He earned 1998 a PhD (summa cum laude) at the Humboldt University of Berlin with a dissertation titled "Verwilderte Selbsterhaltung.
Zivilisationstheoretische Kulturkritik bei Nietzsche, Freud, Weber und Adorno".
Fischer was from 1998 to 2002 Postdoctoral Research Fellow and coordinator of the interdisciplinary research group Common Good and Civic Spirit at the Berlin-Brandenburg Academy of Sciences and Humanities.
[2] In this research group he worked with some of the most brilliant minds of contemporary political theory in Germany, e.g. Ernst-Wolfgang Böckenförde, Claus Offe, Iring Fetscher, Christian Meier, Otfried Höffe and Klaus von Beyme.
[3] In 2006 he received the venia legendi with a habilitation thesis under the supervision of Herfried Münkler.