He was educated at Christ's Hospital, Balliol College, Oxford, and University College, London. Elected a fellow of New College in 1969, he returned in 1996 to take up the Wardenship. He was made a Fellow of the British Academy in 1986.
Ryan is a recognised authority on the work of John Stuart Mill, having contributed directly to the ‘Reversionary’ school, which led to a re-examination of Mill’s work from the 1970s. His academic work also takes in broader themes in political theory, including the philosophy of social science, the nature of property, and liberalism of the 19th and 20th centuries.
Ryan has held positions at the Universities of Oxford, Essex, Keele, Princeton University, as well as the University of Virginia School of Law. He was also a Visiting Professor of Political Science at The University of Texas at Austin, Australian National University, The New School and many others.
Ryan is a regular contributor to the New York Review of Books, the London Review of Books, and the Times Literary Supplement. Ryan can be heard here giving a brief account of Mill's philosophy, and a defence of him as the greatest British philosopher, on the BBC Radio 4 programme In Our Time.
- The Philosophy of John Stuart Mill (1970): an examination of Mill's philosophy of science, its relation to his ethical thought, and a defence of the view that Mill's work is largely coherent, concentrating on Mill's A System of Logic.
- The Philosophy of the Social Sciences (1970): an introduction to the philosophy of social science.
- J.S. Mill (1975): a guide through the important works of Mill, and the themes to be found therein.
- Property and Political Theory (1984)
- Property (1987)
- Russell: A Political Life (1993)
- John Dewey and the High Tide of American Liberalism (1995)
- Liberal Anxieties and Liberal Education (1998): given as a lecture series at the University of California, Berkeley, contains autobiographical material.
- On Politics: A History of Political Thought: From Herodotus to the Present (2012) traces the origins of political philosophy from the ancient Greeks to Machiavelli in Book I and from Hobbes to the present age in Book II
- The Making of Modern Liberalism (2012) exploration of the origins and nature of liberalism from the Enlightenment through its triumphs and setbacks in the twentieth century
- "Birthday's today". The Telegraph. 9 May 2013. Retrieved 29 April 2014. "Prof Alan Ryan, Warden of New College, Oxford, 1996–2009, 73"
- Prospect magazine
- New York Review of Books
- Alan Ryan: CV
- Department of Politics and International Relations
- Debrett's People of Today (12th edn, London: Debrett, 1999), p. 1715
- Booknotes interview with Ryan on the Introduction to Alexis de Tocqueville's Democracy in America, February 26, 1995.