It is common to categorize social scientific theories as either individualistic or holistic, and to assume that they are opposites. This neat picture is not so much wrong as too simple. There are different versions of both doctrines, and some versions combine elements from both. In this article I distinguish a number of versions of methodological individualism that differ significantly in strength. The main divide is between strong versions of methodological individualism, which suggest that all social phenomena should be explained only in terms of individuals and their interaction, and weak versions of methodological individualism, which also assign an important role to social institutions and/or social structure in social science explanations.
