The paper focuses on the concept of matter and the material in Edgar Zilsel’s considerations about historiographical methods in the context of the Marxist debates on the materialist conception of history in the 1920s and 1930s (György Lukács, Max Adler). It sheds light on Zilsel’s understanding of matter as fluctuating, interfering processes in the lapse of time and the related concept of irreversible laws and relates it to Ernst Mach’s philosophy and to Richard Semon’s theory of mneme . Finally, it (...) shows the practical consequences of the concept of materialism in Edgar Zilsel’s epistemology. (shrink)