What Makes Humans Different?

Mature human cognition is complex and variable, both across contemporary cultures and over human history, but human cognitive development proceeds in a predictable and regular pattern in infants and young children. Here I ask whether studies of human infants provide insights into the origins and nature of uniquely human social cognitive capacities. Do the complex social judgments made by human adults develop from, and build on, simpler systems that are functional in infants? Do non-human animals share any of these systems, and therefore serve as models for studies of their development and functioning at multiple levels of analysis? If so, then why does human social reasoning appear to be so different from that of other animals? Recent research on human infants suggests tentative answers to these questions. Moreover, the research suggests that more definitive answers may lie within reach, through a multi-leveled, multi-species search for the core mechanisms by which humans navigate the social world.