Wilfred R. Bion (1961) uses the term basic assumption to designate that which, fundamentally, the individual must assume in order to be part of a group. Basic assumptions come into play at the unconscious, pathic, and affective levels.
Competing with the model of the work (W ) group, which is focused on a task and puts into effect the secondary processes of rational thought and "reality-testing," group activity is based on three basic assumptions that are discernible in the affective tone of the relations of group members among themselves and with their leader. The basic assumption of dependency (baD ) lends cohesion to the group by means of supporting the assumption that nourishment, protection, knowledge, and life can come only from the wisdom of a leader who is omnipotent and omniscient, akin to a magician. The basic assumption of fight/flight (baF ) brings individuals together around the violent, excitation-saturated feeling that the salvation of the group and its individual members depends on the fact that their leader will enable them to identify, and then successfully fight or flee, a specific enemy either within or outside the group. The basic assumption of pairing (baP ) enables the group to come together as such through the members' sharing of an implicit, mysterious hope, sparked by the assumption that a couple will give birth to a messiah, a new guide, a new idea, or a new theory or ideology.
These basic assumptions are states of mind—all of them sexual in the final analysis—associated with the characters in the oedipal situation (including the Sphinx); they emerge as secondary formations from an extremely primitive scene that is played out at the level of part-objects, and which is associated with psychotic anxieties and with the mechanisms of splitting and projective identification inherent in the schizoid-paranoid and depressive positions posited by Melanie Klein.
See also: Bion, Wilfred Ruprecht; Group analysis.
Bion, Wilfred R. (1961). Experiences in groups. London: Tavistock Publications.
Freud, Sigmund. (1921c). Group psychology and the analysis of the ego. SE, 18: 65-143.
Grinberg, León, Sor, Dario, and Tabak de Bianchedi, Elizabeth. (1977). Introduction to the work of Bion: groups, knowledge, psychosis, thought, transformations, psychoanalytic practice (Alberto Hahn, Trans.). New York: J. Aronson. (Original work published 1973)
Klein, Melanie. (1946). Notes on some schizoid mechanisms. International Journal of Psycho-Analysis, 27, 99-110.
Pines, Malcolm (Ed.). (1985). Bion and group psychotherapy. London: Routledge.