Texte founder of Chinese civilization and masterpiece of its philosophy, Yi Jing has today become a heritage of humanity. The Book (Jing) of Changes (Yi) has long been taken for a book of divination, but in reality it does not reveal anything which should be the object of irrational belief. Its 64 hexagrams are in no way supposed to “predict the future”. But, their structure and the comments which accompany them, imbued with Taoist and Confucian wisdom, can help everyone to find the harmonious adequacy between the project which it carries out and the whole in which it is inscribed. Thus, Yi Jing becomes a modern tool of investigation, both for daily action and for self-knowledge.