When the University La Sapienza, in Rome, did me the honour of asking me to deliver the Federico Caffè lectures of 2003, I thought this could provide a welcome opportunity to gather my work of more than three decades on a human conduct which turns out to be pervasive, basic and often crucial in social and economic life, the solution of many of its problems and the cause of some of them: reciprocity. Whether they are conspicuous or taken for granted, various conducts of reciprocity are necessary for the existence of a peaceful society in which people and their rights are respected; they are the main correctors of market and organization failures and sometimes their cause; they constitute the very substance of the life and economy of families and various communities; they are essential in various aspects of the working of the public and political sector; and they inspire both most of the policies of “welfare regimes” and farther visions of human betterment. Reciprocity is the conduct that can provide fairness in freedom, sustainable altruism and mutual appreciation of all types and intensities.

My analyses of reciprocity and its causes and consequences have appeared over more than three decades in various languages, including the 1984 book in French La Réciprocité Générale – La Bonne Economie (and are now generally out of print).