Psychology

Write an essay (less than 300 words) on whether a single overarching theory unifies the field of developmental psychology, and support your answer. What difference does it make to psychology whether developmental psychology (or any other area of psychology, such as personality or social psychology) has a unifying theory? What would have to happen for psychology, or even an area within psychology, to have a unifying theory? For example, what would individual psychologists have to do?