Abstract

Within liberal theory, the concept of rationality plays a double role, descriptive and normative. This article focuses on the conceptual relationships which take place between these two aspects of rationality, with a particular concern for the use of this concept among three major liberal thinkers, Adam Smith, Friedrich von Hayek, Raymond Boudon. The thesis aims at identifying not only features common to the concept of rationality - which could be attributed to a liberal way of formulating this concept - but also a trend towards a concept of individual rationality that is more flexible and more complex and that is able to take into account the multi-dimensional aspect of the logic of social action: an adaptive dimension, a congnitive and a moral one.