 Sanger was a proponent of negative eugenics, which aimed to improve human hereditary traits through social intervention by reducing the reproduction of those who were considered unfit.Sanger's view of eugenics was influenced by Havelock Ellis and other British eugenicists, who believed that environmentally acquired traits were inherited by one's progeny.She did not speak specifically to the idea of race or ethnicity being determining factors and "although Sanger articulated birth control in terms of racial betterment and, like most old-stock Americans, supported restricted immigration, she always defined fitness in individual rather than racial terms."