During Weil's medical studies his interest in philosophy was already evident: his university registration from 1922 includes one of Ernst Cassirer's courses on Philosophy of Language. The following year Weil would move to Berlin while still continuing his studies in Medicine. Over the next decade, Weil, now studying philosophy full-time, would move back and forth between Hamburg and Berlin numerous times. Between Hamburg and Berlin, Weil started his doctoral studies and eventually wrote his dissertation "Des Pietro Pomponazzi Lehre von dem Menschen und der Welt" under Cassirer. It is during this period that he started to publish reviews and articles, as well as work as a private tutor. It was also during this period that he started an association with the circle around Aby Warburg and the  Warburg Library. Moving again back to Berlin from Hamburg in 1930, Weil became the personal secretary to the philosopher Max Dessoir, and became involved in the publication of his journal Zeitschrift für Ästhetik und allgemeine Kunstwissenschaft. In 1932 Weil published his doctoral dissertation. During this tumultuous period Weil read Mein Kampf and understanding the political implications on him as a Jew, he started looking towards his options abroad. He notably applied for a position at the University of Puerto Rico, which he did not receive.