Abstract: Some theories of conformity hold that social equilibrium either standardizes inferences or promotes a shared understanding of conventions and norms among individuals with fixed heterogeneous preferences (belief mechanisms). Others depict tastes as fluid and hence subject to social influences (preference mechanisms). Belief mechanisms dominate discussions of conformity within economics, but preference mechanisms receive significant attention in other social sciences. This paper seeks to determine whether conformity is attributable to belief mechanisms or preference mechanisms by exploiting their distinctive implications for the process of convergence. Laboratory experiments suggest that economists have focused too narrowly on explanations for conformity involving belief mechanisms.