The awakening of the Teilhardian genius took place on the battlefields of the Great War. The "baptism in the real," as he himself called it, led Pierre Teilhard de Chardin to write these texts that constitute an essential key to understanding the subsequent evolution of his religious, philosophical and scientific thought. In the middle of the front butchery, where he serves as a stretcher and chaplain, the mystical soul of Teilhard opens up to high considerations about the deep meaning of life, death, history or the cosmic Christ that becomes transparent in bloody matter . Teilhard writes mostly for himself. Write a testimony, almost a will. He does not communicate his writings more than a small number of people. He does not expect to be able to publish them. Everything I had seen, felt, thought, during that extraordinary period from which he emerged transformed, could one day reveal it? He himself was anxiously asking himself this question on the eve of his demobilization: "Will I ever be understood?" He was at the starting point of his great intellectual adventure. This new edition of the Writings of the Time of War is offered in two volumes. The first, The Cosmic Life, includes the first seven essays between 1916 and 1917. The second, La gran Mónada, presents the thirteen remaining essays, belonging to the years 1918 and 1919.