I HAVE incurred a large number of debts while writing this book. Grants from the Leverhulme Trust and the Economic and Social Research Council (ESRC grant number L320253203) allowed me time from other academic duties to research and write it. The ESRC grant was awarded under the Council's Global Environmental Change ( GEC) programme, and I owe the programme's director, Jim Skea, and its assistant director, Alister Scott, a special note of thanks for their encouragement and support. During 1996 a distinguished group of academics met three times at Keele University for a series of ESRC-funded seminars to discuss the issues on which I focus in this book, and I benefited more than I can say from those encounters. In particular, Brian Barry, Wilfred Beckerman, Ted Benton, Paula Casal, Alan Holland, Bryan Norton, Jonathon Porritt, and Marcel Wissenburg all helped to deepen my confusion and thereby pave the way to a degree of enlightenment. Chapter 2, which emerged from those conversations, is a version of "Environmental Sustainabilities: An Analysis and a Typology", Environmental Politics, 5/3 ( 1996), and permission from Frank Cass and Co. to use this material is gratefully acknowledged.
Most of the rest of the book was written during a nine-month stay in Spain. I spent much of that time in the convivial surroundings of the Instituto de Filosofía in Madrid, and I owe a debt of gratitude to the Institute's ex-director, Javier Muguerza, and its present one, Manuel Reyes Mate, for enabling me to use the Institute's facilities. All the Institute's staff were unfailingly helpful during my stay there, and the transient population of the 'sala de becarios' provided just the right amount of daily distraction. I was also taken under the wing of the Centro de Teoría Política at the Universidad Autónoma, Madrid, and I am grateful to Fernando Vallespín, Rafael del Aguila, and Angel Rivero for their intellectual stimulation and 'El Tiro' hospitality. Finally, throughout my stay in Spain, Jorge Riechmann, of the Fundación Primero de Mayo, gave me much more of his time