Approachable yet sophisticated, this book takes the reader on a gently guided tour of one of the most important texts Tibetan Buddhism has to offer. Certainty in this context refers to the unshakeable trust that develops as meditators discover for themselves the true root of reality. In this authoritative presentation, master teacher Anyen Rinpoche opens wide the storehouse of this richly philosophical text in a way that lets readers of all backgrounds easily benefit.