This research project starts out from the hypothesis that decisions made by intentionally rational actors under conditions of uncertainty are based on "fictions." Fictions are images of a future state of the world and the causal mechanisms that lead to this state. Actors are motivated by this imagined future and organize their current actions accordingly. Since these mental images are not tethered to reality, fictionality is also a source of creativity. The concept of fictionality can lead to a better understanding of the microfoundations of economic dynamics. The aim of this project is to publish a monograph on the role of fictionality in economic action. The book will draw on several years of research about the action-theoretical foundations of economic sociology, innovation processes, the creation of symbolic value, and the operation of money in the economy. Project duration: January 2012 to August 2013.