A Precautionary-Principled Approach Towards Uncertain Risks: Review and Decision-Theoretic Elaboration

Precautionary judgment, decision, and action are needed in situations involving serious uncertain risk. Examples are mountain climbing, nanotechnology, global warming, and international terrorism. The history of the Precautionary Principle (PP) shows that its proponents and opponents have different appraisals of probabilistic risk analysis. However, modern ‘risk governance’ and precautionary safety management seem to be converging into a balance of useful substance and feasible procedure. In this paper, the PP is unfolded as a three-way principle for risk assessment, decision-making, and risk control. For an integrative circumscription of the PP, ten key issues are identified. These are discussed one by one, whereby ‘rational’ precautionary decision-making is particularly illustrated via the concrete example of a railway bomb alarm. It is argued that a substantive-analytical framework is indispensable, that a decision-theoretic perspective may offer useful guidance, that the PP is a rational (survival) rather than a normative (ideological) principle, that the need to avoid false negatives versus false positives may well differ among distinct policy domains, and that precautionary ‘pessimism’ should stimulate towards improved, multi-sided control of uncertain risks. Concluding questions are answered and research suggestions are formulated.