<P> 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 a monopoly 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 could 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 Asian and South - East Asian financial crisis of 1997 - 8, involving "hedge fund raising" of national currencies, as examples of this . </P> <P> Structural functionalists such as Talcott Parsons and neofunctionalists such as Niklas Luhmann have incorporated system theory to describe society and its components . </P>

What characteristic is not a key feature of the 'open systems' model of management