the social animal: the hidden sources of love, character, and achievement is a non-fiction book by american journalist david brooks, who is otherwise best known for his career with "the new york times". the book discusses what drives individual behavior and decision making. brooks goes through various academic topics such as sociology, psychology, and biology and attempts to summarize various discoveries— such as brain development in early life. the book continually refers to two fictional characters 'harold' and 'erica', used by brooks as examples of how people's emotional personality changes over time.