In the
social sciences an open system is a process that exchanges material, energy, people, capital and information with its environment. French/Greek philosopher
Kostas Axelos argued that seeing the
"world system" as inherently open (though unified) would solve many of the problems in the social sciences, including that of
praxis (the relation of knowledge to practice), so that various social scientific disciplines would work together rather than create monopolies whereby the world appears only sociological, political, historical, or psychological. Axelos argues that theorizing a closed system contributes to
making it closed, and is thus a conservative approach. The
Althusserian concept of
overdetermination (drawing on Sigmund Freud) posits that there are always multiple causes in every event.
David Harvey uses this to argue that when systems such as
capitalism enter a phase of crisis, it can happen through one of a number of elements, such as gender roles, the relation to nature/the environment, or crises in accumulation. Looking at the crisis in accumulation, Harvey argues that phenomena such as
foreign direct investment,
privatization of state-owned resources, and
accumulation by dispossession act as necessary outlets when capital has overaccumulated too much in private hands and cannot circulate effectively in the marketplace. He cites the forcible displacement of Mexican and Indian peasants since the 1970s and the
1997 Asian financial crisis, involving "hedge fund raising" of national currencies, as examples of this.
Structural functionalists such as
Talcott Parsons and neofunctionalists such as
Niklas Luhmann have incorporated system theory to describe society and its components. The
sociology of religion finds both open and closed systems within the field of
religion. ==Thermodynamics==