Social psychology is only a bit older than 100 years, with most of the growth occurring during the past 6 decades. In discussing the discipline's history, it should be noted that there are two social psychologies, one in psychology and the other in sociology, with the larger of the two being the psychological branch. The central focus of psychological social psychology is how the individual responds to social stimuli, whereas sociological social psychology focuses on larger group or societal variables, such as people's socioeconomic status, their social roles, and cultural norms. Although there have been calls to merge the two branches into a single field—and even a joint psychology–sociology doctoral program at the University of Michigan from 1946 to 1967—their different orientations make it doubtful ...