The article pursues the two related questions of how economists pretend to know and why they want to know at all. It is argued that both the economic form of knowledge and the motivation of knowing have undergone a fundamental change during the course of the 20th century. The knowledge of important contemporary economic textbooks has little in common with an objective, decidedly scientifically motivated knowledge. Rather, their contents and forms follow a productive end, aiming at the subjectivity of their readers.