In other instances common everyday objects look like UFO's because of some odd quirk in the human mind. A star or planet that has been in the sky every day of the observer's life suddenly "takes off at high speed on a highly erratic flight path." Or a vapor trail from a high-flying jet--seen a hundred times before by the observer--becomes a flying saucer. Some psychologists explain such aberrations as being akin to the crowd behavior mechanism at work in the "bobby-sox craze." Teen-agers don't know why they squeal and swoon when their current fetish sways and croons. Yet everybody else is squealing, so they squeal too. Maybe that great comedian, Jimmy Durante, has the answer: "Everybody wants to get into the act." I am convinced that a certain percentage of UFO reports come from people who see flying saucers because others report seeing them. But this "will to see" may have deeper roots, almost religious implications, for some people. Consciously or unconsciously, they want UFO's to be real and to come from outer space. These individuals, frightened perhaps by threats of atomic destruction, or lesser fears--who knows what--act as if nothing that men can do can save the earth. Instead, they seek salvation from outer space, on the forlorn premise that flying saucer men, by their very existence, are wiser and more advanced than we. Such people may reason that a race of men capable of interplanetary travel have lived well into, or through, an atomic age. They have survived and they can tell us their secret of survival. Maybe the threat of an atomic war unified their planet and allowed them to divert their war effort to one of social and technical advancement. To such people a searchlight on a cloud or a bright star is an interplanetary spaceship. If all the UFO reports that the Air Force has received in the past eight years could be put in this "psychological quirk" category, Project Blue Book would never have been organized. It is another class of reports that causes the Air Force to remain interested in UFO's. This class of reports are called "Unknowns." In determining the identity of a UFO, the project based its method of operation on a well-known psychological premise. This premise is that to get a reaction from one of the senses there must be a stimulus. If you think you see a UFO you must have seen something. Pure hallucinations are extremely rare. For anything flying in the air the stimulus could be anything that is normally seen in the air. Balloons, airplanes, and astronomical bodies are the commoner stimuli. Birds and insects are common also, but usually are seen at such close range that they are nearly always recognized. Infrequently observed things, such as sundogs, mirages, huge fireballs, and a host of other unusual flying objects, are also known stimuli.