Book excerpt: Having pioneered the concept in economics that institutions structure incentives, Douglass North's later work posed the question, in turn: what structures institutions? His approach explored the role of culture, norms, and ideas and eventually drew its focus on shared mental models as the basis of institutions. An ongoing literature takes up North's fundamental question. In this paper, we contribute to this literature by bringing together North's mental-models approach and the work of philosopher John Searle. Searle pioneered the concept in philosophy that institutions are constitutive rules, established through collective assignment of particular status to objects in the world. Drawing upon cognitive science research on knowledge, learning, and habituation, as well as computer science research on artificial intelligence, we develop Searle's framework to pose a simple yet general account of the cognitive origins of institutions and the implications of this link for social theory. Our framework reconciles the social science approach to institutions as regulative rules with the philosophy approach to institutions as constitutive rules. It also provides a basis for considering impediments to social interaction that arise when individuals possess conflicting normative ideas and affiliate into groups whose shared understandings appear to conflict.