Research on human behaviour, when observing an individual, observes also the observer. This research setting is the source of the observer’s main intellectual anxiety, and constitutes, according to Georges Devereux, the specificity of human sciences and the problematic core of this field of study. Due to this perspective, Devereux’s theoretical contribution goes beyond the boundaries of ethnopsychiatry. In the dialogue between quantum epistemology and Freudian epistemology, Devereux proposes a new approach, i.e. to change the focus of research from the observed to the observer. The Freudian concept of countertransference subsequently becomes the methodological criteria by which the observer’s anxiety acquires a scientific status. The observer’s anxiety, in the traditional approach, constitutes an obstacle
Keywords: Devereux, etnopsichiatria, rifondazione epistemologica delle scienze dell’uomo, principio di complementarità, controtransfert.