I work within the fields of metaethics, philosophy of action, and philosophy of language. My most recent work has focused upon moral semantics (particularly the logic of practical 'ought' sentences), moral responsibility, and the analogy between moral and mathematical knowledge.

At Princeton, I am affiliated with the Department of Philosophy, the Interdepartmental Program in Political Philosophy, and the University Center for Human Values. I am further affiliated with the School of Social Sciences at the Institute for Advanced Study in Princeton.

For copies of papers and further information on my research, please email me at msiegel at princeton dot edu.