Social Functions: Evolutionary and Non-Evolutionary Frank Hindriks Abstract. Social functionalism comes in two kinds, evolutionary and non-evolutionary. However, each faces a significant problem. The most prominent kind of non-evolutionary functionalism, rational choice functionalism, relies on value judgments to distinguish between institutions with and without a function, which makes it inadequate as an explanatory theory (the axiological problem). Evolutionary functionalism identifies culture with traits of individuals, behavioral or informational. Because of this, it fails to capture the complexity of institutions, in particular the interdependences and relations between their participants (the complexity problem). Solving these problems requires a richer theory of institutions, one that involves not only equilibria but also rules. First, I argue that rules provide for a non-arbitrary way to distinguish institutions that have a function from those that do not. Second, they help to do justice to their complexity: they capture their symbolic and normative features and account for social roles and material resources. Thus, it is possible to develop two adequate conceptions of social functions, which account for both the proliferation and the persistence of institutions. Keywords: axiological problem; cultural evolution; evolutionary theory; function; functionalism; institutions; persistence; rules; teleological problem; reproduction Acknowledgments: I gratefully thank Richard Lauer, Simon Lohse, Thomas Reydon and Martina Valković for their insightful comments. Forthcoming in Cultural Evolution and Social Ontology: Interdisciplinary Perspectives, edited by Martina Valković and Thomas Reydon, Routledge, London.