Controversially, Camper is known for developing the theory of the facial angle, which he intended as a mathematical approach to portraiture and comparative anatomy. He measured facial structure using an angle formed between the nostril-ear line and the upper jaw-forehead line. From his own perspective, shaped by the aesthetic and anthropological views of 18th-century Europe, Camper arranged various groups along what he saw as a continuum of facial angles: placing Greco-Roman statues at the idealized end, followed by Europeans, then individuals from Asian and African populations, and finally orangutans.[4] A creationist and monogenist, Camper believed racial differences stemmed from environment, diet, and culture rather than inherent traits. He rejected notions of racial inferiority and argued for the equality of Africans and Europeans.[5] However, his posthumous publications were misinterpreted, with later anatomists such as Étienne Geoffroy Saint-Hilaire and Paul Broca distorting his findings to support racial hierarchies.[4] The placement of Africans near orangutans in his illustrations fueled pseudoscientific racial theories, despite his intent to disprove them. His work was ultimately used to justify prejudice, including slavery, in the 19th and 20th centuries.[5]

Camper passed away on April 7, 1789, in The Hague, Netherlands, at the age of 66. During his lifetime, Camper was among the most renowned scientists in Western Europe, recognized for his contributions to anatomy, surgery, and comparative anthropology.[6]