After a period as Humboldt-Fellow at the University of Frankfurt, working with Axel Honneth, and as Associate and later full Professor of Philosophy at the University of Oslo, Hammer spent seven years (1998-2005) as Lecturer and later Reader in the Department of Philosophy at the University of Essex. From 2006 to 2008 he was a Recurrent Visiting Professor at the Center for the Study of Cultural Complexity, University of Oslo. Between 2005 and 2009 he served as Visiting Professor of Philosophy at Temple University, The New School, and University of Pennsylvania before, in 2009, becoming Professor of Philosophy at Temple University. Since 2021 he has chaired the Philosophy Department at Temple.
In 1995, Hammer published a Norwegian translation of Immanuel Kant’s Kritik der Urteilskraft.[2]
His first book, Stanley Cavell: Skepticism, Subjectivity, and the Ordinary (Polity Press, 2002) analyzes the philosophy of Stanley Cavell in the context of Wittgenstein, ordinary language philosophy, and the question of selfhood.
In Adorno and the Political (Routledge, 2005), Hammer reconstructs the often neglected political dimension of Theodor W. Adorno’s thought. As opposed to a widespread view of this philosopher as an apolitical aesthete, Hammer shows how important the political is for his work, and how political questions influence both his theoretical contributions and his social involvement.[3][4][5]
A more recent monograph, Philosophy and Temporality from Kant to Critical Theory (Cambridge University Press, 2011), reinterprets central figures from the European philosophical tradition, including Kant, Hegel, Schopenhauer, Nietzsche, and Adorno in terms of their views of temporality.[6][7] It is claimed that with the onset of modernity, lived time engenders a sense of crisis focused on existential meaning and transitoriness.[8] While recognizing this crisis, these thinkers each present recommendations for how this crisis should be tackled.[9] The study demonstrates Hammer’s interest in re-reading the canon from the vantage-point of the question of modernity and modernization.[10] For the publication, Hammer was granted the 2012 Canadian Society for Continental Philosophy Symposium Book Award.[11]
Hammer’s subsequent book, Adorno’s Modernism: Art, Experience, and Catastrophe (Cambridge University Press, 2015) is a comprehensive study of Theodor W. Adorno’s aesthetics and its relation to metaphysics, politics, and culture.[12][13]
After the Death of God: Secularization as a Philosophical Challenge from Kant to Nietzsche, a study of secularization and philosophy of religion in the post-Kantian tradition, is published by the University of Chicago Press (2025). His Routledge Guidebook to Horkheimer and Adorno’s Dialectic of Enlightenment, co-authored with Fred Rush, came out in 2025.
Hammer is the editor of German Idealism: Contemporary Perspectives (Routledge, 2005), Theodor W. Adorno II: Critical Assessments of Leading Philosophers (Routledge, 2015), and Kafka’s The Trial: Philosophical Perspectives (Oxford University Press, 2018).[14] With Peter Gordon and Axel Honneth, he edited The Routledge Companion to the Frankfurt School (2018). With Peter Gordon and Max Pensky he edited A Companion to Adorno (Wiley-Blackwell, 2020). He has also co-edited two German books: Stanley Cavell: Die Unheimlichkeit des Gewöhnlichen (Fischer Verlag, 2002) and Pragmatik und Hermeneutik: Studien zur Kulturpolitik Richard Rortys (Felix Meiner Verlag, 2011).
Hammer has published four Norwegian monographs: Adorno (Gyldendal, 2002), Det indre mørke. Et essay om melankoli (Universitetsforlaget, 2004, translated into Swedish, Russian, and Serbian), Anstendighet og revolt: Noen betraktninger omkring Dag Solstads forfatterskap (Oktober, 2011), and USA. En supermakt i krise (Kagge, 2021). In USA. En supermakt i krise, he analyzes the causes of American political polarization.[15]
He is a frequent contributor to public debate and has several times written for New York Times’ The Stone. From 1990 to 1996 he co-edited the Norwegian journal of philosophy Agora.
