Conflict theory is a sociopolitical theory that originated with Karl Marx and argues that individuals and groups within society interact on the basis of conflict rather than agreement. Conflict theory has three assumptions: humans are self-interested, societies operate under perpetual scarcity of resources, and conflict is pervasive and unavoidable within social groups and between social groups. Conflict theory has sought to explain a wide range of social phenomena, including wars, revolutions, poverty, discrimination, and domestic violence. It ascribes most of the fundamental developments in human history, such as democracy and civil rights, to capitalistic attempts to control the masses (as opposed to a desire for social order) . Conflict theory is most commonly associated with Marxism, but it may also be associated with a number of other perspectives, including critical theory, feminist theory, postmodern theory, post-structural theory, and postcolonial theory. Conflict theory has been criticized for being too politicized by its association with Marx and its widespread use by advocates in numerous causes and movements. Critics also argue it downplays unity in society while taking a negative view of society.