Autopoietic systems, then, are sovereign with respect to the constitution of identities and differences. They do not create a material world of their own. They presuppose other levels of reality. Human life, for example, presupposes the small scope of temperature in which water exists as a liquid. But whatever they use as identities and as differences is of their own making.
Social systems use communication as their particular mode of autopoietic reproduction.
Their elements are communications which are recursively produced and reproduced by a network of communications and which cannot exist outside of such a network. Communications are not 'living' units, they are not 'conscious' units, they are not 'actions'. This synthesis is produced by the network of communication, not by some kind of inherent power of consciousness, or by the inherent quality of the information. Structuralists have never been able to show how a structure can produce an event. At this point, the theory of autopoiesis offers a decisive advance.