Oprah Winfrey, Tom Hanks and David Letterman are just some of the dozens of celebrities who sought out Bob Roth to learn Transcendental Meditation (TM), a mantra-focused meditation practice. Roth, who has been a meditation teacher for over 40 years and has a new book out called, "Strength in Stillness," talks about how he found TM and addresses the criticism and suspicions some former members have raised around TM.