Aleister Crowley was among the first Europeans to study, practice and teach Yoga. These lectures set forth some of Crowley's conclusions after a lifelong philosophical investigation. The first series of lectures is entitled 'Yoga for Yahoos.' The elements of Yoga are introduced, examined and demystified with a view to extracting the practical essence of Yoga doctrine. Yoga is also correlated with astrology and the Qabalah. The second series is entitled 'Yoga for Yellowbellies.' Here Crowley weaves Yoga into a conceptual framework the encompasses Western philosophy, magick and mathematical physics. All of these lectures are approached with humor, wit and a minimum of jargon.