Geoffrey Brennan is an economist who works at the intersection of economics, political science, and moral and political philosophy. He is the author of five books including two with Nobel Laureate James Buchanan. He has served as editor of Economics and Philosophy and Economic Record; and as the President of the international Public Choice Society. His work covers a wide range of topics from 'expressive' voting theory (Democracy and Decision [CUP, 1993] with Loren Lomasky) to The Economy of Esteem (OUP, 2004) with Philip Pettit; and he now describes himself as a scholar in Philosophy, Politics, and Economics. He is currently working on a book on Philosophy and Economics. He holds regular Professorial positions in Philosophy at the Australian National University and in the Political Science Department at Duke University and the Philosophy Department at UNC-Chapel Hill, where he directs the joint Duke/UNC PPE program.Lina Eriksson is a philosopher and political scientist, with a background in mathematics. After her PhD in political science at Gothenburg University, and a year at Harvard as a Fulbright Visiting Scholar, she spent five years at the Australian National University as a post doctoral researcher. She is now Lecturer in Philosophy at Flinders University. Her research covers positive political theory (a book on this, Rational Choice Theory; Potential and Limits, was published in 2011), democratic theory, decision theory, ethics, and welfare-state studies.Robert Goodin is a philosopher and political scientist. He is Distinguished Professor of Social & Political Theory and Philosophy in the School of Philosophy at Australian National University, as well as Professor of Government at the University of Essex. A Corresponding Fellow of the British Academy, Goodin is founding editor of The Journal of Political Philosophy and of the Cambridge University Press series of books on 'Theories of Institutional Design'. He served as general editor of the eleven-volume series of Oxford Handbooks of Political Science. His own work straddles democratic theory (e.g. Reflective Democracy [OUP, 2003]), empirical welfare-state studies (e.g., The Real Worlds of Welfare Capitalism [CUP, 1999]; Discretionary Time [CUP, 2008]), and theoretical reflections on public policy (e.g., Social Welfare as an Individual Responsibility [CUP, 1998]; What's Wrong with Terrorism? [Polity, 2006]).Nicholas Southwood is a research fellow in the School of Philosophy at Australian National University. He works primarily in moral and political philosophy with a particular focus on normativity and practical reason. He is the author of Contractualism and the Foundations of Morality (OUP, 2010) and many articles in journals including Mind, Ethics, Nous, and Philosophical Studies. He has been a co-editor of the Journal of Political Philosophy since July 2012.

Given the wide range of literatures discussed, readers are likely to find much of interest.

• PART I: EXPLAINING THE NATURE OF NORMS; PART II: EXPLAINING THE EMERGENCE, PERSISTENCE AND CHANGE OF NORMS; PART III: EXPLAINING WITH NORMS

Geoffrey Brennan is an economist who works at the intersection of economics, political science, and moral and political philosophy. He is the author of five books including two with Nobel Laureate James Buchanan. He has served as editor of Economics and Philosophy and Economic Record; and as the President of the international Public Choice Society. His work covers a wide range of topics from 'expressive' voting theory (Democracy and Decision [CUP, 1993] with Loren Lomasky) to The Economy of Esteem (OUP, 2004) with Philip Pettit; and he now describes himself as a scholar in Philosophy, Politics, and Economics. He is currently working on a book on Philosophy and Economics. He holds regular Professorial positions in Philosophy at the Australian National University and in the Political Science Department at Duke University and the Philosophy Department at UNC-Chapel Hill, where he directs the joint Duke/UNC PPE program.Lina Eriksson is a philosopher and political scientist, with a background in mathematics. After her PhD in political science at Gothenburg University, and a year at Harvard as a Fulbright Visiting Scholar, she spent five years at the Australian National University as a post doctoral researcher. She is now Lecturer in Philosophy at Flinders University. Her research covers positive political theory (a book on this, Rational Choice Theory; Potential and Limits, was published in 2011), democratic theory, decision theory, ethics, and welfare-state studies.Robert Goodin is a philosopher and political scientist. He is Distinguished Professor of Social & Political Theory and Philosophy in the School of Philosophy at Australian National University, as well as Professor of Government at the University of Essex. A Corresponding Fellow of the British Academy, Goodin is founding editor of The Journal of Political Philosophy and of the Cambridge University Press series of books on 'Theories of Institutional Design'. He served as general editor of the eleven-volume series of Oxford Handbooks of Political Science. His own work straddles democratic theory (e.g. Reflective Democracy [OUP, 2003]), empirical welfare-state studies (e.g., The Real Worlds of Welfare Capitalism [CUP, 1999]; Discretionary Time [CUP, 2008]), and theoretical reflections on public policy (e.g., Social Welfare as an Individual Responsibility [CUP, 1998]; What's Wrong with Terrorism? [Polity, 2006]).Nicholas Southwood is a research fellow in the School of Philosophy at Australian National University. He works primarily in moral and political philosophy with a particular focus on normativity and practical reason. He is the author of Contractualism and the Foundations of Morality (OUP, 2010) and many articles in journals including Mind, Ethics, Nous, and Philosophical Studies. He has been a co-editor of the Journal of Political Philosophy since July 2012.

Given the wide range of literatures discussed, readers are likely to find much of interest.

• PART I: EXPLAINING THE NATURE OF NORMS; PART II: EXPLAINING THE EMERGENCE, PERSISTENCE AND CHANGE OF NORMS; PART III: EXPLAINING WITH NORMS