What sets humans apart from animals? Undoubtedly, it is the intellect's ability to reflect on life, death, and beyond. Only we can ask: "What power gives life to my body?" The Kena Upanishad is a sacred text that deeply explores this existential question. With his unusual background combining a rigorous education in science and a committed practice of yoga wisdom, Vivek Desai brings to light the relevance and practical application of this ancient scripture, making it accessible to the modern reader without compromising its sublimity.The focus of this translation and reflective commentary is on guiding readers to find fulfillment in their lives. In Who Thinks? Who Breathes? Reflections on the Kena Upanishad… • An accessible English translation • Lucid reflections, relevant to modern life • Pragmatic interpretations of sublime revelations • Simple diagrams to help understand esoteric concepts • Short but powerful meditations to give a firsthand experience of our true nature