Before and beyond the precautionary principle: epistemology of uncertainty in science and law.

The precautionary principle has become, in European regulation of science and technology, a general principle for the protection of the health of human beings, animals, plants, and the environment. It requires that "[w]here 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". By focusing on situations of scientific uncertainty where data are lacking, insufficient, or inconclusive, the principle introduced a shift from a neutral legal attitude towards science to a bias in favor of safety, and a shift from the paradigm of science certain and objective to the awareness that the legal regulation of science involves decisions about values and interests. Implementation of the precautionary principle is highly variable. A crucial question still needs to be answered regarding the assumption that scientific certainty is a 'normal' characteristic of scientific knowledge. The relationship between technoscience and society has moved into a situation where uncertain knowledge is the rule. From this perspective, a more general framework for a democratic governance of science is needed. In democratic society, science may still have a special authoritative voice, but it cannot be the ultimate word on decisions that only the broader society may make. Therefore, the precautionary model of scientific regulation needs to be informed by an 'extended participatory model' of the relationship between science and society.