Transcription of a lecture by Eugenio Barba in Warsaw in May 1980 published in Théâtre International no 1, London 1981. It is the first time Barba mentions the new term of theatre anthropology defining it as the study of the human being in a situation of enactment and representation in an organised theatre or dance performance. He points out three technical principles which he considers as the “laws” determining the various acting styles in different traditions.