Eugenics is the improvement of the human population by controlled breeding. With that definition many things can be put under the category of Eugenics. Social Darwinism though, is the opposite of Eugenics. It is a theory that human population is based off of survival of the fittest and natural selection. Nazism is something that can be categorized under Eugenics because the beliefs of Germany during that time period was that the Aryan race was the best and therefore he selected those he believed to be of pure German descent and allowed them to breed and either killed those that he did not want to have children or placed them into concentration camps. He believed that the Aryan race was the best way to improve the human population and so