They form the basis of television shows and movies, they are the subject of serious discussion on the worldwide web. Conventions are held on everything from UFOs to the true identity of Jack the Ripper, from the assassination of John Kennedy to the proof of the existences of shadow governments headed by the Elders of Zion, the Freemasons, the Illuminati or the Trilateral Commission. The problem is that what seems to be nonsense to one is perfectly logical to another. And as we have seen in Folklore Studies issues of belief have nothing to do with the presumed sophistication of believers. Dismissing conspiracy theories out of hand ignores the wide range of responses that accompany conspiratorial thinking, and it conceals a central flaw as well.
Conspiracy is a criminal act which carries criminal penalties in many societies.
Failed conspiracies have often been documented historically. Part of the answer lies in Christiansen's observation about the addition of skepticism to contemporary worldview, which raises the subject of ethos, or source credibility. In rhetoric, ethos was a means of persuasion. For Aristotle, ethos was based on the character of the speaker. An ethical speaker had certain traits that made him a reliable source.