In our previous work we have sketched four social psychological relationships involved in both scientific gatekeeping and the formation of methodological, theoretical and metatheoretical consensuses within a research paradigm. We recently discussed a fifth gatekeeping relationship involving the filtering of scientific information between primary journals and textbook accounts, and the consequent use of the undergraduate teaching relationship to stream disciplinary apprentices. The present study examines how textbooks have helped to define the conceptualization of social psychology as an intellectual, research domain, and have helped to demarcate it as a legitimate academic sub-discipline, shielded from non-mainstream or castaway science. Textbooks from four time-periods are examined: 1908–1935 (pre-professional stage); 1936–1963 (recruitment and expansion stage); 1964–1977 (normal science and crisis phase) and 1978–1991 (post-crisis phase). Results are discussed in terms of consensus formation, conceptual filtering and career gatekeeping, and the conservative versus innovative aspects of scientific progress.