5. Legal value

The inclusion of a new principle in the legal system is never an insignificant act. It reveals new requirements or questions that are not adequately addressed by the existing normative system. The recent irruption of the precautionary principle into positive law follows this path, and is explained as much by the need to regulate the fearsome effects likely to be generated by the uncertainties linked to the development of modern science, as by the absence of legal instruments capable of fulfilling this role .