November 19, 2017

Thermodynamics or ecodynamics?

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Scientists and philosophers – many of them sympathetic to the ecological movement – have seized on the Second Law of Thermodynamics and hailed it as the key to unravelling the secrets of the universe. But can the behaviour of the natural world really be understood through the law originally formulated to explain the workings of a steam engine?

Published in The Ecologist Vol. 11 No. 4, July–August 1981.

“Entropy” by Jeremy Rifkin and Ted Howard has been hailed as a new landmark in the study of what the Club of Rome calls the “predicament of Man”. Rufus Miles of Princeton Uni­versity describes it as “earth shaking in its implications” and compares Rifkin to Copernicus and Darwin. Hazel Henderson assures us that Rifkin and Howard “have written the epitaph of economics” and that their book provides a “major recon­ceptualisation which will help to shape the public debate of the 1980s.” I am afraid I can agree with none of these views.

This is not to say that this book does not have qualities. I think that it does state very succinctly and very clearly just how industrial man is destroying the planet on which he lives. It also tells us that there is no technological way out, as government experts still insist there is. The only solution to our problems is to phase out industrial society itself and phase in a new low-energy society – a thesis that is well known to many of our readers since it was first properly formulated in the pages of the Ecologist in our Blueprint for Survival (see here) in January 1972.

It is for a different reason, however, that this book is considered so important. It tries to explain what is happening to our society and it does so in a language that will impress many people – that of thermodynamics, which our scientists – the priests of industrialism – and in particular our physicists – the high priests – have ritually sanctified. Their thesis is that the fate of our economic system is sealed, by virtue of the fact that economic behaviour violates that most holy of all principles – the Second Law of Thermodynamics, or the Entropy Law.

This is of course primarily the thesis of Nicholas Georgescu Roegen whose papers we have published in The Ecologist since 1971, [1] not so much because I or any of my colleagues were sold on the Entropy thesis but because Georgescu Roegen is one of the first economists to have shown that economic behaviour must be governed by the laws that govern other forms of behaviour on this planet and not just by those very narrow ones that our economists have formulated. I part company with Georgescu and Rifkin when they include the Entropy Law in the former category, still more when they tell us, as most scientists do today, that it is the most fundamental of all such laws.

Before I defend my position, let me first try to explain what is the Entropy Law.

The Entropy Law

The term ‘entropy’ was coined by Rudolph Clausius in 1868. He observed that within a closed receptacle, heat differences tended to even out. The evening-out continued until total heat-uniformity was obtained. This uniformity could thus be regarded as a position of ‘equilibrium’ – at least from the thermodynamic point of view and he referred to it as ‘entropy’.

As Rifkin points out, however, the concept itself is much older. Sadi Carnot, a French engineer, first made use of it 41 years earlier. In trying to understand the workings of a steam engine, he realised that it was exploiting the heat difference between that part of the system which was hot and that which was cold. It was this difference in temperature that enabled the system “to do work”. This difference, however, tended to even out, and as this happened, so the system’s ability to do work was correspondingly reduced.

In such conditions, energy is said to have been dissipated – which means that it has degraded to a more homogeneous state – one that is identified with equilibrium or what Clausius called ‘entropy’.

This, in essence, is the Entropy Law, and it would be quite acceptable if it were applied strictly to the field of thermodynamics. The trouble, however, is that its use has been extended to apply to fields of behaviour that are very distant from thermodynamics and which would appear, to most sensible people, to be governed by very different laws from those that govern the behaviour of hot air in a closed receptacle or of steam in the boiler of a locomotive.

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The entropy cult

What has happened to the Entropy Law is what happened to many other scientific theories. It has become the object of a cult and taken to provide a key with which to unravel the secrets of the universe.

The same thing has occurred to Shannon and Weaver’s Information Theory, which was perfectly all right, so long as it was applied to the field of communications for which it was designed but which has only served to confuse everybody, after it was hailed as a great scientific discovery that would, among other things, provide a means of measuring biospheric complexity or organisation.

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Why does the Entropy Law not apply to the real world?

How then do we know that the Entropy Law does not apply to behaviour within the biosphere?

Well to begin with it is easy to see that it doesn’t. Life probably began on this planet 3 billion years ago and since then – that is until the beginning of the historical era a mere 10,000 years ago – it has not ceased to develop both in complexity, diversity and stability. [2] In other words it has behaved over what most sensible people would regard as a sufficient sample of time, in a manner that is diametrically opposed to that in which it should have behaved had it been governed by the Entropy Law.

This is a source of great embarrassment to our scientists. “How is it possible to understand life”, asks Brillouin, “when the whole world is ruled by such a rule as the second principle of thermodynamics which points towards death and annihilation?” [3] Indeed, either we are all mad and there has not been such a thing as evolution; and the biosphere with its myriad forms of life is an illusion; or else the Entropy Law does not apply to the behaviour of living things – only to that of hot air in a closed receptacle or steam in a locomotive.

Some of the most thoughtful philosophers of biology seem to realise this. Thus as Arthur Koestler writes:

“the Second Law applies only in the special case of so called ‘closed systems’ (such as a gas enclosed in a perfectly isolated container). But no such closed systems exist even in inanimate nature, and whether or not the universe as a whole is a closed system in this sense, is anybody’s guess. All living organisms, however are ‘open systems’, that is to say, they maintain their complex form and functions through continuous exchanges of energies and material with their environment. Instead of ‘running down’ like a mechanical clock that dissipates its energies through friction, the living organism is constantly ‘building up’ more complex substances from the substance it feeds on, more complex forms of energies from the energies it absorbs, and more complex patterns of information – perceptions, feelings, thoughts – from the input of its receptor organs.” [4]

Brillouin also realises this:

“Both principles of thermodynamics apply only to an isolated system, which is contained in an enclosure through which no heat can be transferred, no work can be done and no matter nor radiation can be exchanged.” [3]

The World on the other hand is not a closed system.

“It is constantly receiving energy and negative entropy from outside – radiant heat from the sun; gravitational energy from the sun and moon (provoking sea tides); cosmic radiation from unknown origin and so on.” In this way, the sentence to “death by confinement” is avoided by living in a world that is not a confined and closed system.” [3]

Von Bertalanffy notes the same thing. Because they live within an open system,

“living systems, maintaining themselves in a steady state, can avoid the increase of entropy, and may even develop towards states of increased order and organisation”. [5]

So too Waddington [6] regards the embryological process as a model for other biospheric processes. He notes that the embryo increases its complexity as it develops and for this and other reasons cannot believe

“[that] any serious embryologists have considered that the second law of thermodynamics could be applied in any simple way to their subject material, in spite of what classical physicists might say.”

Indeed, Waddington assures us that the most creative physicists of his day, people like Blacketh, Cockroft, Wilson and Dirck, would not have been tempted to impose the Entropy Law “as a rigid dogma of biology”. But is it only because the earth receives energy from the sun (i.e. because it is an open system) that the Entropy Law does not apply? There seem to be other reasons. After all, other celestial bodies are open systems just as is the planet earth. They are all bombarded with energy, “radiant heat from the sun, gravitational energy from the sun and moon, cosmic radiation etc.”

Another consideration leads one to the same conclusion. Even in a closed system, behaviour does not always occur as it should do were it governed by the Entropy Law. Thus if one puts a corpse in a closed receptacle, one would expect it to decompose into its component parts, hence moving towards that state of disorder which our aristo-scientists identify with entropy. However, it will not do so, unless we open our closed receptacle and let in some oxygen.

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The reductionists

It is not altogether surprising that other conditions should have to be satisfied, for it is difficult to believe that the development of the biosphere can be explained as the Entropy Law implies, simply in terms of energy. Can sensible people really believe, as Rifkin tells us, that “the Entropy Law . . . this supreme physical rule of the universe purveys every facet of our existence because everything is energy?”

This is an old myth which we can refer to as ‘energy-reductionism’. It originally appears to have come into being as a way of getting round the problems associated with the understanding of matter. The atomic theory of matter was controversial. Thermodynamics was supposed to be based on it. Carnot however showed that this science was independent of such a theory. It only involves energy changes. As Mason points out, this meant that

“thermodynamics could proceed without a theoretical model of the nature of matter, indeed it could proceed without the supposition that matter existed objectively.” [7]

Hence the ‘Energetik’ school which, like Rifkin, taught that the phenomena of nature were explicable in terms of the transformation of energy. As Oswald, the principal proponent of this view, wrote:

“What we hear originates in work done on the ear drum and the middle ear by the vibrations of the air. What we see is only radiant energy which does chemical work on the retina, that is perceived as light. From this standpoint the totality of nature appears as a series of spatially and temporally changing energies of which we obtain knowledge in proportion as they impinge on the body, and especially upon the sense organs fashioned for the reception of the appropriate energies.” [7]

Of course other writers (Pythagoras, Mayer) have told us that everything is number, while atomic reductionists like Francis Crick tell us that the world is exclusively made up of atoms. In reality, of course, it is the way these atoms are organised that is critical, while there is no reason to believe that atoms have any greater reality than the objects – tables, chairs, dung-beetles, fiddler-crabs or whatever – into which they are organised.

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The illusion of reductionism

It is only possible to maintain these various forms of reductionism if we limit our study to very simple inanimate objects like gasses and billiard balls. As soon as one looks at the behaviour of complex forms of life in the real world the illusory character of these theories is quickly revealed.

As Brillouin points out,

“For inert matter it suffices to know energy and entropy. For living organisms, we have to introduce the “food value” of products. Calories contained in coal and calories in wheat and meat do not have the same function. Food value must itself be considered separately for different categories of living organisms. Cellulose is a food for some animals, but others cannot use it. When it comes to vitamins or hormones, new properties of chemical compounds are observed, which cannot be reduced to energy or entropy. All these data remain rather vague, but they all seem to point towards the need for a new leading idea (call it principle or law) in addition to current thermodynamics, before these new classifications can be understood and typical properties of living organisms can be logically connected together . . .” [3]

It is easy to show that if a complex natural system is deprived of any of its basic constituents, whether it be energy, information or any of the basic chemicals of life, it will cease to function properly and will slowly disintegrate i.e. move in the direction of disorder, or what Rifkin would call entropy. Thus it would be more precise to talk of ‘energy-entropy’ which would enable us to distinguish this notion from that ‘information entropy’ and ‘materials entropy’.

We could then have a whole set of Entropy Laws, each one stating that, in the absence of a specific constituent, movement will be towards ‘general’ entropy. Such a law is implicit to Shannon and Weaver’s theory of information. As we shall see, Georgescu Roegen also formulated such a law with regards materials – the Fourth Law of Thermodynamics.

We can, of course, go much further still and subdivide materials entropy into carbon-entropy, phosphorous-entropy, water-entropy etc. – and so on for the essential irreplaceable ingredients of living things. All such concepts would be as valid as that of energy-entropy, about which people make so much fuss but they would be equally invalid once all the other conditions favouring biospheric development were satisfied, for then systems are either able to synthesise their own constituents or derive them from elsewhere in the quantities required.

The availability of these constituents then leads to a very strange, indeed what appears to be, unique phenomenon. They tend to organise themselves – not in a random or haphazard way as is suggested by Volterra [8], May [9], Mellanby [10], Prigogine [11], and many others, but in a highly directive way, for random organisation does not exist in the real world. [12]

Now, living things develop – successive thresholds are achieved which are referred to as ‘levels of organisation’. Each time one is achieved, new forms of behaviour appear, that are governed by laws that were not previously operative. At the most sophisticated levels of organisation, behaviour displays those features we associate with life and are governed by a set of laws that are quite unknown to the physicist and the chemist to the extent that their knowledge is derived for the study of behaviour at lower levels of organisation.

What is particularly relevant to the thesis of this review is that living things are capable of overcoming many of the constraints applying to the behaviour of simpler things. On this subject it is worth quoting Brillouin once more.

“Consider a living organism. It has special properties which enable it to resist destruction, to heal its wounds and to cure occasional sickness. This is very strange behaviour and nothing similar can be observed about inert matter. Is such behaviour an exception to the second principle? It appears so, at least superficially, and we must be prepared to accept a ‘life principle’ that would allow for some exceptions to the second principle. When life ceases and death occurs, the ‘life principle’ stops working, and the second principle regains its full power, implying demolition of the living structure. There is no more healing, no more resistance to sickness; the destruction of the former organism goes on unchecked and is completed in a very short time. Thus the conclusion, or question: what about life and the second principle? Is there not, in living organisms, some Power that prevents the action of the second Principle?” [3]

The notion that living things have some property that distinguishes them from inanimate things is referred to as ‘vitalism’. This property was once taken to be of a supernatural nature, as in the case of Aristotle’s ‘Entelechy’, or of Bergson’s ‘Elan Vital’. This notion of vitalism, as von Bertalanffy points out, however has been dead for a long time although “people continue to pour abuse on its carcass”. [5]

Vitalism is condemned for another reason. It implies that the world cannot be understood purely in terms of physics, which our physicists – who want to maintain their dominion over science, indeed over knowledge in general – cannot conceivably accept.

Vitalism in its modern form, simply implies that behaviour at that level of organisation achieved by living things displays features that were not present at the previous levels. As Waddington writes,

“the contrast is not so much between mechanism and vitalism but rather between mechanism and organicism.” [6]

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Overcoming energy constraints

Because of the way living things are organised they are capable of providing themselves with the energy they require to maintain their stability – green plants via photosynthesis and predators by consuming green plants. Significantly many economists and technologists, who see everything in terms of maximising production, tend to complain of the inefficiency of photosynthesis which only extracts a very small percentage of available energy from the atmosphere.

They fail to realise that plants extract, via photosynthesis, precisely the amount of energy that they need and no more; that which is required for the purposes of maintaining their structure and reproducing themselves i.e. of assuring their stability within the ecosystem of which they are part. Were they to fix more energy they would use up more nutrients in the soil than could be made available on a permanent basis, which would inevitably cause disequilibria leading to reduced stability.

A physicist might tell us that the sun’s energy has been dissipated, but the answer to this is “So what?” As far as a student of the biosphere is concerned this dissipation is required to power the development of living things and to increase their stability and that of the biosphere, (I go as far as this with Prigogine, but no further).

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