Abstract
The paper concetraces on Cassirer's understanding of Kepler's role in the fight for the "Denkraum"; it analyzes Cassirers "idealization" of Kepler's revolutionary redefiniton of space and the subsequent use of this idealized figure in the philosophical treatment of science as one of the key formative forces responsible for (re)creating the reflective as well as political space, the space of humanistically understood freedom. Key words: