In a live appearance at UCLA’s Royce Hall, New York Times best-selling author and spiritual thought leader Eckhart Tolle explains the awakening of consciousness by taking on one of Oprah's signature questions: What do you know for sure? "I know for sure that I'm sitting on a chair," Eckhart says. "That's the most surface level of things. I know for sure that this is a table." His answer is simple enough, but Eckhart delves further. Even these seemingly simple truths are not concrete, he says. Eckhart goes so far as to say that we can't know for sure that life is not a dream, a question that has been posed by many philosophers. Eckhart explains the importance of becoming more present in our daily lives and why the ability to become still is essential.