Eugenics, the worldwide movement, attempted to better the human gene pool through intentional breeding, which greatly affected the mentally ill. Because the science behind eugenics said mental illness was a herditary trait, eugenic sterilization prevented people with "weak minds" to reproduce, with the intended result of ridding the world of this disease. DeJarnette, along with numerous physicians in America, Britain, China, Germany, and France believed and practiced eugenics. Despite popular belief, DeJarnette, along with fellow doctors in America, advocated eugenics as a way of helping the patients. DeJarnette did not practice eugenic sterilization out of hatred or cruelty, but rather with hope and concern for his patients. Click here to learn what DeJarnette believed and why he argued sterilization gave patients basic rights.