Sociology of knowledge is the study of how social contexts and structures influence human thought. It presumes that knowledge has a social component and is shaped by economic, religious, political and other social interests. Early thinkers like Vico and Marx recognized the role of society in shaping beliefs, though Marx's view that all knowledge is distorted by class interests is now seen as untenable. Durkheim argued that perception and experience are derived from social structures, which may be true for simple societies but not complex ones. The foundations of sociology of knowledge were established by Karl Mannheim in the 1930s and 1950s as he tried to systematically address the relationship between society and knowledge, though the problems it raises remain largely unsolved.