Abstract
Analysing Cassirer's positions in the Nachruf dedicated to Natorp (1925) and in the third volume of the Philosophy of Symbolic Forms (1929), I will try in this short paper to outline the core, merits, and limitations of Natorp's psychology in Cassirer's interpretation. In doing so, I will emphasise three elements: 1. the cornerstones of Natorpian psychology, which for Cassirer represent Natorp's main contribution to the history of ideas; 2. the thematic unity of Natorp's philosophical production; 3. the fundamental continuity between Natorp's research and that of Cassirer. These three aspects are interwoven and belong in some way to the inner development of Marburg Neo-Kantianism.