I am a historian of ancient philosophical and scientific ideas and the way they shaped and continue to shape our Western intellectual tradition. One focus of my research is the history of Platonism, but I have also strong interests in Pre-Platonic philosophy as well as moral philosophy and Greek literature. Educated at the Universities of Marburg and Cambridge (Ph.D. in Classics in 1984), I first held a Junior Research Fellowship at Caius College, Cambridge, taught briefly at UT Austin and then, for six years, at the Freie Universität Berlin. I am emeritus professor of Classics at Princeton University, where I taught from 1996 to 2017, serving also as Master of Forbes College from 2006 to 2010 and academic director of the Program in Hellenic Studies from 2010 to 2017.
My main publications deal with the reconstruction and interpretation of a sixth century anti-Aristotelian treatise on the eternity of the world, written by the Alexandrian philosopher John Philoponus, and the meaning and function of deities in Euripidean tragedies. More recently, I have edited volumes on such diverse topics as mysticism, Aristotle's cosmology, and the cult of Dionysus. My current research interests concern the so-called “Presocratics” and the beginnings of Western philosophical thought as well as the development and influence of ancient conceptions of evil. I also try to further our understanding of Egyptian philosophical thought (as preserved in the enigmatic Corpus Hermeticum) and its profound influence in late antiquity.
In addition to my research and teaching, I am serving as co-editor of two monograph series, Philosophia Antiqua (Brill) and Studien und Texte zu Antike und Christentum (STAC, Mohr-Siebeck). I am also co-editing APEIRON, an international journal for the history of science and philosophy.
Philoponus against Aristotle on the Eternity of the World. London: Duckworth 1987, 182pp.
John Philoponus’ Criticism of Aristotle’s Theory of Aether. Peripatoi Vol. 16, Berlin, New York: DeGruyter 1988, 274pp.
Simplicius against Philoponus on the Eternity of the World. London: Duckworth 1991, pp. 95-135. (Co-authored with David Furley).
Hyperesie und Epiphanie. Ein Versuch über die Bedeutung der Götter in den Dramen des Euripides. Zetemata 109, Beck Verlag, München 2002, 231pp.
Edited Volumes (published and in progress)
Euripides and Tragic Theatre in the Late Fifth Century. Co-edited with Martin Cropp, Kevin Lee, David Sansone, Eric Csapo and Donald Mastronarde. Illinois Classical Studies 24/25, Champaign, Il., 2000.
Religion, Mysticism, and Ethics: A Cross-traditional Anthology. Co-edited with Daniel Zelinski. Archiv für Religionsgeschichte 9. Saur Verlag Munich, 2007.
New Perspectives on Aristotle’s De caelo. A collection of interpretative articles on Aristotle’s cosmological treatise. Co-edited with Alan Bowen. Philosophia Antiqua 117, Brill, Leiden 2009, 321pp.
Dionysos und die vordionysischen Kulte. A posthumous edition of Vyacheslav Ivanov’s manuscript on Dionysiac Religion. Co-editor with Michael Wachtel. (Submitted to Mohr - Siebeck).
A Handbook of Neoplatonism. Oxford University Press (in preparation).
Selected Articles and Reviews
“Philosophy in the Age of Justinian”. In: The Age of Justinian, ed. by Michael Maas, Cambridge University Press, 2005, pp. 316-40.
“Proclus: A Life”, in All From One: A Guide to Proclus, ed. by Piet d’Hoine and M. Martijn, Oxford University Press. 2017, pp. 1–26.
“Neoplatonism”: Stanford Encyclopedia of Philosophy (Internet publication): http:// plato.stanford.edu
“Three Neoplatonic Introductions to Philosophy: Ammonius, David, and Elias.” Hermathena cxlix (1990), pp. 33–51.
“Impetus Theory and the Hermeneutic of Science in Simplicius and Philoponus,” Hyperboreus 5 (1999), pp. 107-124.
“Aristotle on Qualitative Influence: On Generation and Corruption I 7” In: Aristotle’s On Generation and Corruption I, Proceedings of the Symposium Aristotelicum 1999, Frans de Haas and Jaap Mansfeld (eds.), Oxford University Press, 2004, pp. 219-242.
“Socrates and Euripides”. In: The Companion to Socrates, ed. by Sara Rappe and Rachana Kamtekar, Oxford, Blackwell 2006, pp. 21–35.
“Piety as Service, Epiphany as Reciprocity: Two Observations on the Religious Meaning of the Gods in Euripides”, Illinois Classical Studies 24-25 (1999-2000), pp. 235-256.
“The Rise and Fall of the Socratic Notion of Piety.” Proceedings of the Boston Area Colloquium in Ancient Philosophy 18 (2003), pp. 1-28.
“Dionysus in the Mirror of Philosophy: Heraclitus, Plato, Plotinus” in R. Schlesier, Dionysos: A Different God?, Berlin 2011, pp. 205–232.
“A World of Thoughts: Plotinus on Nature and Contemplation” (Enn. III 8.  1-6). In R. Chiaradonna and F. Trabattoni, Physics and Philosophy of Nature in Greek Neoplatonism. Proceedings of the European Science Foundation. Leiden, Brill, 2009, pp. 121–143.
“The Will and its Freedom: Epictetus and Simplicius on what is up to us”, in P. Destrée, R. Salles, M. Zingano (eds.), What is up to us? Studies on Agency and Responsibility in Ancient Philosophy. Sankt Augustin: Academia Verlag, 2014, pp. 329–50.
“The Genesis of a Genesis: Corpus Hermeticum III”, in: Lance Jenott and Sarit Kattan Gribetz, eds. Jewish and Christian Cosmogony in Late Antiquity. Texts and Studies in Ancient Judaism. Tübingen: Mohr Siebeck, 2013, pp. 124-149.
Ancient Philosophy and Science, Pre-Platonic philosophy, Plato, Aristotle, Greek Tragedy, Late Antiquity, Neo-Platonism, Hermetism in antiquity