ABSTRACT
Intentionality, according to many philosophical accounts since Brentano, is the mark of the mental. The present chapter will approach varieties of intentionality from the point of view of developmental and comparative psychology. How do different forms of intentionality develop in human ontogeny? In particular, how do most basic forms of it emerge in early childhood? How does this development compare to that of other species, notably non-human primates? How far do commonalities go, and where might uniquely human capacities begin? And which of the latter might be foundational for uniquely human forms of social and cultural life? In pursuing such questions, the chapter will focus on shared intentionality and explore the idea that shared intentionality lies at the heart of uniquely human cognitive capacities and is an essential foundation of uniquely human social and cultural life.
