Conspiracy theories and beliefs in such theories are not a new phenomenon of the 21st century but have existed for a long time throughout human history. However, the topic only gained increased scholarly attention since the mid-twentieth century, involving researchers from various scientific disciplines, such as psychology, anthropology, philosophy, history, political science, and sociology, to name but a few. Defining what constitutes a conspiracy theory is not straightforward, especially as the term is often used in a “pejorative sense”, with the aim to delegitimize the person believing in this theory and to end any serious discussion about the topic.