4. Modalities of a decision "based on the precautionary principle

The precautionary principle can be formulated in many different ways, but it seems possible to classify them into two categories: on the one hand, radical formulations, which systematically lead to prohibitions in situations of doubt, and, on the other, proportionate formulations, which require action but do not strictly define the modalities.

We will only briefly mention the radical versions, based on the principle of "reversal of the burden of proof", i.e. the obligation to ban any innovation until it has been proven harmless. Indeed, if we accept the above criticisms of the intrinsic limitations of the scientific approach, it becomes just as pointless to demand proof of a risk as to prove its absence. Paradoxically, radical formulations are just as positivist and reductionist as the standard model of expertise.

In this section, we will...