By analyzing the life-histories of teachers, this paper attempts to describe the ways they lived their experiences from childhood to adulthood and how this process has affected their attitudes towards diversity. It also seeks to examine how these life-histories are conveyed and enacted in the classroom, and hence the possible ways teachers can integrate their cultural knowledge into the teaching-learning process. Socialization and learning experiences throughout life cause metamorphoses in their personal identities. Among the different forms of cultural metamorphoses occurring in teachers, this paper focuses on what I describe as cultural transfusion. By means of this process, I analyze two tendencies in personal identity: the 'intercultural transfuga' and the 'oblato', two concepts to be explained in my text. The former tendency among teachers integrates the culture of origin into the emerging cultural identity, both implicitly and explicitly. The latter denies the culture of origin and idealizes the target culture as its aim in life. Thus, this tendency leads to a 'monocultural' teacher, as I shall argue.