"The Kallikak Family: A Study in the Heredity of Feeble-Mindedness" by Henry H. Goddard is a psychological study published in 1912. It traces two branches of one family descended from a Revolutionary War hero—one from his marriage, one from an illicit encounter—to argue that intelligence and morality are hereditary. The book became influential in American eugenics, though later research revealed significant factual inaccuracies that invalidate its conclusions about inherited mental disabilities. (This is an automatically generated summary.)