  It is worth emphasizing the difference between methodological individualism, in Weber’s sense, and the older traditions of atomism (or unqualified individualism) in the social sciences. Many writers claim to find the origins of methodological individualism amongst economists of the Austrian School (especially Carl Menger), and doctrines articulated during the Methodenstreit of the 1880s (Udehn 2001). Others trace it back to Thomas Hobbes, and the “resolutive-compositive” method elaborated in the opening sections of the Leviathan (Lukes 1968, 119). Yet the distinctive character of this type of atomism was summed up quite clearly by Hobbes, with his injunction to “consider men as if but even now sprung out of the earth, and suddainly (like Mushromes) come to full maturity without all kind of engagement to each other” (1651, 8:1). The atomistic view is based upon the suggestion that it is possible to develop a complete characterization of individual psychology that is fully pre-social, then deduce what will happen when a group of individuals, so characterized, enter into interaction with one another. Methodological individualism, on the other hand, does not involve a commitment to any particular claim about the content of the intentional states that motivate individuals, and thus remains open to the possibility that human psychology may have an irreducibly social dimension. Thus one way of accentuating the difference between atomism and methodological individualism is to note that the former entails a complete reduction of sociology to psychology, whereas the latter does not.