The author mainly describes his travel experiences out of astral bodies or travel, it performs from an early age. It is a French author, which is rare in this area. It's a good book, experiments are well described. 1 The experiences described are really good and very similar to experiences I myself live for decades. We feel the sincerity and authenticity. 2 Interpretations of the author on some points, I find it a bit pessimistic about the slow pace of our evolution. He does not mention the continents of Hyperborea, Mu and Atlantis high technology. 3 His feelings when he followed some courses in these areas, I agree with him, some leaders take the big head and may sink into gouroutite!
In short, a good book for the awakening of our consciousness and also to reassure those who share similar experiences without daring to speak, no, they are not crazy, just awakened. As against this is not a book of learning outputs techniques outside the body, for that read the works of Bernard and William Bulhman Raquin.