Cultural relativism is the idea that a person's beliefs, values, and practices should be understood based on that person's own culture, rather than judged against the criteria of another.
It was established as axiomatic in anthropological research by Franz Boas in the first few decades of the 20th century and later popularized by his students. Boas first articulated the idea in 1887: "...civilization is not something absolute, but ... is relative, and ... our ideas and conceptions are true only so far as our civilization goes." However, Boas did not coin the term.
The first use of the term recorded in the Oxford English Dictionary was by philosopher and social theorist Alain Locke in 1924 to describe Robert Lowie's "extreme cultural relativism", found in the latter's 1917 book Culture and Ethnology. The term became common among anthropologists after Boas' death in 1942, to express their synthesis of a number of ideas Boas had developed. Boas believed that the sweep of cultures, to be found in connection with any sub species, is so vast and pervasive that there cannot be a relationship between cultures and races. Cultural relativism involves specific epistemological and methodological claims. Whether or not these claims necessitate a specific ethical stance is a matter of debate. This principle should not be confused with moral relativism.
Herodotus (Histories 3.38) observes on the relativity of mores (νόμοι):
He mentions an anecdote of Darius the Great who illustrated the principle by inquiring about the funeral customs of the Greeks and the Callatiae, peoples from the extreme western and eastern fringes of his empire, respectively. They practiced cremation and funerary cannibalism, respectively, and were each dismayed and abhorred at the proposition of the other tribe's practices.