Gestalt is a concept introduced to solve the problems of unity, connection and order that objects manifest in experience. Philosophers trained at Franz Brentano’s teaching began to work on it to address epistemological and ontological questions about perception, cognition and the structure of objects. This work was seminal for Gestalt psychology, from the research of the Graz and Berlin Schools, carried on by Cesare Musatti, Fabio Metelli, Gaetano Kanizsa, Paolo Bozzi in Padua and Trieste, Albert Michotte and Paul Fraisse in Louvain, to that of Edgar Rubin and David Katz, but also of Karl Bühler, Egon Brunswik and Ludwig Kardos in Wien