The model of the inner and outer cosmos created in Samkhya worked so well that the later schools of yoga adopted it with very little change. The Classical Yoga model changed the emphasis of the practice, but left the model virtually untouched. The Tantric school kept the twenty-four principles of Samkhya, but discovered that the Samkhya yogis stopped their inquiries too soon. On top of Samkhya’s twenty-four principles, the Tantrikas added another twelve that served to bring together the dualistic universe into oneness. As time passes, it is natural that new ways evolve out of the old ways. Let’s look first at the way Classical Yoga viewed the landscape of the mind, and how it taught the yogi to transcend the ordinary world. Then we will look at how Tantra moved on from there.