The author, a Sanskrit scholar from South Africa, has selected 108 gems from the Upanishadic mine and strung them into a fascinating array. The selections have been arranged under suitable headings in an attempt to systematize the thought of the Upanishads.
Anything that is secret and mysterious in these systems of yoga should be at once rejected. The best guide in life is strength. In religion, as in all other matters, discard everything that weakens you, have nothing to do with it.
-Swami Vivekananda