- Two-Year Fellow, All Souls College (from 2017 to 2019)
- Visiting Fellow, All Souls College (from 2013 to 2014)
- Executive Editor of The Economist (from 1997 to 2006)
- Editorial staff member, The Economist (from 1984 to 1997)
- Research student at University College London (from 1982 to 1984)
- Undergraduate at Gonville & Caius College, Cambridge (from 1975 to 1978)
- History of philosophy
- History of ideas
- Forthcoming: Ludwig Wittgenstein, Yale University Press, (Jewish Lives series)
- 2016: revised and expanded edition of The Dream of Reason, Penguin / Norton-Liveright
- 2016: The Dream of Enlightenment: The Rise of Modern Philosophy, Penguin (UK) / Norton-Liveright (USA)
- 2000: The Dream of Reason: A history of philosophy from the Greeks to the Renaissance, Penguin (UK) / W W Norton (USA)
- 1997: Socrates, Orion (UK) / Routledge (USA)