In recent years, this pessimistic interpretation of the second law has been challenged by a startling new theory. The Belgian Nobel Prize winner Ilya Prigogine and his collaborators have pioneered an entirely different interpretation of the classical theories of thermodynamics. There are some parallels between Boltzmann’s theories and those of Darwin. In both, a large number of random fluctuations lead to a point of irreversible change, one in the form of biological evolution, the other in that of the dissipation of energy, and evolution towards disorder. In thermodynamics, time implies degradation and death. The question arises, how does this fit in with the phenomenon of life, with its inherent tendency towards organisation and ever increasing complexity.

The law states that things, if left to themselves, tend towards increased entropy. In the 1960s, Ilya Prigogine and others realised that in the real world atoms and molecules are almost never “left to themselves”. Everything affects everything else. Atoms and molecules are almost always exposed to the flow of energy and material from the outside, which, if it is strong enough, can partially reverse the apparently inexorable process of disorder posited in the second law of thermodynamics. In fact, nature shows numerous instances not only of disorganisation and decay, but also of the opposite processes – spontaneous self-organisation and growth. Wood rots, but trees grow. According to Prigogine, self-organising structures occur everywhere in nature. Likewise, M. Waldrop concluded:

A laser is a self-organising system in which particles of light, photons, can spontaneously group themselves into a single powerful beam that has every photon moving in lockstep. A hurricane is a self-organising system powered by the steady stream of energy coming in from the sun, which drives the winds and draws rainwater from the oceans. A living cell – although much too complicated to analyse mathematically – is a self-organising system that survives by taking in energy in the form of food and excreting energy in the form of heat and waste.[49]

Everywhere in nature we see patterns. Some are orderly, some disorderly. There is decay, but there is also growth. There is life, but there is also death. And, in fact, these conflicting tendencies are bound up together. They are inseparable. The second law asserts that all of nature is on a one-way ticket to disorder and decay. Yet this does not square with the general patterns we observe in nature. The very concept of “entropy”, outside the strict limits of thermodynamics, is a problematic one.

“Thoughtful physicists concerned with the workings of thermodynamics realise how disturbing is the question of, as one put it, ‘how a purposeless flow of energy can wash life and consciousness into the world.’ Compounding the trouble is the slippery notion of entropy, reasonably well defined for thermodynamic purposes in terms of heat and temperature, but devilishly hard to pin down as a measure of disorder. Physicists have trouble enough measuring the degree of order in water, forming crystalline structures in the transition to ice, energy bleeding away all the while. But thermodynamic entropy fails miserably as a measure of the changing degree of form and formlessness in the creation of amino acids, of microorganisms, of self-reproducing plants and animals, of complex information systems like the brain. Certainly these evolving islands of order must obey the second law. The important laws, the creative laws, lie elsewhere.” (Gleick)[50]

The process of nuclear fusion is an example, not of decay, but of the building-up of the universe. This was pointed out in 1931 by HT Poggio, who warned the prophets of thermodynamic gloom against the unwarranted attempts to extrapolate a law that applies in certain limited situations on earth to the whole universe. “Let us not be too sure that the universe is like a watch that is always running down. There may be a rewinding.”[51]

The second law contains two fundamental elements – one negative and another positive. The first says that certain processes are impossible (e.g. that heat flows from a hot source to a cold one, never vice versa) and the second (which flows from the first) states that entropy is an inevitable feature of all isolated systems. In an isolated system all non-equilibrium situations produce evolution towards the same kind of equilibrium state. Traditional thermodynamics saw in entropy only a movement towards disorder. This, however, refers only to simple, isolated systems (e.g., a steam engine). Prigogine’s new interpretation of Boltzmann’s theories is far wider, and radically different.

Chemical reactions take place as a result of collisions between molecules. Normally, the collision does not bring about a change of state; the molecules merely exchange energy. Occasionally, however, a collision produces changes in the molecules involved (a “reactive collision”). These reactions can be speeded up by catalysts. In living organisms, these catalysts are specific proteins, called enzymes. There is every reason to believe that this process played a decisive role in the emergence of life on earth. What appear to be chaotic, merely random movements of molecules, at a certain point reach a critical stage where quantity suddenly becomes transformed into quality. And this is an essential property of all forms of matter, not only organic, but also inorganic.

Remarkably, the perception of oriented time increases as the level of biological organisation increases and probably reaches its culminating point in human consciousness.[52]

Every living organism combines order and activity. By contrast, a crystal in a state of equilibrium is structured, but inert. In nature, equilibrium is not normal but, to quote Prigogine “a rare and precarious state”. Non-equilibrium is the rule. In simple isolated systems like a crystal, equilibrium can be maintained for a long time, even indefinitely. But matters change when we deal with complex processes, like living things. A living cell cannot be kept in a state of equilibrium, or it would die. The processes governing the emergence of life are not simple and linear, but dialectical, involving sudden leaps, where quantity is transformed into quality.

“Classical” chemical reactions are seen as very random processes. The molecules involved are evenly distributed in space, and their spread is distributed “normally” i.e., in a Gauss curve. These kinds of reaction fit into the concept of Boltzmann, wherein all side-chains of the reaction will fade out and the reaction will end up in a stable reaction, an immobile equilibrium. However, in recent decades chemical reactions were discovered that deviate from this ideal and simplified concept. They are known under the common name of “chemical clocks”. The most famous examples are the Belousov-Zhabotinsky reaction, and the Brussels model devised by Ilya Prigogine.

Linear thermodynamics describes a stable, predictable behaviour of systems that tend towards the minimum level of activity possible. However, when the thermodynamic forces acting on a system reach the point where the linear region is exceeded, stability can no longer be assumed. Turbulence arises. For a long time turbulence was regarded as a synonym for disorder or chaos. But now, it has been discovered that what appears to be merely chaotic disorder on the macroscopic (large-scale) level, is, in fact, highly organised on the microscopic (small-scale) level.

Today, the study of chemical instabilities has become common. Of special interest is the research done in Brussels under the guidance of Ilya Prigogine. The study of what happens beyond the critical point where chemical instability commences has enormous interest from the standpoint of dialectics. Of particular importance is the phenomenon of the “chemical clock”. The Brussels model (nicknamed the “Brusselator” by American scientists) describes the behaviour of gas molecules. Suppose there are two types of molecules, “red” and “blue”, in a state of chaotic, totally random motion. One would expect that, at a given moment, there would be an irregular distribution of molecules, producing a “violet” colour, with occasional flashes of red or blue. But in a chemical clock, this does not occur beyond the critical point. The system is all blue, then all red, and these changes occur at regular intervals. According to Prigogine and Stengers:

Such a degree of order stemming from the activity of billions of molecules seems incredible, and indeed, if chemical clocks had not been observed, no one would believe that such a process is possible. To change colour all at once, molecules must have a way to ‘communicate’. The system has to act as a whole. We will return repeatedly to this key word, communicate, which is of obvious importance in so many fields, from chemistry to neurophysiology. Dissipative structures introduce probably one of the simplest physical mechanisms for communication.

The phenomena of the “chemical clock” shows how in nature order can arise spontaneously out of chaos at a certain point. This is an important observation, especially in relation to the way in which life arises from inorganic matter.

‘Order through fluctuations’ models introduce an unstable world where small causes can have large effects, but this world is not arbitrary. On the contrary, the reasons for the amplification of a small event are a legitimate matter for rational inquiry.

In classical theory, chemical reactions take place in a statistically ordered manner. Normally, there is an average concentration of molecules, with an even distribution. In reality, however, local concentrations appear which can organise themselves. This result is entirely unexpected from the standpoint of the traditional theory. These focal points of what Prigogine calls “self-organisation” can consolidate themselves to the point where they affect the whole system. What was previously thought of as marginal phenomena turn out to be absolutely decisive. The traditional view was to regard irreversible processes as a nuisance, caused by friction and other sources of heat loss in engines. But the situation has changed. Without irreversible processes, life would not be possible. The old view of irreversibility as a subjective phenomenon (a result of ignorance) is being strongly challenged. According to Prigogine irreversibility exists on all levels, both microscopic and macroscopic. For him, the second law leads to a new concept of matter. In a state of non-equilibrium, order emerges. “Non-equilibrium brings order out of chaos.”[53]

  1. Waldrop, M. Complexity, The Emerging Science at the Edge of Order and Chaos, pp. 33-4.

  2. Gleick, J. op. cit., p. 308.

  3. Lerner, E. op. cit., p. 139.

  4. Prigogine, I. and Stengers, I. op. cit., p. 298.

  5. Prigogine, I. and Stengers, I. op. cit., pp. 148, 206 and 287.