Elsewhere Bergson criticized the philosophy of cut hairs, but in this essential text of his work, one can not say that it always escapes this pitfall, but perhaps is this vision of a reader unused to the philosophy and who criticized him in general to try to confuse us in impeccable argument even as we enter areas where nothing can be proved. That said, there are very many passages in the book where the beauty of expression flows so naturally in the intuitions and the thought of the author, then it is a pure delight to read. The philosophy becomes then poetry, and some small sentences soon begin to haunt you. The GF edition offers high marks to illuminate the text. The introduction on it is uneven and not always understandable if you have not first read the text.