In Modern Magick I described why I thought the Hermetic Order of the Golden Dawn was important. Imagine a simple hourglass: The sand in the top half represents the  forms of occultism known in the West during the middle to late 19th century, ranging from ceremonial magick to Paganism. They were filled with differences and yet some occultists conceived that there was a hidden, underlying, unitary basis. At the central point, all of those systems merged into a complex but coherent system. That system spread out, as represented by the sand in the bottom half of the hourglass, influencing directly and indirectly virtually all forms of occultism and spirituality in the West as they exist