This book introduced me to some of the most infamous charlatans in history: Aleister Crowley, Madame Blavatsky, Charles Manson, to name a few. Scammers and fraudsters abound, but so do believers. Amazingly, in today's age of easy access to most anything, cults still manage to thrive.
* In 1985, a dear aunt left us a set of books on the Supernatural. Published in the mid-seventies, the books are dated by today's standards, and sketchy even back then--an encyclopaedia/The Sun hybrid. Over the years, the titles got lost, and those which remained had broken spines and missing pages, a result of persistent re-readings. I've always wanted to recapture the fascination I had for these books, so when I saw a mint set available on eBay in 2018, I bought it.
But oh my, such irony at play here. The main reason my aunt and her family left us these books was because they were migrating to the States. They were migrating to the States because of a cult that had initially allied itself with the Catholic church, long since debunked, and had, over a period of two years, become so enamored with the cult's levitations-on-demand, its seance-like meetings, the parents felt it was right to uproot all five children, teenagers, all, in one go.
I'm not a good judge of validity, but I used this for a research project. It provides lots of illuminating information and certainly deepened my understanding of both modern and ancient cults.