This book also provides insight into the origin of most of the excesses and deviances "modern"
If we manage to essentially seize this book (which is confirmed by observation, in-depth study of the mechanisms and science related to politics, physics, economics, etc. as well as by psychic experiences and especially spiritual), this is a good way to refute the modern as atheists, nihilists, and other scientists. This also shows the depth and wisdom, and intellectual scope of spiritual traditions.
It is focused on metaphysics, so it takes a little familiar with the technical vocabulary to own this knowledge to better navigate.
If the price was not so high (about 9-10e) for a number of pages so small, this book deserved a five star by its content (concise but very rich).