Thomas theorem: situations we define as real, become real in their. Successful interaction: need shared understanding of situation. Definition of the situation: in certain contexts. people define situations differently often in contradictory ways, based on their own subjective experiences. Erving goffman: presentation of self in everyday life (1959) Dramaturgical approach: methodology of everyday life taking place on a stage. Front stage for public display - mr. bean: appearance-social status, manner- conduct. Back stage for personal encounters - rowan atkinson: love for fast expensive cars. Impression management: describes tactics people employ when presenting themselves publicly. Social interaction: statuses we hold, and roles we perform. Integral part of our interactions with others and their interaction with us. Total institution serves to resocialize by regulating all aspects of a person"s life. Prison, psychiatric institutions, residential and reform schools, military. 1971: planned two-week investigation into the social psychology of prison life. Guards became sadistic and prisoners became depressed and with signs of extreme stress.