George Schuyler, a renowned and controversial black journalist of the Harlem Renaissance, and Josephine Cogdell, a blond, blue-eyed Texas heiress and granddaughter of slave owners, believed that intermarriage would "invigorate" the races, thereby producing extraordinary offspring. Their daughter, Philippa Duke Schuyler, became the embodiment of this theory. Able to read and write at the age of two and a half, a pianist at four, and a composer by five...