Colin Wilson brings an excellent conversational tone to "The Occult." Despite the fact that Wilson seems to have included virtually every pre-1970 seer, philosopher, adept, alchemist, prophet, soothsayer, necromancer and sorcerer, the book never seems poorly organized or disjointed. This is a testament to Wilson's writing style. Although by its very nature superficial, "The Occult" comes across as a conversation about the subject with a well-versed, highly-educated and rather witty enthusiast. As such, you will likely have as much fun reading it as I have. This is probably the most readable book on the topic, and a fine place to start if you're new to this.
Despite its' breadth, however, "The Occult" has one fatal flaw, and that is Wilson's inability to truly weigh competing points of view. For example, while Wilson provides rather lively portraits of Caligostro, Nostradamus, Mesmer, Pythagoras and the like, he uncritically reprints sensationalistic stories about them. Any historian of Greek philosophy can tell you that the stories Wilson shares regarding Pythagoras are most likely fiction, and any Freemason can correct Wilson's misconceptions about the Masons in his section on Caligostro. (Freemasonry is NOT a religion, despite Wilson's claims).
Still, this book deserves much praise. The Tarot is here, but so is the I Ching. Crowley is here, but so is Zen. The Kabbalah is here, but so are the Masons. And so on. While casting his net wide may open him up to charges of being a dillentant, it also saves this from being yet another collection of ghost stories and pseudo-myth. Don't buy this book because Halloween is coming. Buy it if you have ever cared about mystery, religion, philosophy, or spiritualism. You probably won't like everything about "The Occult" but I think you will be glad that you have read it and will probably want to read it again.