Higgitt examines Isaac Newton's changing legacy during the nineteenth century. She focuses on 1820–1870, a period that saw the creation of the specialized and secularized role of the "scientist." At the same time, researchers gained better access to Newton's archives. These were used both by those who wished to undermine the traditional, idealised depiction of scientific genius and those who felt obliged to defend Newtonian hagiography. Higgitt shows how debates about Newton's character stimulated historical scholarship and led to the development of a new expertise in the history of science.