A cultural universal (also called an anthropological universal or human universal) is an element, pattern, trait, or institution that is common to all known human cultures worldwide. Taken together, the whole body of cultural universals is known as the human condition. Evolutionary psychologists hold that behaviors or traits that occur universally in all cultures are good candidates for evolutionary adaptations. Some anthropological and sociological theorists that take a cultural relativist perspective may deny the existence of cultural universals: the extent to which these universals are "cultural" in the narrow sense, or in fact biologically inherited behavior is an issue of "nature versus nurture". Prominent scholars on the topic include Emile Durkheim, George Murdock, Claude Lévi-Strauss, and Donald Brown. In his book Human Universals (1991), Donald Brown defines human universals as comprising "those features of culture, society, language, behavior, and psyche for which there are no known exception", providing a list of hundreds of items he suggests as universal. Among the cultural universals listed by Donald Brown are: Linguistic universal Shelter Control of fire Tools, tool making Weapons, spear Containers Cooking Lever Rope The observation of the same or similar behavior in different cultures does not prove that they are the results of a common underlying psychological mechanism. One possibility is that they may have been invented independently due to a common practical problem. Outside influence could be an explanation for some cultural universals. This does not preclude multiple independent inventions of civilization and is therefore not the same thing as hyperdiffusionism; it merely means that cultural universals are not proof of innateness. Joseph H. Greenberg, et al. (1978) Universals of Human Language, 4 vols. Stanford University Press. Charles D. Laughlin and Eugene G. d'Aquili (1974) Biogenetic Structuralism. New York: Columbia University Press. Claude Lévi-Strauss (1966) The Savage Mind.