*Earlier versions of this paper have been presented at the Rutgers Semantics Seminar, in April 2007, at the conference Concepts and Their Analysis, in Zürich, September 2008, organized by Christian Nimtz, and at the workshop On the Theory of Reference, in Helsinki 2008, organized by Panu Raatikainen. The authors are grateful for comments to the audiences on these occasions. We have been much helped by comments from Genoveva Martí, Dan López de Sa, Sören Häggqvist and Åsa Wikforss, and from an anonymous referee at Nous. The work has been supported by the Spanish Ministerio de Educación y Ciencia (grant no. SAB2006-0056), the Institut des Études Avancées IEA-Paris, and the Swedish Research Council VR (project nos. 2007-2271 and 2009-1195).