The MoD estimate that between 5% and 10% of UFO sightings remain UFOs (ie,unidentified flying objects) after investigation. Most can easily be explained as Chinese lanterns, flocks of birds, aircraft and meterological phenomena. But why do UFOs have such a hold on the imagination? There are basically two explanations. There is the Extraterrestrial Hypothesis (ETH) which holds that we really are being visited by aliens and there is the Psychosocial Hypothesis (PSH) which sees the whole UFO phenonemna as a form of modern folkore. This latter view is particularly popular among UFO researchers in the United Kingdom, such as David Clarke, Hilary Evans, the editors of Magonia magazine and many of the contributors to Fortean Times magazine. It is also popular in France since the publication in 1977 of a book written by Michel Monnerie, Et si les ovnis n'existaient pas? (What if UFOs do not exist?).
UFOlogists claim that the psychosocial hypothesis is occasionally confused with aggressive anti-ETH debunking, but that there is an important difference in that the PSH researcher sees UFOs as an interesting subject that is worthy of serious study, even if it is approached in a sceptical way.READ MORE
"Rather than simply refuting the ETH, therefore, the skeptical response is better formulated as an alternative hypothesis, what I will call the psychocultural hypothesis (PCH). The elements of the PCH are nothing new, and have been part of the standard skeptical response to ETH claims for years, but compiling these elements into a cohesive hypothesis allows us to compare the ETH and the PCH to see which one better fits the available evidence." READ MORE
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ABOUT UFO PSYCHO_SOCIAL HYPOTHESIS, here is the complete Michael Sheiser paper..!