Not only was Sir Francis Galton a famous geographer and statistician, he also invented "eugenics" in 1883. Eugenics, defined as the science of improving racial stock, was developed from a new heredity theory, conceived by Galton himself, and from the evolution theory of Charles Darwin, transposed to human society by Herbert Spencer. Galton's eugenics was a program to artificially produce a better human race through regulating marriage and thus procreation. Galton put particular emphasis on "positive eugenics", aimed at encouraging the physically and mentally superior members of the population to choose partners with similar traits. In 1904, he presented his ideas in front of a vast audience of physicians and scientists in London. His widely-publicized lecture served as the starting point for the development of eugenics groups in Europe and the United States during the first half of the 20th century.