Rüdin was influenced by his then brother-in-law, and long-time friend and colleague, Alfred Ploetz, who was considered the 'father' of racial hygiene and indeed had coined the term in 1895. This was a form of eugenics, inspired by social darwinism, which had gained some popularity internationally, as would the voluntary or compulsory sterilization of psychiatric patients, initially in America. Rüdin campaigned for this early on. At a conference on alcoholism in 1903, he argued for the sterilisation of 'incurable alcoholics', but his proposal was roundly defeated. In 1904, he was appointed co-editor in chief of the newly founded Archive for Racial Hygiene and Social Biology, and in 1905 was among the co-founders of the German Society for Racial Hygiene (which soon became International), along with Ploetz. He published an article of his own in Archives in 1910, in which he argued that medical care for the mentally ill, alcoholics, epileptics and others was a distortion of natural laws of natural selection, and medicine should help to clean the genetic pool.