Complex systems have many elements interacting.
The patterns that form are complex and non-linear. Arthur noted that complexity is not a theory in itself, or even a body of literature, it is a change in the way science is conducted. The ability to discover and study complex systems has been made possible by desktop workstations. In the early 1980s, Arthur asserted, desktop computing power reached the point at which researchers had at their fingertips the power to create and fiddle with patterns that form with the interaction of certain agents. This created a seachange in the sciences from stasis to process, from equilibrium to dynamism.