Franz Brentano’s Mereology and the Principles of Descriptive Psychology

I analyse Brentano’s argumentative strategy from his lectures in the Deskriptive Psychologie and how he introduces and reframes his fundamental psychological theses. His approach provides us with the reasons why psychology can be distinguished into different domains of investigation and how the tasks of one of these domains—the de-scriptive-psychological one—imply a specific understanding about the structure of consciousness. Thereby a mereology of consciousness is developed, which offers the theoretical background to the aforementioned reframing of the Brentanian theses.