In this paper we argue that the hypothesis of the theory of mind advanced in cognitive science can be the basis not only of the social abilities which allow interaction among individ- uals, but also of the construction of social reality. The theory of mind is the attribution, via the agent metaphor, of mental attitudes, like beliefs and goals, to other agents. Analogously, we attribute mental attitudes to social entities, like groups, normative systems and organizations with roles. The agent metaphor explains the necessary abilities to deal with com- plex aspects of social behavior, like acting in a group, playing a role in an organization, and living in a reality organized in institutions which create regulative and constitutive norms to regulate behavior. To show the feasibility of this approach we provide a computational model of the construction of social reality based on multiagent systems.