This has been one of my Links since the birth of my blog. Modern thinker and philosopher Ken Wilber is a lifelong meditator with amazing control over his consciousness. I have admired his work and his important teachings for a dozen years, finding him quite helpful in understanding what states of consciousness shamans access. His book, A Brief History of Everything, is a useful introduction to his work. But first, just click on Ken’s pic and he’ll stop his brain waves for you.