In his book, Hans-Jörg Rheinberger explores new approaches to the history of modern sciences. At its core is a description of the material arrangements that laboratory scientists in the 20th century refer to as their experimental systems. For some time now, theorists and historians of natural sciences have been paying greater attention to the experiment. Rheinberger attempts to develop an epistemology of modern experimentation based on the concept of experimental systems. The dynamics of research prove to be a process of forming epistemic things: empirical sciences evolve in their engagement with their subjects. Thus, it is about a shift in perspective away from the ideas and intentions of the actors and towards the objects that their actions and desires are directed at.