Have you had a moment that reshaped your life? Was there and experience that brought about an almost instantaneous shift in the course of your thinking and the way you you've lived? Today we'll consider the power of a paradigm shift with two people who've been very public about their life altering moments. First, Dr. Eben Alexander, a renowned academic neurosurgeon, spent 54 years honing his scientific worldview until a transcendental near-death experience. Later, we talk with ABC News' Dan Harris about how an on-air breakdown in front of five million people left him forever changed.