Scientific progress does not consist solely in the discovery of new truths; it also includes the exposure of mistakes. Often errors turned out to be necessary before the truth could finally be discovered. The history of science is thus not only a history of valuable finds, but also one of vagaries, gropings, and failures. There are some mistakes, however, which scarcely belong to the long series of honourable scientific errors and carry a wholly different meaning: these are the mistakes made by scientists or pseudo-scientists who, driven by the will-to-power, have abused science for the temporary achievement of their ambitions.