The book “Merchants of Doubt” addresses the connections among scientific research, politics and the role that media play in building connections between technical knowledge and common knowledge. Science historian at the University of San Diego and co-author of the book, Naomi Oreskes explains to Emanuele Bompan and Paolo Savoia that science is a historical process. “Scientific activity is a rather complicated affair – she says – It is a human activity in which progress and expert judgment is fundamental. What we call scientific knowledge is the result of collaboration, research, proof, and consensus, however partial, from a community of experts that formulate informed judgments, though they are still subjective, on the information they gather, and eventually draw conclusions about their meaning”. Dealing with science, media usually grant equal space to two opinions that are not equally supported by scientific evidence. “Journalists – Naomi Oreskes assesses – should stop and reflect for a moment on what it means to be objective”.