This book in the series of Life and Vision of Vedic Seers is an attempt at reconstruction of the life-history of one of the most primeval seers of the Vedic age, who is known best to the academic circle but has remained an important source of inspiration to the Indian psyche throughout its history in determining its moral courage for its sense of detachment, self-sacrifice in the cause of others and peace. This is the introduction to Dadhyan Atharvana, popularly better known as Dadhici, the same seer who is famous for having donated his back-bone to Indra for killing Vrtra, the embodiment of evils in the world, while living and meditating on the back of the river Sarasvati. He has been referred to in this capacity as many as eleven times in the Rgveda alone and has contributed five last chapters to the Yajurveda including the famous Santipatha which has received the acclaim of the United Nations also and is chanted in India as well as in countries wherever there is prevalence of the Vedic culture throughout the world on each sacred occasion. He is the seer also of the Isa Upanisad whose very first mantra has been acclaimed by Mahatma Gandhi amounting to our entire sacred literature including the Vedas, Upanisads, Bhagavadgita out along with this background for the first time, this book is expected to serve as the best commentary on the Isa Upanisad written by anyone so far. The book is valuable asset for scholars, students, researchers of Philosophy, Yoga, Vedic studies and ideology.