The Yithians, more formally known “The Great Race of Yith”, are a species of body-jumping aliens.
They dwelt (or will dwell) on the planet Yith, which may be their homeworld.
The Yithians use their mind-projecting techniques to scout out the passage of time, allowing them to accurately predict their own extinction and avoid it. To do this, the mind of a specimen from a (usually sentient) species is swapped with that of a Yithian for a period of several years, so that the Yithian can record information from that time. The target specimen, if willing to cooperate, is allowed to freedom to roam libraries and communicate with other specimens until his time of return comes. The memories of living in the cone-body, however are suppressed before the specimen’s mind can return, to secure the secrets.
Because most labor is done by machines citizens have much leisure time. This mostly is used in scholarly and aesthetical pursuits. Technology progressed to a height due to the need of surviving the cataclysmic environs of the Yithian culture on Earth. Crime barely exists and legal procedures are carried out with complete respect to the criminal. Civil wars are common inside the Yithian nation, though it often fights the prehistoric civilizations around it, including the Old Ones. But more impressively a huge army is kept on hand with “camera like weapons which produced tremendous electrical effects.” This army was to defend the race from the Flying Polyps that were trapped under the Yithian cities.
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