<Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (October 2013) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (October 2013) (Learn how and when to remove this template message) </Td> </Tr> <Table> <Tr> <Th> Sociology </Th> </Tr> <Tr> <Td> </Td> </Tr> <Tr> <Td> <Ul> <Li> History </Li> <Li> Outline </Li> <Li> Portal </Li> </Ul> </Td> </Tr> <Tr> <Th> Main theories </Th> </Tr> <Tr> <Td> <Ul> <Li> Conflict theory </Li> <Li> Structural functionalism </Li> <Li> Symbolic interactionism </Li> </Ul> </Td> </Tr> <Tr> <Th> Methods </Th> </Tr> <Tr> <Td> <Ul> <Li> Comparative </Li> <Li> Computational </Li> <Li> Critical theory </Li> <Li> Ethnography </Li> <Li> Ethnomethodology </Li> <Li> Historical </Li> <Li> Mathematical </Li> <Li> Network analysis </Li> <Li> Positivism </Li> <Li> Qualitative </Li> <Li> Quantitative </Li> </Ul> </Td> </Tr> <Tr> <Th> Subfields and other major theories </Th> </Tr> <Tr> <Td> <Ul> <Li> Conflict </Li> <Li> Criminology </Li> <Li> Culture </Li> <Li> Demography </Li> <Li> Development </Li> <Li> Deviance </Li> <Li> Economic </Li> <Li> Education </Li> <Li> Environmental </Li> <Li> Family </Li> <Li> Feminist sociology </Li> <Li> Gender </Li> <Li> Health </Li> <Li> Immigration </Li> <Li> Industrial </Li> <Li> Inequality </Li> <Li> Knowledge </Li> <Li> Law </Li> <Li> Literature </Li> <Li> Medical </Li> <Li> Military </Li> <Li> Organizational </Li> <Li> Political </Li> <Li> Race and ethnicity </Li> <Li> Religion </Li> <Li> Rural </Li> <Li> Science </Li> <Li> Social change </Li> <Li> Social constructionism </Li> <Li> Social movements </Li> <Li> Social psychology in sociology </Li> <Li> Stratification </Li> <Li> Technology </Li> <Li> Terrorism </Li> <Li> Urban </Li> </Ul> </Td> </Tr> <Tr> <Th> Browse </Th> </Tr> <Tr> <Td> <Ul> <Li> Bibliography </Li> <Li> By country </Li> <Li> Index </Li> <Li> Journals </Li> <Li> Organizations </Li> <Li> People </Li> <Li> Timeline </Li> </Ul> </Td> </Tr> <Tr> <Td> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> </Td> </Tr> </Table> <Tr> <Th> Sociology </Th> </Tr>

When did the study of social change begin