Piero Scaruffi(Copyright © 2013 Piero Scaruffi | Legal restrictions )
These are excerpts and elaborations from my book "The Nature of Consciousness"
The Belgian (but Russian-born) physicist Ilya Prigogine showed that all biological systems actually belong to the same class of systems: they are all dissipative systems.
Classical Physics describes the world as a static and reversible system that undergoes no evolution, whose information is constant in time. Classical Physics is the science of being. Thermodynamics, instead, describes an evolving world in which irreversible processes occur. Thermodynamics is the science of becoming.
The second law of Thermodynamics, in particular, describes the world as evolving from order to disorder, while biological evolution is about the complex emerging from the simple (i.e. order arising from disorder). While apparently contradictory, these two views show that irreversible processes are an essential part of the universe.
Furthermore, conditions far from equilibrium foster phenomena such as life that classical Physics does not cover at all.
Irreversible processes and non-equilibrium states turn out to be fundamental features of the real world.
Prigogine distinguishes between “conservative” systems (which are governed by the three conservation laws for energy, translational momentum and angular momentum, and which give rise to reversible processes) and “dissipative” systems (subject to flows of energy and/or matter). The latter give rise to irreversible processes.
The theme of science is order. Order can come either from equilibrium systems or from non-equilibrium systems that are sustained by a constant source (or, equivalently, by a persistent dissipation) of matter/energy. In the latter systems, order is generated by the flow of matter/energy. All living organisms (including the biosphere as a whole) are non-equilibrium systems.
Prigogine proved that, under special circumstances, the distance from equilibrium and the nonlinearity of a system drive the system to ordered configurations, i.e. create order. The science of being and the science of becoming describe dual aspects of Nature.
What is needed is a combination of factors that are exactly the ones found in living matter: a system made of a large collection of independent units which are interacting with each other; a flow of energy through the system that drives the system away from equilibrium; and nonlinearity. Nonlinearity expresses the fact that a perturbation of the system may reverberate and have disproportionate effects.
Non-equilibrium and nonlinearity favor the spontaneous development of self-organizing systems, which maintain their internal organization, regardless of the general increase in entropy, by expelling matter and energy in the environment.
When such a system is driven away from equilibrium, local fluctuations appear. This means that the system gets very unstable in some places. Localized tendencies to deviate from equilibrium are amplified. When a threshold of instability is reached, one of these runaway fluctuations is so amplified that it takes over as a macroscopic pattern. Order appears from disorder through what are initially small fluctuations within the system. Most fluctuations die along the way, but some survive the instability and carry the system beyond the threshold: those fluctuations "create" new form for the system. Fluctuations become sources of innovation and diversification.
Either the system collapses or it reorganizes. When it reorganizes, it can exhibit a higher degree of order.
The potentialities of nonlinearity are dormant at equilibrium but are revealed by non-equilibrium: multiple solutions appear and therefore diversification of behavior becomes possible.
Technically speaking, nonlinear systems driven away from equilibrium can generate instabilities that lead to “bifurcations” (and “symmetry breaking” beyond bifurcation). When the system reaches the bifurcation point, it is impossible to determine which path it will take next. Chance rules. Once the path is chosen, determinism resumes.
The multiplicity of solutions in nonlinear systems can even be interpreted as a process of gradual "emancipation" from the environment.
Most of Nature is made of such “dissipative” systems, of systems subject to fluxes of energy and/or matter. Dissipative systems conserve their identity thanks to the interaction with the external world. In dissipative structures, non-equilibrium becomes a source of order.
In general, self-organization is the spontaneous emergence of ordered structure and behavior in open systems that are in a state far from equilibrium described mathematically by nonlinear equations.
These considerations apply to living organisms, which are prime examples of dissipative structures in non-equilibrium. Prigogine's theory explains how life can exist and evolution can work towards higher and higher forms of life. A “minimum entropy principle” characterizes living organisms: stable near-equilibrium dissipative systems minimize their rate of entropy production.
Catastrophe and chaos theories are special cases of nonlinear non-equilibrium systems.
Back to the beginning of the chapter "Self-organization and the Science of Emergence" | Back to the index of all chapters