Few authors have shaped the 20th century as much as Sigmund Freud, who established not only a new theoretical framework and psychotherapeutic method with psychoanalysis but also a global organization. Freud's writings have generated an overwhelming amount of secondary literature and have been the subject of numerous ongoing controversies. This introduction by Andreas Mayer seeks a fresh approach by illuminating their scientific and cultural historical contexts and highlighting their collective character. In contrast to a view that considers Freud's central concepts as stable conceptual units, a dynamic perspective is developed that reveals the traces of the historical process within the texts themselves.