The Dam Project.: Who are the experts? A philosophical lesson from the Vajont disaster

In 1963 a huge landslide covered the Vajont valley (north-east of Italy), where one of the tallest arch dams in the world had been put in place (completed in 1959). More than 2000 people died. The locals had repeatedly warned the scientists that the sides of the valley were too fragile to hold significant impact, and publicly raised concern. The ensuing media debate surrounding issues of safety in the valley soon became manipulated for political purposes, and the important message got wasted. With the help of this case study we analyse how two types of knowledge (official science and local experience) may confront each other and why they fail to interact. We then draw some lessons concerning how the use of expert knowledge becomes effective and valuable in the context of non-expert knowledge.