The formula « voluntary servitude » is mobilized without being necessarily referred to La Boétie's Discourse. The paradoxical and enigmatic aspect of the expression seduces. This book provides a critical analysis of it and proposes avatars that are more suitable to explain the phenomenon it indicates.

Of the writing of the great engineer and mathematician Simon Stevin (Bruges 1548 - The Hague? 1620), it is predominantly his scientific work, striking for its diversity and intention to serve as practical handbooks, which has survived the passage of time. His numerous works, almost all in Dutch, cover areas as diverse as arithmetic and navigation.