Chaos theory trashes the notions of equilibrium.

In 'Human Brain and Psyche as Complex Systems' by Gerald Schueler in page 2, under the title 'Chaos Theory', mentions..

"1. Equilibrium. One of the findings of chaos theory is that complex systems that seem to be in equilibrium are not really in equilibrium. Systems damped by friction, and driven by some kind of energy input, while appearing to be at an equilibrium state, are not really at equilibrium at all. Tiny variations are present which can send the system into chaos at any time. Complex systems, require far-from-equilibrium conditions in order to maintain self-organization or growth (Cohen & Stewart, 1994; Gleick, 1987; Kellert, 1993; Prigogine & Stengers, 1984)."

Equilibrium. May be its usefulness is past and gone. Dwindling into oblivion? A concept whose properties do not, and are not supported by the currently held knowledge. Superseded and turned obsolete by other concepts risen, and its continued use only deters a deeper exploration in the phenomena. A conceptual baggage in need of being rid off. Imperative the need to be replaced by concepts that they are more in tune and in the gist of the phenomena to be explained. In its ashes the concept of 'dynamic' emerges.

Thoughts straight out of the inability of the concept to attain a clear definition. Complex systems seem or appear to be in equilibrium but they are not. The apparent nature of equilibrium relying upon what is seen and not what lies underneath, expressed by a variable external to a system under study, one that an external observer finds appropriate and defines, befitted to the lack of means during the time of its original usage was ever thought. As the deeper probing into the underlying nature of systems, any system, has been gradually enabled, reveals its inadequacies. Redundant, likewise, nonsensical the far-from-equilibrium reference as a requirement for complex systems. The dynamic nature of complex systems under the continuous subjection to incompatible forces, a constant source of tiny variations ever ready to kickstart a bout of chaos, to test all possible outcomes to its evolution to the next state of existence.

Nevertheless, incisive the attribution to chaos of self-organization and growth, systems driven to perfection, to wholeness complete, overriding the necessity of any equilibrium.