principle, Cambridge University Press.. The “Tripod” part is actually three parts in itself: The epistemological condition, the damage condition and the remedy or action that are recommended CARTER, J. A. & PETERSON, M. 2015. On the Epistemology of the Precautionary Principle. Erkenntnis, 80, 1-13.. The epistemological condition is a proposition that stands in reference to the damage condition. The damage condition is the possible harm(s), which can happen as consequences of the activity in question. The epistemological condition is then the evidence one has for the probability that the damage will occur. The connection between the epistemological condition and the damage condition is most often thought of as a causal connection.


The three conditions in the Tripod are also the case dependent part of the Precautionary Principle. The Tripod is therefore the most flexible part of the Precautionary Principle and the different cases then require different versions of the Precautionary Principle: “[...] any statement according to which satisfying a specific [epistemological condition] and [damage condition] is sufficient to justify a specific [remedy]” STEEL, D. 2014. Philosophy and the precautionary principle, Cambridge University Press.. Which version to choose is specified by the constraints from the Meta-Precautionary Principle.

The last part, proportionality, is a contextualist-based idea. More precise it is the idea that the level of precautionary measures taken corresponds to both the probability and the damage. It is similar to the economic thought of cost and efficiency - if the cost is high, then the efficiency should be as well.


The three elements are the essential parts of the Precautionary Principle when it functions like a decision rule. But it is important to be aware that the Precautionary Principle can function as a procedural requirement, where the Meta-Precautionary Principle is highlighted or as an epistemic rule STEEL, D. 2014. Philosophy and the precautionary principle, Cambridge University Press.. We will here focus on the Precautionary Principle as a decision rule composed of the Meta-Precautionary Principle, the Tripod and Proportionality.


How does it work?

One thing is understanding the essence of the Precautionary Principle, but when it comes to how it should be applied there are different explications of it. Some interpretations focus on catastrophes (Catastrophic Precautionary Principle), for some it is a maximin rule and others again see it as a minimax regret.


The Catastrophic Precautionary Principle is proposed by Hartzell-Nichols HARTZELL-NICHOLS, L. 2012. Precaution and solar radiation management. Ethics, Policy & Environment, 15, 158-171. and states: “Appropriate precautionary measures should be taken against threats of catastrophe” with definitions and restrictions to follow. Some of his requirements are very similar to the parts of the Precautionary Principle that we have already defined: e.g. “A precise probability of a threat of harm is not needed to warrant taking precautionary measures so long as the mechanism by which the threat would be realized is well understood and the conditions for the function of the mechanism are accumulating”. The requirement meets the demand imposed by the Meta-Precautionary Principle, which stated that one should not be paralyzed from taking action by lacking scientific evidence. The demand about consistency is also present in one of his requirements.


The Catastrophic Precautionary Principle then compiles fine with the Precautionary Principle we already have defined and it then seems to be a version of the Precautionary Principle. A version because the damage and epistemological conditions, that are parts of the Tripod, are specified. The damage condition is set to be only “catastrophe” and the epistemological condition to be “the mechanism by which the threat would be realized is well understood and the conditions for the function of the mechanism are accumulating”. As a positive effect, the Catastrophic Precautionary Principle is more well-defined and easier to apply but it is also more limited, where the Precautionary Principle normally is thought of as having a broader range than catastrophes - e.g. genetically modified organisms (GMO’s).


The maximin rule comes from a different background than the Precautionary Principle, i.e. political philosophy rather than bioethics. It has then been transformed for a use in bioethics. The maximin rule is an expression for choosing the action that has the smallest chances of resulting in ‘worst case’ scenarios. It is almost always very restricted and one of the most central restrictions is ‘pure uncertainty’ STEEL, D. 2014. Philosophy and the precautionary principle, Cambridge University Press.. By pure uncertainty is meant “a total lack of information about the probabilities of the relevant possible scenarios” - then the maximin rule is applied to make sure that one assures the highest minimum of good. The proposal for which conditions has to be satisfied before recommending precaution are STEEL, D. 2014. Philosophy and the precautionary principle, Cambridge University Press.:

  1. Pure uncertainty
  2. There is no possible scenario wherein catastrophe occurs when the precaution is taken
  3. Taking the precaution achieves results that are close to the best case that could have been achieved
  4. If the precaution is not taken, then catastrophe will occur

These conditions are quite strict, which limits the use of the maximin rule, e.g. it is rare that we have complete uncertainty (1) when discussing the Precautionary Principle. The problem is more often incomplete knowledge.


The minimax regret is originally an economic principle but has been proposed as an explication of the Precautionary Principle by Chrisholm and Clarke CHISHOLM, A. & CLARKE, H. 1993. Fair principles for sustainable development. Natural Resource Management and the Precautionary Principle (ed. Edward Dommen), Edward Elgar Publishing, 109-122.. The minimax regret helps finding what action (i.e. precaution or no precaution) in a given case that has the least difference between its result and the best possible result that could be obtained in the case. If there is no difference between the first action and its result and the best possible result, then there is no regret and it is therefore the action to choose. It can be clarified by showing in the two tables.


Table one.

Case 1Case 2Case 3
PrecautionExpenses that occur when implementing the precaution (e)Expenses that occur when implementing the precaution (e)Expenses that occur when implementing the precaution and catastrophe (e + c)
No precautionCatastrophe (c)No risk of catastrophe, but damage will occur (d)Catastrophe (c)

If one then supposes that the catastrophe is more severe than the expenses, which then are more than the damage (If one sees it as absolute numbers of costs, then: c>e>d). Then the table with the regrets will look like this:


Table two.

Case 1Case 2>Case 3
PrecautionNo regrets (0)The amount of the difference between the expenses and the damage (e - d)The amount of expenses (e)
No precautionThe amount of the difference between the catastrophe and expenses (c - e)No regrets (0)No regrets (0)

The recommendation will then be to select the action (i.e. precaution or no precaution) that has the smallest amount of regret in the case in question. Then, if we stick to the fixed presumptions (c>e>d) then the actions to choose are precaution in case 1 and no precaution in case 2 and 3. The presumptions are dependent of the specific cases.


The problem with the minimax regret is that it treats the epistemological and the damage condition as quantitative, where the Precautionary Principle has to be applicable to qualitative measures as well. The two conditions have to be thought of as quantitative for the terms of ‘difference’ between them makes sense STEEL, D. 2014. Philosophy and the precautionary principle, Cambridge University Press..