One has to establish a chronology of Marx's works on economics in order to understand the importance of this unpublished chapter of Capital; all the more so because Marx was unable to complete this work. It is vital to discover the common framework, the central preoccupation around which all the works are orientated. Marx himself indicated the line of their development. Two main questions emerge from all these works (be they completed, or as plans and sketches): 1. the origin of value, its characteristics and forms; 2. the origin of the free worker, the wage-labourer. We shall deal with them in this order and analyse the consequences they imply.