Public debates about relativism often revolve around the frequently cited but unclear notion of cultural relativism. The idea that norms and values are born out of conventions can be traced back to the Greek historian Herodotus (c. 484–425 BC), but it is only in the 20th century, and particularly with the advent of social anthropology, that cultural relativism has gained wide currency. Franz Boas, responsible for the founding of social anthropology in the U.S., claimed that