Human infants do not seem to be born with concepts of self or joint attention. One basic goal of Agency and Joint Attention is to unravel how these abilities originate. One approach that has received a lot of recent attention is social. Some argue that by virtue of an infant's intense eye gaze with her mother, she is able, by the age of four months, to establish a relationship with her mother that differentiates between "me" and "you." At about twelve months, the infant acquires the non-verbal ability to share attention with her mother or other caregivers. Although the concepts of self and...