Sustainable development as a subversive issue

Introduction

Sustainable development is an issue which has exercised the public mind for some years, even if few have a clear understanding of it. At one level, it is one of those fuzzy ideas that everyone is in favour of, because it means all things to all people. At another, it has a more concise conatation: it is about taking better care of the environment while ensuring economic growth. It is where ecology meets economics. But at its deepest level it can be argue that sustainable development is not a motherhood issue at all, it is a subversive issue.

The problem of sustainable development is really a stalking horse for the grand debate in which science is now involved with broader society, much as the contentious motion of the planets was Galileo's stalking horse over 350 years ago for the then-emerging science of dynamics, which led to the breathtaking, all-encompassing sweep of Newton's physics.

This is a debate about how we should understand difficult things. Scientists have not joined this debate with society since the Renaissance, when Galileo confronted the church, and argued for a new physics - argued that the physical world could be understood through a rational and material process which came to be called the scientific method. This, in the end, transformed society and swept away the Middle Ages. We now face a debate of similar proportions and consequence.

The grand debate

Sustainable development is subversive in exactly the same way that Galileo's dynamics was subversive - it intends to replace one way of thinking with another. It uses exactly the same strategy that Galileo used in the early decades of the seventeenth century. First, a nod of deference to the establishment to get standing, to get the necessary permission to air the argument. This is then followed by the unfolding of the argument, from its unexceptional premises to its ultimately destructive conclusion. Destructive, that is, of the status quo, of the established way of thinking.

Galileo was faced with all the power of the church, and he deferred to it. All his works carry the church's imprimatur. He argued from the world of experience, using his clever invention, the Galilean dialogue: a dialogue between the simple man who seeks to be put on the right path, and the learned man who stands for the status quo. Galileo's simple man, Simplicio, does not set out to destroy the established view, only to understand it by asking naive, but dangerous questions based on his own experience with the material world. Through this powerful tool, Galileo was able to engage the establishment in an argument that led inexorably to its overthrow.

In the same way, sustainable development engages the establishment in a debate which is seemingly on the establishment's terms. It uses a clever invention: the need to bring environmental and economic concerns together - an admirable goal, especially when also couched in terms of bringing the environment into the mainstream of political debate. Sustainable development is as much about deferring to the establishment in order to get standing as Galileo's trick of couching his argument as a dialogue was in getting his imprimaturs from his establishment, the church. Sustainable development is really about finding a palatable way to get a hearing for some very subversive ideas.

It is the Galilean dialogue of our times.

But what then is 'today's Galilean idea' and who is 'the establishment' - what is this new physics and who is the church?

Complexity - today's Galilean idea

Let me deal first with 'today's Galilean idea' by considering Newton's physics a little more closely.

The key to Newton's success lay in the simplicity of the systems, or better, the simplicity of the relationships he studied. The relationship between gravity and mass is simple and strong, so strong that it dominates the observable dynamics of celestial bodies. It is characterised by an inverse law. For all practical purposes, we need only consider the largest and nearest bodies when calculating the forces holding, say, the Earth in its orbit. Even though every other body in the universe affects the motion of the Earth, we can safely ignore nearly all of them except the Sun and perhaps a few of the planets. As a first approximation, Newton's laws explain the motions of stars, planets and apples with great economy and elegance.

As for gravitation, so also for radiation. Much of physics is governed by inverse laws. In a sense, the triumph of physics as an explanatory system is the triumph of explaining relatively simple systems to a first approximation. There are, of course, complex physical systems, but Newton's physics does not have much that is practical to say about them. Weather is an example. We can say that the weather is governed by relatively simple and well known physical laws, but the number of variables is so great that analytical solutions evade us. We cannot arrive at a useful first approximation to the weather in the same way we can describe and understand the motions of the planets.

If Newton's equations were simple and elegant, it was because the systems he studied were themselves simple and elegant. His genius was in seeing the underlying simplicity and similarity in the motions of planets and apples. But he left science with a terrible legacy because he was, in a sense, too successful. Newton's success encouraged the belief over the next couple of hundred years that the trick to science lay in finding clever ways to see through the apparent complexity of the natural world to its underlying simplicity - in reducing the complexity to its more fundamental simplicity.

One by one the simple systems have fallen to this approach: for example, in physics, the theory of electromagnetism; in chemistry, the theory of valency; and in biology, the theory of cells.

But this success left a knot of hard problems intractable to this reductionist approach. These were most obvious in biology: ecosystems, for example, must be more complex by several orders of magnitude than the weather.

These problems were most obvious in biology because, in contrast to the sway of inverse laws in physics, biology is conspicuously affected by exponential relationships. The ecologist who first enunciated 'The Tragedy of the Commons', Garrett Hardin, made the point eloquently in an essay 30 years ago on ecology as a subversive science:

'There could hardly be a more trifling physical event than dropping a single bacterium onto a human pharynx - the mass of one body is 18 orders of magnitude greater than that of the other. But if the bacterium is a living pathogen, and the pharyngeal membrane is susceptible to the disease, the consequence may literally be of world-shaking importance. A man may sicken and die, starting an epidemic that weakens an empire and changes the course of history. All this is possible. It is also possible that nothing of historical importance happens. The difference between the two extremes is connected with nothing a physicist would notice. The initial bacterium weighs only about 7 x 10 ^-14 grams in either case; the significant differences are infinitely subtle.'

While a physicist asks 'How big is it?' or 'How far away?', a biologist asks 'Does it increase exponentially?' or 'Is positive or negative feedback involved?'. To the biologist, nothing is, a priori, insignificant. There can be no Newtonian first approximation. The whole system must be considered.

It is not surprising that disciplines like ecology were the first to feel dissatisfied with the promise of simplicity implicit in the Newtonian tradition. Their complexity is irreducible in the sense that their systems are so closely intertwined, so closely interacting, that they cannot be studied sensibly through their simpler components. Unlike Newtonian systems, where first approximations can safely ignore small effects to create satisfactorily simple linear solutions, complex systems such as ecosystems, do not respond to first approximations.

To put it bluntly, linear dynamics best applied to the behaviour of simple systems composed of few entities, while more complex systems exhibit non-linear dynamics. The trouble is that most of the observed universe, from galaxies to societies to viruses, is more like the latter, more complex than simple.

Complex systems are messy. The equations describing them are generally not solvable, they generally do not move gracefully to equilibria, their behaviours are generally not predictable. And yet they are what the real world is made of. We need to understand them.

Thus the subversive idea, the Galilean idea that we need to take to the establishment is not the idea of sustainable development, it is the idea of complex systems. It is the idea that there exist many important systems for which simple, linear approaches - Newtonian approaches, if you like - do not work, and for which we must develop a new science.

Economics and the establishment

Now let us consider our establishment, our body politic. It is fair to say that it is suffused by economics. We may even say that economists take the place of priests in our secular society. Galileo would have had no difficulty recognising them as such, by the ways in which they infiltrate all the seats of power as leaders or advisors, in the ways in which they prophesy and prognosticate, but most of all in the ways in which they explain their unfulfilled prophesies after the event. Not for them what Galileo called his "wise, ingenuous and modest sentence, 'I know it not' ".

And what sort of economics do they preach? Here is the rub: the economists jumped too soon! At the end of the 19th century, economics adopted the sort of Newtonian mechanics that I have just argued cannot be useful in explaining complex systems. In a bid to become more 'scientific', they proposed that economies be thought of as if they were the simplest physical systems with a single point of stability, and governed by a strictly linear dynamics: the simplest kind of Newtonian dynamics.

The economists have even invented an 'invisible hand' to replace Newton's God to rule serenely over these mechanics, and have then packaged it all up into a central dogma called the 'general equilibrium theory'.

The words of Leon Walras, the 19th century originator of the theory, show clearly its scientific pretensions:

'... we all accept the current description of the universe of astronomical phenomena based on the principle of universal gravitation. Why should the description of the universe of economic phenomena based on the principle of free competition not be accepted in the same way?'

while the words of his successor, Vilfredo Pareto, confirm its essentially Newtonian cast:

'Let us go back to the equations which determine equilibrium. In seeing them somebody - it might be the writer - made an observation, 'These equations do not seem new to me, I know them well, they are old friends. They are the equations of rational mechanics'. That is why pure economics is a sort of mechanics or akin to mechanics.'

As this simplistic synthesis was occurring in economics, in the natural sciences, the opposite was happening. In the early years of the 20th century, the Newtonian certainty began to unravel. The Darwinian revolution had begun to bite, and the dominant roles of chance and history in the affairs of living things were becoming apparent. At the same time, Heisenberg's quantum mechanics showed that there were limits not only to Newtonian physics, but also to what could be known.

As a result, the awkward bits of science, the complex refractory bits of geology, chemistry, biology and so on that had been confined to taxonomy - science's attic - began to assert themselves, and new disciplines, such as ecology, emerged.

There were even rumblings in economics. The most prominent economic heretic [5], John Maynard Keynes lamented:

'The atomic hypothesis that has worked so splendidly in physics breaks down (in economics). We are faced at every turn with problems of organic unity, of discreteness, of discontinuity - the whole is not equal to the sum of the parts, comparisons of quantity fail us, small changes produce large effects, the assumptions of a uniform and homogeneous continuum are not satisfied.[6]'

But this self-evident complexity has not been sufficient to turn the broad church of economics from its defining idea [7]. Economics parodies Newtonian physics to create a linear equilibrial theory which ignores reality.

This would not be a problem if economists were just 'academic scribblers' as Keynes [8] called them, but economists have achieved what scientists have not: they are the gatekeepers of the establishment, and they can be expected to hold fast to their Newtonian universe even as science discards it.

The grand debate then is about replacing linear thinking with non-linear thinking in body politic. It is about replacing simple, outdated nostrums with more realistic approaches to the complexity of the real world. It is about the subversive idea that we can do better by acknowledging that we know less.

Handling surprise and visualising complexity

Where do environmental scientists, and, indeed, other scientists, fit in this? I believe they are preadapted for two reasons to taking a prominent role in this debate. They have two crucial, related talents: the ability to handle surprise and the ability to visualise.

The capacity to handle surprise is a key feature of every scientific profession - the surprise of discovery followed by learning: discovering the unexpected, and then learning from the discovery and incorporating that learning and understanding into the known. The unexpected, the unknown, always lies in wait of every environmental scientist just over the horizon of space and time. It conditions an early acceptance that the real world is more complex than one might have thought.

This acceptance of the complexity of the real world and the surprises it offers stand in contrast to the established view in economics which, being equilibrial, has neither history nor future. Equilibrial dynamics of the Newtonian type are eternal and unchanging. Only a few economists have accepted this fatal flaw in their general equilibrium theory. George Shackle is one:

'To acknowledge that there is novelty, in the sense of fundamentally undeducible things, waiting to be encountered for the first time, is to acknowledge that we cannot build models that will exhibit the course of a society's history over even a limited span of time.[9]

The willing acceptance of surprise puts environmental scientists in the vanguard with all those who seek to change the way we understand the world.

The other talent that many environmental scientists have is the ability to visualise. They are comfortable with maps.

Consider maps for a moment. They are intensely non-linear ways of capturing information. If you doubt this, imagine trying to describe a map in words - in its uttermost detail. As any land surveyor who remembers 'metes and bounds' descriptions can tell you, it is well nigh impossible, and any attempt to do so is much 'bigger' than the map itself. And what are words, but a linear way of capturing information?

In fact, human beings have invented two parallel and independent ways of capturing and transmitting information: words and maps. Maps form an authentic, independent non-linear tradition running in parallel to the development of the linear tradition of language and the written word.

And environmental scientists such as surveyors, since at least the time of the pharaohs, have been the key custodians of one of those traditions, the mapping tradition. This gives them a special place in the grand debate. They are the mappers, the visualisers of complex systems. They have been doing that for generations, making complex systems understandable, and the rest of science, and indeed society, has much to learn from them.

Let us think about maps and words a little more deeply. What can we say of the ascendency of words at the present time, indeed for such a long time that we instinctively equate literacy with education? The dominance of literacy is nothing more than the dominance of linear thinking, humankind's first response to understanding the world, humankind's first approximation of the real world.

Linear thinking and its attendant literacy are perfectly adequate for understanding much of the world. Indeed they have stood us in good stead for a long time. The first tens of thousands of years of human civilisation have been able to muddle along quite adequately using a linear approach to the world. But as we have uncovered and then learned from the surprises the world offers, we have begun to exhaust the possibilities of the linear approach. We have begun to run out of useful first approximations.

We are now uncovering surprises for which linear first approximations are neither useful nor productive - of which sustainable development is only the most plangent.

Complex systems

Fortunately this comes at a time when great strides have been made in the science of handling non-linear systems. New physics, new chemistry, new biology, new mathematics and, especially, new computation have come together to create a new discipline of complex systems.[10]

Complex systems is an emerging discipline with its own institutes and journals. It may look like a cross-over discipline that allows new approaches from physics, say the physics of spin glasses, to be used in modelling biological phenomena, or new biological insights, say from neurology or evolution, to be used in computer science as neural nets or genetic algorithms. This may have been so in its early years, the late 1970s and early 1980s perhaps, but such is the progress that has been made that it is becoming clear that complex systems is now more than a cross-over discipline, perhaps even more than a discipline - it is becoming a new way of doing science.

It might be thought that this is drawing too long a bow, to talk of a new way of doing science. But a strong argument may be made that science is transitting from one epoch to another through the science of complex systems.

Think of the development of science. Science added an instrument-based experimental approach to the dominant observational approach during the Renaissance, the time of Galileo, Harvey and Boyle. A mathematically-based theoretical approach was added in the period of the couple of centuries separating Newton from Einstein. These three traditions - observational, experimental, and theoretical - continue today to underpin science. But such is the accelerating pace of science, the latter part of this century is witnessing not one, but possibly two new approaches to science emerging to take their places alongside this historical triptych. Each of these new approaches is embedded in the science of complex systems.

The first of these newcomers is the computational approach, typified by the numerical modelling and simulation of things like aircraft, brains and ecosystems, their only similarity being their complexity, their non-linearity. Here typically the observational data are incomplete, the experimental data difficult to obtain and the theoretical underpinning inadequate, but progress can be made and understanding can be gained through the exploration of the behaviour of sufficiently realistic models. Again, typically, the results of these explorations are reports in highly visual terms, through the use of maps rather than words.

Observational, experimental and theoretical approaches depend on good instruments and tools: instruments like telescopes and microscopes, and tools like mathematics. The computational approach also depends on tools: computer software and hardware.

And it is these computing tools that have fostered the development of the second new approach to science: the interactive approach.

Increasingly, the scientists who study complex systems are coming to realise the importance of actively exploring dynamics by interacting with a realistic model of the system in real time: by engaging the system in a sort of dialogue. By shrinking or expanding the time and space scales of the observer to meet the model on equal terms, we create an observer of whom Heisenberg would be proud, one who is so enmeshed with the model that there is no input and output in the traditional sense, but rather an interaction, a dialogue, so novel that it is easy to suggest that this really is a new way of doing science.

This way of doing science depends on hardware and software in the same way that the computational approach does, but it goes further. It demands high performance computing - supercomputing - to make real time interaction possible, and it demands high end visualisation to provide a sufficiently realistic representation of the model to allow for effective interaction.

But if there are no traditional outputs, results or whatever, what is it that we report, that we communicate as a consequence of doing this sort of science? Traditionally, scientists report the results of their observations, or experiments, or the predictions of their theories as journal papers. Even with the computational approach, the simulation results are reported, though usually in highly visual ways. In interactive science, the model itself (with the instructions on how to use it) sitting on the internet becomes the report, the publication.

Conclusion

Science has changed society before. But perhaps never before has it attempted so profound a change.

The science of the Renaissance pushed man from his privileged position at the geographic centre of God's universe. Galileo, with his telescope, showed that we inhabit a tiny planet, orbiting an average star in an unremarkable galaxy, adrift in a vast impersonal cosmos.

The science of Darwin showed that man was not unique among God's creatures, but, like all other living things, an accident of fate, evolved by chance through natural selection, a process that Darwin described in a letter to the botanist Joseph Hooker as one of 'the clumsy, wasteful, blundering, low and horribly cruel works of nature'[11].

Now the science of complex systems threatens to remove our only remaining prop - our belief in our own intelligence - by showing that the real world is messy: its complexity irreducible, its history unknowable, and its future always surprising.

In this grand debate, there is only one place to be: on the side of change, on the side of science, however unsettling it may be. We may be comforted by the fact that our scientific forefathers also found the going hard. Even Galileo, under pressure from the Holy Office, recanted his belief that the earth moved around the sun. But, whatever the pressure we may find ourselves under, we can take heart from Galileo's larrikin [12], but sotto voce rejoinder: 'Eppur si muove' - 'But it does move'.[13]

Notes and references