Based on the criteria required for reading a book, two general notions, the “text” and the “manuscript”, are defined and explained at the beginning of this article from a semiological point of view. On this basis, several editions of Ferdinand de Saussure's manuscripts are then analysed, highlighting the deficiencies, which are often due to the disorder created in archive collections by superimposing manuscripts. A better classification of a primordial manuscript and the dating of another published manuscript are thus brought to light. Finally, it is proposed that this distinction between “text” and “manuscript” must be adopted and that Saussure's texts be favored in the reading and study of Saussure's manuscripts.