“Apparitions: Tulpas, Ghosts, Fairies, and even Stranger Things” by Malcolm Smith
"One in ten people claim to have encountered a ghost, yet science refuses to acknowledge their existence. However, it turns out that ghosts are by no means the only, or most mysterious of apparitions. Now, an author with a background in science has sought to uncover the parameters of this bewildering field. In this, he has adopted three principals: 1. to first seek a mundane explanation 2. not accept anything until it has been confirmed by further data, and 3. not to discard any item, but to file it away in case something similar appears later. In this manner, he documents the little known phenomenon of apparitions which can be shown to result from the mind of a third party. From there he moves to apparitions of the living, then to standard ghosts and hauntings, before delving into far more profound phenomena: elves and fairies, plus a variety of even weirder apparitions, some of which are truly terrifying, and others benevolent. These remarkable phenomena are all fully documented, and by the time you finish this book, you will find it hard to reject the conclusion that there exists a whole parallel world of immaterial entities, which is only on rare occasions perceptible to our senses."
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