CONTENIDO: Methods of presentation. -- The Naven ceremonies. -- The concepts of structure and function. -- Cultural premises relevant to the Wau-Laua relationship. -- Sorcery and vengeance. -- Structural analysis of the Wau-Laua relationship. -- The sociology of Naven. -- Problems and methods of approach. -- The ethos of Iatmul culture: the men. -- The ethos of Iatmul culture: the women. -- Attitudes towards death. -- The preferred types. -- Ethological contrast, competition and schismogenesis. -- The expression of ethos in Naven. -- The Eidos of Iatmul culture.