A father of a young family, a philosophy student who is about to graduate, a trader who is so convinced that he quits his job after 18 years. Will they enjoy their last day on earth or will they see the sun rise yet again on the 22nd of May? By now, we know the answer to that last question, but the more intriguing question is: how did people become so absorbed in their ideas? The way in which the believers admit that the idea was purely psychological is reflected in the many testimonies. How does it get that far? Sheila Marshall gives sociologists and neuroscientists the opportunity to create more context. It not only sketches the thinking pattern of a certain community, but also an image for all of us about how broader beliefs and thoughts can come about. 'Have you ever been convinced or something, beyond all doubt?'