This article presents three tensions related to the concept of 'difference' in the social and historical sciences. The first tension is related to ethnocentrism and anachronism: the author shows that they both represent simultaneously dangers that must be prevented and unavoidable working tools. The second tension is related to the role of conceptualization and to the difficult choice that social scientists have to make between 'native categories' and 'analytical categories'. Finally, the third dilemma is related to the impossibility for the researcher to find a right distance (juste distance) in relation with the world he studies (be it a familiar or unfamiliar world). The author attempts to show that, although these tensions are often thought of separately, they are in fact closely related, and concern the need for all research projects to be taking the social world as their research object.
