Barry Taff put together a book called "Aliens Above Ghosts Below" that is pretty deep. Barry is a parapsychologist with 4000 cases under his belt including the famous case made into a movie "The Entity" back in 80s. He also has the nickname "Superman" because he has the ability to look at someone and "see" ailments, cancers etc on someone.
The book begins by defining ghost and hauntings, apparitions and poltergeist and supported these basic theories with a multitude of examples from Barry's experience showing the reader that these are not cut and dry.
The second part of the book dealt with aliens showing essentially the same phenomena in both areas of study. Barry tackles "holography perception" and finally tying everything together with the chapter on the PSI-UFO Connection.
He tries to tie some of the paranormal phenomena like "Zero Point Energy" with propulsion in UFOs. Other concepts that the typical descriptions of aliens with the generic looking big heads and lack of detail is because they may be "drones" of sort. The length of time to travel (even for them) is decades and maybe aren't alive so to speak.
Anyway, crazy concepts that made for interesting reading.
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