In his dissertation of 1775, the young Johann Friedrich Blumenbach did not accept the Linnaean classification that relegated albinos to troglodytes. He instead affirmed their fully human nature, arguing that they were suffering from a disease. Blumenbach reported that the skin of the two boys was white, except for an unusual redness of the face. Blumenbach had concluded by induction that albinism is a disease of the eye pigmentation correlated to the skin and its adnexa; Francesco Buzzi did so with an anatomical demonstration carried out on a European albino and physiological experiments on rabbits. The anthropological tradition inaugurated by Blumenbach stressed the universality of albinism, since it was an indirect proof of the unity of the human species. With recognition of the presence of albinism also among Europeans, the perception of albinos, Leucoaethiopes, Dondos and Kakerlakken changed among intellectuals.