The emergence of self.

Longitudinal and cross-sectioned investigations of children from three different cultural settings reveal the emergence of behaviors during the last half of the second year that imply the first appreciation of standards on prohibited actions, recognition of the ability to gain goals, and awareness of the self's feeling states. It was suggested that these competences were inevitable consequences of maturational changes in the central nervous system as long as children were growing in a world of objects and people. The foundations for a moral evaluation of aggression and self-consciousness appear to be universal milestones of the second year of life.