The Meaning of Exile of Erich Fromm from Frankfurter School
First, it means the nature of the critical theory changed from interdisciplinary materialism to a kind of philosophy. Horkheimer declared the purpose of the critical theory in ‘Traditional and Critical Theory’(1937). According to him, critical theory aims interdisciplinary materialism that organized some discipline for practice. But regardless of the statement, actual interdisciplinary project was not so many. At least, actually successful project was only ‘Authority and family’(1936). This project was based on large-scale Weimar workers survey and the project was mainly designed by Fromm. In earlier Frankfurt school, Fromm played a central role. But Adrno replaced Fromm. With participation of Adrno, the critical theory changed it's nature more to the philosophy. It originally aimed at theory and praxis but after Adrno's replacement, it gave up the praxis.
Second, it means change of basic understanding of Freud's libido theory.
Psychoanalysis was brought to the school by Fromm and used as effective tool. But later he was ejected because of conflict with members.
Fromm presuposed socialized person and at first Horkheimer followed Fromm's understanding. But Adrno opposed to that and Horkheimer changed his attitude to Fromm.