The study of gifted children and adults first began in earnest in the 1860s with Francis Galton. After Francis Galton's Hereditary Genius (1869), no scientific investigations were conducted as to the nature of high intellectual ability until Terman's work. Galton surmised that genius runs in families, is hereditary. He sought men of accomplishment in order to discern whether or not they came from families full of eminent men. In the society of Britain's 1860s, however, it would be difficult to distinguish between the connections and opportunities of social class and raw, innate, inherited intelligence, something Galton did not attempt to do. Also, Galton's study did not address the incidence of unsuccessful members of the same families, and logically, he did not attempt to ascertain the different precursors to success or failure of members of the same family.