The twelve lessons forming this volume were originally issued in the shape of monthly lessons, known as "The Advanced Course in Yogi Philosophy and Oriental Occultism" during a period of twelve months beginning with October 1904, and ending September 1905. We have been told, so often, that we must take certain things "on faith, " and that it was "no use bothering our minds concerning them, " but this is only a partial statement of truth, for the Intellect does give us a reliable report concerning the real nature of things.