The essay was published in Italian in Tecniche della rappresentazione e storiografia (1992), which collected material from the 6th session of ISTA held in Bologna in 1990. This text by Cruciani in the year of his death (1992) can be considered a summa of his continuous questioning on the not ephemeral nature of theatre and on the system of symmetries that he established existed between theatre practices and historiographic research. The author reflects how theatre is a field of investigation and argues why, from his point of view, theatre studies should be in a dialectical relationship with social, pedagogical, artistic, anthropological and historical studies. He identifies one of the values of theatre in its being a long-lasting category owing "its continuity and persistence in history because it does not produce works, but rather ways of operating".