A and B arrange to meet behind C's back to gain an advantage. The simple definition of a conspiracy makes it clear that such agreements are completely self-evident in the world of business and politics, as well as in everyday life and especially in love life. Just as natural are therefore also the suspicions and suppositions about possible conspiracies, thus conspiracy theories. In order to counter doubts and disbelief about the official individual perpetrator of the murder of John F. Kennedy, the CIA for the first time converted the neutral, functional expression "conspiracy theory" into a combat term of psychological warfare. Since then, critics of official, state announcements have been labelled as "conspiracy theorists" and as fundamentally dubious, subversive to the state and following only commercial interests. "Conspiracy theory" is the discourse shutdown-argument par excellence, even if conspiracy facts continue to appear almost daily.