The prevalence of conspiracy theories is astounding. Almost every historical event or observable phenomenon seems to have at least one conspiracy theory associated with it. Authors have proposed several reasons why human beings are so drawn to conspiracy theories.

To account for variations in observation. Anyone who studies history seriously knows that there is rarely a completely reliable, authoritative version of the facts surrounding any notable occurrence. The tidbits of inconsistency upon which most conspiracy theories rely occur constantly in connection with any activity we undertake. It's only when important activities are closely scrutinized that these details receive close attention. In other words, it's natural for people to believe that there should be no inconsistency in legitimate activities. So if we observe an inconsistency, we take that alone as evidence that the intuitive explanation must be flawed and we should search for a more complicated answer.

As entertainment. Real life is boring. We constantly seek to embellish it, whether formally through media such as motion pictures or fictional literature, or informally through the exaggeration of our personal experiences. It's more exciting to believe that strange lights in the sky are visiting aliens and not an airliner's landing lights. As astounding as the moon landings were, it's even more astounding to suppose that the entire thing was falsified.

To seem intelligent. Conspiracy theories are often much more elaborate than what's commonly believed about something. And they usually require the listener to expand his understanding to accept the possibility of a conspiracy. Those who casually examine photographs of the lunar landings are impressed when they are led to discover discrepancies. This inflates the ego and gives one the impression that he is smarter than the dozens who look at the same photographs and see nothing special.

To be "on the inside." The conspiracist fancies himself to be elite, to be privy to secret information that few others have.

To express distrust for authority. Americans especially take delight in distrusting authority, particularly governments.