Conspiracy theories are, essentially, Wild Mass Guessing, Headscratchers, and Fanon Discontinuity (in the sense of maintaining that something didn't happen according to the way "official" sources said it did) applied to Real Life. Like all memes, conspiracy theories mutate and interbreed almost too fast for humans to track. Any of the theories and sub-theories mentioned below can be, and in all likelihood has been, combined with any or all of the others by at least one person. Don't be surprised if the theory raises more questions than the original incident in the first place. The only thing such theories prove, if anything, is that we're all too human.note
It is important to distinguish a Conspiracy Theory from a regular theory about a conspiracy. A conspiracy is merely a plan by more than one person to commit a crime, and a theory about it could be made. However, it is different from a Conspiracy Theory, as a Conspiracy Theory explicitly means a fringe theory which purports that events, either in the news or in history, are not as we understand them but really the work of secret cabals of cunning conspirators acting for malicious ends, from merely getting rich to propagating an ideology up to and including world domination.
One very easy way to debunk many of these theories, especially the big ones, is through the use of Occam's Razor: eventually, the postulates you have to accept in order to believe the theory reach improbable or impractical lengths. A tenable conspiracy theory has to overcome at least ten hurdles:
- The "cover story" must explain the event it's covering up well enough to endure all examination by media, law enforcement, or other concerned partiesnote .
- Every conspirator must have a perfect understanding of the cover story. Discrepancies could lead to the truth coming out.
- Every conspirator must have a means of contacting every other conspirator in complete privacy.
- Every conspirator must be willing to go to any lengths to keep the secret, and must abandon any notion of gaining fame, wealth, legal indemnity, or other benefits by revealing the conspiracy.
- Every piece of physical evidence must be destroyed, or placed in a secure location with incorruptible guardians. Forever.
- Anyone who discovers evidence (and is not part of the conspiracy) must be blackmailed, bribed, killed, or discredited. Which, in every case, will require a cover-up of its own.
- Anyone who might discover evidence must be monitored in some untraceable fashion for as long as they are a danger.
- Members of the conspiracy must have access to the hardware, money, and other resources they will need to do all these things, and their access to such resources must be either secret or justified in the public eye.
- No member of the conspiracy can be allowed to reveal it, so they must be in a position to silence any defector — yet each must trust the others not to misuse the power to kill or discredit them for any reason other than violation of the conspiracy. And they must never be tempted to misuse that power themselves.
- Lastly, there must be some reason that they are failing to silence the Conspiracy Theorist. Unless, of course, letting the theorist talk is just part of the cover-up.
Examples:(Before you start reading, it's worth noting that Rationalwiki has an article on a phenomenon they dub "Crank Magnetism", which is the curious tendency of people with bonkers ideas to develop or start believing in other, equally bonkers ideas; People who believe one conspiracy theory, for example, have a noted tendency to also believe other conspiracy theories, or even non-conspiracy-but-still-bonkers things such as bigotry or science denial. You're going to see a lot of this.)
- #-G: 9/11, Aliens, Disasters, Disinformation, Famous People, Guns
- H-N: Health; History, Monuments, and Ancient Civilizations; Homosexuals; Jews/Israel; John F. Kennedy's assassination; Law and Enforcement; Media; New World Order (NWO)/Secret Societies
- O-Z: Race and Immigration, Religion and Apocalyptica, Science and Technology, Sports, Tax Protestor Arguments, Wars, Weather and the Atmosphere
- Other: Other, Parodies, Actual Conspiracies