The relationship between science and democracy has become a much-debated issue. In recent years, we have even seen an exponential growth in literature on the subject. No doubt, the interest has partly been justified by the concern of public opinion over the technological repercussions of scientific research. Moreover, there are scientific theories that, if they were accepted, would allegedly imply the adoption of policies that have wide social consequences, as well as a rethinking of deeply-rooted habits on the part of the citizens. These considerations alone allow us to understand the reasons for the interest in the, at times troublesome, relationships between science and public opinion which characterize democratic societies.