Self-interest has two paradoxical features. On the one hand, classical economic thinking has proposed that markets are created by self-interested individuals who enter into economic exchanges following their private interests. Bernard Mandeville and Adam Smith have argued that, perhaps against our first intuitions, actions based exclusively upon selfish motivations, articulated with the division of labour and with market relationships, lead to an increase of the common good. These early contributions to classical economics have been immensely influential in economics and political thinking, and the loose set of ideas grouped under the banner of ‘neo-liberalism’ owes no small debt to the classical liberal image of private vices turning into public benefit under the guidance of the invisible hand of the market. But self-interest has another property which threatens to annul its brighter side. If self-interest is unbridled, if nothing else but self-interest reigns supreme, can we even hope for markets to do their hidden work? Can selfinterest exclusively by itself guarantee that people will become market actors, that individuals can successfully follow their private good in the anonymous, atomised market of textbook economics?