Résumé
This article questions the notion of social capital. Social capital shows that the relationships of an individual to others are potentially beneficial. This involves family, membership of groups, networks or the confidence this individual has in other people and institutions. By integrating social capital, the economics of rational choice incorporates the social conditions under which individuals develop. As the question of the quality of social life becomes crucial, the generalization of the approach of the maximizing agent which finally discovers the social structures is not very convincing. On the contrary, social capital may be considered as an explanation of the consequences of economic transformations due to the combination of the decrease of welfare expenditures and the improvement of the level of education.