Environmental News From China

13 August, 2011

I was unable to access this blog last week while I was in Changchun—sorry!

But I’m back in Singapore now, so here’s some news, mostly from the 2 August 2011 edition of China Daily, the government’s official English newspaper. As you’ll see, they’re pretty concerned about environmental problems. But to balance the picture, here’s a picture from Changbai Mountain, illustrating the awesome beauty of the parts of China that remain wild:

The Chinese have fallen in love with cars. Though less than 6% of Chinese own cars so far, that’s already 75 million cars, a market exceeded only by the US.

The price of real estate in China is shooting up—but as car ownership soars, you’ll have to pay a lot more if you want to buy a parking lot for your apartment. The old apartments don’t have them. In Beijing the average price of a parking lot is 140,000 yuan, which is about $22,000. In Shanghai it’s 150,000 yuan. But in fancy neighborhoods the price can be much higher: for example, up to 800,000 yuan in Beijing!

For comparison, the average salary in Beijing was 36,000 yuan in 2007—and the median is probably much lower, since there are lots of poor people and just a few rich ones. On top of that, I bet this figure doesn’t include the many undocumented people who have come from the countryside to work in Beijing. The big cities in China are much richer than the rest of the country: the average salary throughout the country was 11,000 yuan, and the average rural wage was just 3,600 yuan. This disparity is causing young people to flood into the cities, leaving behind villages mostly full of old folks.

Thanks to intensive use of coal, increasing car ownership and often-ignored regulations, air quality is bad in most Chinese cities. In Changchun, a typical summer day resembles the very worst days in Los Angeles, where the air is yellowish-grey except for a small blue region directly overhead.

In a campaign to improve the air quality in Beijing, drivers are getting subsidized to turn in cars made in 1995 or earlier. As usual, it’s the old clunkers that stink the worst: 27% of the cars in Beijing are over 8 years old, but they make 60% of the air pollution. The government is hoping to eliminate 400,000 old cars and cut the emission of nitrogen oxide by more than 10,000 tonnes per year by 2015.

But this policy is also supposed to stoke the market for new automobiles. That’s a bit strange, since Beijing is a huge city with massive traffic jams—some say the worst in the world! As a result, the government has taken strong steps to limit car sales in Beijing.

In Beijing, if you want to buy a car, you have to enter a lottery to get a license plate! Car sales have been capped at 240,000 this year, and for the first lottery people’s chances of winning were just one in ten:

• Louisa Lim, License plate lottery meant to curb Beijing traffic, Morning Edition, 26 January 2011.

Why is the government trying to stoke new car sales in Beijing while simultaneously trying to limit them? Maybe it’s just a rhetorical move to placate the car dealers, who hate the lottery system. Or maybe it’s because the government makes money from selling cars: it’s a state-controlled industry.

On another front, since July there has been a drought in the provinces of Gansu, Guizhou and Hunan, the Inner Mongolia autonomous region, and the Ningxia Hui autonomous region, which is home to many non-Han ethnic groups including the Hui. It’s caused water shortages for 4.3 million people. In some villages all the crops have died. Drought relief agencies are sending out more water pumps and delivering drinking water.

In Gansu province, at least, the current drought is part of a bigger desertification process.

Once they grew rice in Gansu, but then they moved to wheat:

• Tu Xin-Yi, Drought in Gansu, Tzu Chi, 5 January 2011.

China is among the nations that are experiencing severe desertification. One of the hardest hit areas is Gansu Province, deep in the nation’s heartland. The province, which includes parts of the Gobi, Badain Jaran, and Tengger Deserts, is suffering moisture drawdown year after year. As water goes up into the air, so does irrigation and agriculture. People can hardly make a living from the arid land.

But the land was once quite rich and hospitable to agriculture, a far cry from what greets the eye today. Ruoli, in central Gansu, epitomizes the big dry-up. The area used to be verdant farmland where, with abundant rainfall, all kinds of plants grew lush and dense; but now the land is dry and yields next to nothing. All this dramatic change has come about in just 50 years—lightning-fast, a mere blink of an eye in geological terms.

Rapid desertification is forcing many parties, including the government, to take action. Some residents have moved away to seek better livelihoods elsewhere, and the government offers incentives for people to relocate to the lowlands Tzu Chi built a new village to accommodate some of these migrants.

Tzu Chi is a Buddhist organization with a strong interest in climate change. The dramatic change they speak of seems to be part of a longer-term drying trend in this region. Here is one of a series of watchtowers near Dunhuang, once a thriving city at the eastern end of the Silk Road. I don’t think this area was such a desert back then:

Meanwhile, down in southern China, the Guanxi Zhuang autonomous region is seeing its worst electricity shortage in the last 2 decades, with 30% of the demand for electric power unmet, and rolling blackouts. They blame the situation on a shortage of coal and the fact that the local river isn’t deep enough to provide hydropower.

On the bright side, China is investing a lot in wind power. Their response to the financial crisis of of 2009 included $220 billion investment in renewable energy. Baoding province is now one of the world’s centers for producing wind turbines, and by 2020 China plans to have 100 gigawatts of peak wind power online.

That’s pretty good! Remember our discussion of Pacala and Socolow’s stabilization wedges? The world needs to reduce carbon emissions by roughly 10 gigatonnes per year by about 2050 to stay out of trouble. Pacala and Socolow call each 1-gigatonne slice of this carbon pie a ‘wedge’. We could reduce carbon emissions by one ‘wedge’ by switching 700 gigawatts of coal power to 2000 gigawatts of peak wind power. Why 700 of coal for 2000 of wind? Because unfortunately most of the time wind power doesn’t work at peak efficiency!

So, the Chinese plan to do 1/20 of a wedge of wind power by 2020. Multiply that effort by a factor of 200 worldwide by 2050, and we’ll be in okay shape. That’s quite a challenge! Of course we won’t do it all with wind.

And while the US and Europe are worried about excessive government and private debt, China is struggling to figure out how to manage its vast savings. China has a $3.2 trillion foreign reserve, which is 30% of the world’s total. The fraction invested in the US dollars has dropped from 71% in 1999 to 61% in 2010, but that’s still a lot of money, so any talk of the US defaulting, or a drop in the dollar, makes the Chinese government very nervous. This article goes into a bit more detail:

• Zhang Monan, Dollar depreciation dilemma, China Daily, 2 August 2011.

In a move to keep the value of their foreign reserves and improve their ratio of return, an increasing number of countries have set up sovereign wealth funds in recent years, especially since the onset of the global financial crisis. So far, nearly 30 countries or regions have established sovereign wealth funds and the total assets at their disposal amounted to $3.98 trillion in early 2011.

Compared to its mammoth official foreign reserve, China has made much slower progress than many countries in the expansion of its sovereign wealth funds, especially in its stock investments. Currently, China has only three main sovereign wealth funds: One with assets of $347.1 billion is managed by the Hong Kong-based SAFE Investment Co Ltd; the second, with assets of $288.8 billion, is managed by the China Investment Corporation, a wholly State-owned enterprise engaging in foreign assets investment; the third fund of $146.5 billion is managed by the National Social Security Fund.

From the perspective of its investment structure, China’s sovereign wealth funds have long attached excessive importance to mobility and security. For example, the China Investment Corporation has invested 87.4 percent of its funds in cash assets and only 3.2 percent in stocks, in sharp contrast to the global average of 45 percent in stock investments.

What’s interesting to me is that on the one hand we have these big problems, like global warming, and on the other hand these people with tons of money struggling to find good ways to invest it. Is there a way to make each of these problems the solution to the other?

Rationality in Humans and Monkeys

15 July, 2011

Cosma Shalizi wrote a great review of this book:

• David Easley and Jon Kleinberg, Networks, Crowds and Markets: Reasoning about a Highly Connected World, Cambridge University Press, Cambridge, 2010.

Apparently this is one of the first systematic textbooks on network science, which Shalizi defines as:

the study of networks of semiautonomous but interdependent units and of the way those networks shape both the behavior of individuals and the large-scale patterns that emerge from small-scale interactions.

This is not quite the same as what I’ve been calling network theory, but I’d like to see how they fit together.

Shalizi’s review includes a great putdown, not of the book’s authors, but of the limitations of a certain concept of ‘rationality’ that’s widely used in economics:

What game theorists somewhat disturbingly call rationality is assumed throughout—in other words, game players are assumed to be hedonistic yet infinitely calculating sociopaths endowed with supernatural computing abilities.

Clearly we have to go beyond these simplifying assumptions. There’s a lot of work being done on this. One important approach is to go out and see what people actually do in various situations. And another is to compare it to what monkeys will do in the same situations!

Monkey money

Here’s a video by Laurie Santos, who has done just that:

First she taught capuchin monkeys how to use money. Then, she discovered that they make the same mistakes with money that people do!

For example, they make different decisions in what mathematically might seem like the same situation, depending on how it’s framed.

Suppose I give you $1000, and then ask which game would you rather play:

1) a game where I give you either $1000 more or nothing more, with equal odds.

2) a game where I always give you $500 more.

Most people prefer game 2), even though the average, or expected amount of money collected is the same in both games. We say such people are risk averse. Someone who loves to gamble might prefer game 1).

Like people, most capuchin monkeys chose game 2), although Santos used grapes rather than money in this particular experiment.

So, like people, it seems monkeys are risk averse. This is not a ‘mistake': there are good reasons to be risk averse.

On other hand, suppose I give you $2000 — twice as much as before! Feel all those crisp bills… think about all the good stuff you can buy. Now, which game would you rather play:

1′) a game where I either take away $1000 or nothing, with equal odds.

2′) a game where I always take away $500.

Most people prefer game 1′). The strange thing is that mathematically, the overall situation is isomorphic to the previous one. It’s just been framed in a different way. The first situation seems to be about ‘maximizing gains’. The second seems to be about ‘minimizing losses’. In the second situation, people are more likely to accept risk, in the hopes that with some chance they won’t lose anything. This is called loss aversion.

Monkeys, too, prefer game 1′).

This suggests that loss aversion is at least 35 million years old. It’s survived a long process of evolution! To me that suggests that while ‘irrational’, it’s probably a useful heuristic in most situations that commonly arise in primate societies.

Laurie Santos has a slightly different take on it. She says:

It was Camus who once said that man is the only species who refused to be what he really is. But the irony is that it might only be by recognizing our limitations that we can really actually overcome them.

Does economics elude mathematical reasoning?

For yet another approach the enormous project of reconciling economics to the reality of human behavior, see:

• Yanis Varoufakis, Foundations of Economics: A beginner’s companion, Routledge, London, 1998.

• Yanis Varoufakis, Joseph Halevi and Nicholas J. Theocarakis, Modern Political Economics: Making Sense of the Post-2008 World, Routledge, London, 2011.

For the introduction of the first book go here. The second is described on the Routledge website:

The book is divided into two parts. The first part delves into every major economic theory, from Aristotle to the present, with a determination to discover clues of what went wrong in 2008. The main finding is that all economic theory is inherently flawed. Any system of ideas whose purpose is to describe capitalism in mathematical or engineering terms leads to inevitable logical inconsistency; an inherent error that stands between us and a decent grasp of capitalist reality. The only scientific truth about capitalism is its radical indeterminacy, a condition which makes it impossible to use science’s tools (e.g. calculus and statistics) to second-guess it. The second part casts an attentive eye on the post-war era; on the breeding ground of the Crash of 2008. It distinguishes between two major post-war phases: The Global Plan (1947-1971) and the Global Minotaur (1971-2008).

The emphasis is mine here, not because I’m sure it’s true, but because of how important it could be. It seems quite plausible to me. People seem able to squirm out of any mathematical framework we set up to describe them, short of the laws of physics. Still, I’d like to see the book’s argument. If there’s a ‘logical inconsistency’ in something, I want to actually see it.

You can get a bit more feeling for the second book in a blog post by Varoufakis. Among other things, he makes a point reminiscent of one that Phil Henshaw has repeatedly hammered home here:

Imagine a theorist that tries to explain complex evolving ecosystems by means of engineering models. What would result but incongruity and a mindset bent on misunderstanding the essence of the explanandum; a flight from that which craves explanation?

(By the way: I thank Mike Stay and Miguel Carrión-Álvarez for pointing out some items that appear in this blog entry. They did this on Google Plus. More on that later, maybe.)

Food Price Spike

9 July, 2011

Back in 2007, food prices surged. Millions went hungry, and there were riots from Egypt to Haiti and Cameroon to Bangladesh. In 2008 they dropped, but starting at the beginning of 2009 they’ve been going up, and now they’re staying high:

This graph shows the “food price index”, which is a weighted average of food commodity prices. The exact formula seems to be a carefully guarded secret… well, at least they don’t make it easy to find!

Here’s a more long-term picture:

taken from here:

• United Nations Environmental Programme, The Environmental Food Crisis, 2008.

What’s been happening since 2000? You can blame the rising world population, but that’s not something that suddenly hit us at the turn of the century. People point to many causes, including:

1) A growing middle class in India and China, eating more—including more meat, which pushes up grain prices. For example, according to the Economist, the average Chinese consumer ate 20 kilograms of meat in 1985, but 50 kilos of the stuff in 2007. If you consider the population of China, that’s a lot more meat!

2) The use of grain and other foodstuffs for biofuels, heavily subsidized by some governments like the US, has increased competition for grain and, perhaps worse, created a tighter link between oil prices and food prices. If the price of oil goes up, gasoline costs more, so people can charge more for ethanol, so grain prices go up!

One small piece of good news: the US federal budget crisis is making more people consider cutting grain ethanol subsidies. But it hasn’t happened yet: don’t underestimate the power of the corn lobby.

3) More weather disasters, like the heat wave that caused Russia to halt grain exports last year, or the drought in Brazil that’s pushing up sugar prices now, or the drought in India that set sugar prices soaring in the summer of 2009.

People like to argue about whether these weather disasters are really increasing, and whether they’re really due to climate change. It remains hard to prove. Some people, like Al Gore, have already made up their minds. On 20 June 2011, he said:

Look what’s happened in the last twelve months:

– The twenty million people displaced in Pakistan, a nuclear-armed country, one of the biggest flood events in their history.

– An area of Australia the size of France and Germany combined, flooded.

– The nation of Colombia, they’ve had five to six times the normal rainfall. Two million people are still homeless. Most of the country was underwater for a portion of last year.

– My hometown, my home city of Nashville, a thousand-year flood. Thousands of my neighbors lost their homes and businesses. They had no flood insurance because there had never been a flood in areas that were flooded.

– Drought. Russia, biggest drought in their history, biggest fires in their history, over 50,000 people killed, and then all of their wheat and other food crops, along with that of Ukraine and Kazakhstan, taken off the world markets, leading to an all-time record spike in food prices.

– Texas, right now. The drought raised from “extreme” to “exceptional.” 254 counties in Texas, 252 of them were filed in the major disaster.

– Today, biggest fire in the history of Arizona, spreading to New Mexico.

– Today, biggest flood in the history of the Mississippi River valley underway right now.

At what point is there a moment where we say, ‘Oh, we ought to do something about this?’

A growing world middle class, the rising use of food for fuel, the effects of climate change… when it comes to rising food prices, there are lots of other causes one can point to.

But the big question is whether it’s a matter of many small causes that coincidentally happen to be boosting food prices now, or something more systematic.

In other words, is our world civilization hitting the limits of what the planet can support?

This Week’s Finds (Week 315)

27 June, 2011

This is the second and final part of my interview with Thomas Fischbacher. We’re talking about sustainable agriculture, and he was just about to discuss the role of paying attention to flows.

JB: So, tell us about flows.

TF: For natural systems, some of the most important flows are those of energy, water, mineral nutrients, and biomass. Now, while they are physically real, and keep natural systems going, we should remind ourselves that nature by and large does not make high level decisions to orchestrate them. So, flows arise due to processes in nature, but nature ‘works’ without being consciously aware of them. (Still, there are mechanisms such as evolutionary pressure that ensure that the flow networks of natural ecosystems work—those assemblies that were non-viable in the long term did not make it.)

Hence, flows are above everything else a useful conceptual framework—a mental tool devised by us for us—that helps us to make sense of an otherwise extremely complex and confusing natural world. The nice thing about flows is that they reduce complexity by abstracting away details when we do not want to focus on them—such as which particular species are involved in the calcium ion economy, say. Still, they retain a lot of important information, quite unlike some models used by economists that actually guide—or misguide—our present decision-making. They tell us a lot about key processes and longer term behaviour—in particular, if something needs to be corrected.

Sustainability is a complex subject that links to many different aspects of human experience—and of course the non-human world around us. When confronted with such a subject, my approach is to start by asking: ‘what I am most certain about’, and use these key insights as ‘anchors’ that set the scene. Everything else must respect these insights. Occasionally, some surprising new insight forces me to reevaluate some fundamental assumptions, and repaint part of the picture. But that’s life—that’s how we learn.

Very often, I find that those aspects which are both useful to obtain deeper insights and at the same time accessible to us are related to flows.

JB: Can you give an example?

TF: Okay, here’s another puzzle. What is the largest flow of solids induced by civilization?

JB: Umm… maybe the burning of fossil fuels, passing carbon into the atmosphere?

TF: I am by now fairly sure that the answer is: the unintentional export of topsoil from the land into the sea by wind and water erosion, due to agriculture. According to Brady & Weil, around the year 2000, the U.S. annually ‘exported’ about 4×1012 kilograms of topsoil to the sea. That’s roughly three cubic kilometers, taking a reasonable estimate for the density of humus.

JB: Okay. In 2007, the U.S. burnt 1.6 × 1012 kilograms of carbon. So, that’s comparable.

TF: Yes. When I cross check my number combining data from the NRCS on average erosion rates and from the CIA World Factbook on cultivated land area, I get a result that is within the same ballpark, so it seems to make sense. In comparison, total U.S. exports of economic goods in 2005 were 4.89×1011 kilograms: about an order of magnitude less, according to statistics from the Federal Highway Administration.

If we look at present soil degradation rates alone, it is patently clear that we see major changes ahead. In the long term, we just cannot hope to keep on feeding the population using methods that keep on rapidly destroying fertility. So, we pretty much know that something will happen there. (Sounds obvious, but alas, thinking of a number of discussions I had with some economists, I must say that, sadly, it is far from being so.)

What actually will happen mostly depends on how wisely we act. The possibilities range from nuclear war to a mostly smooth swift transition to fertility-building food production systems that also take large amounts of CO2 out of the atmosphere and convert it to soil humus. I am, of course, much in favour of scenarios close to the latter one, but that won’t happen unless we put in some effort—first and foremost, to educate people about how it can be done.

Flow analysis can be an extremely powerful tool for diagnosis, but its utility goes far beyond this. When we design systems, paying attention to how we design the flow networks of energy, water, materials, nutrients, etc., often makes a world of a difference.

Nature is a powerful teacher here: in a forest, there is no ‘waste’, as one system’s output is another system’s input. What else is ‘waste’ but an accumulation of unused output? So, ‘waste’ is an indication of an output mismatch problem. Likewise, if a system’s input is not in the right form, we have to pre-process it, hence do work, hence use energy. Therefore, if a process or system continually requires excessive amounts of energy (as many of our present designs do), this may well be an indication of a design problem—and could be related to an input mismatch.

Also, the flow networks of natural systems usually show both extremely high recycling rates and a lot of multi-functionality, which provides resilience. Every species provides its own portfolio of services to the assembly, which may include pest population control, creating habitat for other species, food, accumulating important nutrients, ‘waste’ transformation, and so on. No element has a single objective, in contrast to how we humans by and large like to engineer our systems. Each important function is covered by more than one element. Quite unlike many of our past approaches, design along such principles can have long-term viability. Nature works. So, we clearly can learn from studying nature’s networks and adopting some principles for our own designs.

Designing for sustainability with, around, and inspired by natural systems is an interesting intellectual challenge, much like solving a jigsaw puzzle. We cannot simultaneously comprehend the totality of all interactions and relations between adjacent pieces as we build it, but we keep on discovering clues by closely studying different aspects: form, colour, pattern. If we are on the right track, and one clue tells us how something should fit, we will discover that other aspects will fit as well. If we made a mistake, we need to apply force to maintain it and hammer other pieces into place—and unless we correct that mistake, we will need ever more brutal interventions to artificially stabilize the problems which are mere consequences of the original mistake. Think using nuclear weapons to seal off spilling oil wells drilled in deep waters needed because we used up all the easily accessible high-quality fuels. One mistake begets another.

There is a reason why jigsaw puzzles ‘work': they were created that way. There is also a reason why the dance of natural systems ‘works': coevolution. What happens when we run out of steam to stabilize poor designs (i.e. in an energy crisis)? We, as a society, will be forced to confront our past arrogance and pay close attention to resolving the design mistakes we so far always tried to talk away. That’s something I’d call ‘true progress’.

Actually, it’s quite evident now: many of our ‘problems’ are rather just symptoms of more fundamental problems. But as we do not track these down to the actual root, we keep on expending ever more energy by stacking palliatives on top of one another. Growing corn as a biofuel in a process that both requires a lot of external energy input and keeps on degrading soil fertility is a nice example. Now, if we look closer, we find numerous further, superficially unrelated, problems that should make us ask the question: "Did we assemble this part of the puzzle correctly? Is this approach really such a good idea? What else could we do instead? What other solutions would suggest themselves if we paid attention to the hints given by nature?" But we don’t do that. It’s almost as if we were proud to be thick.

JB: How would designing with flows in mind work?

TF: First, we have to be clear about the boundaries of our domain of influence. Resources will at some point enter our domain of influence and at some point leave it again. This certainly holds for a piece of land on which we would like to implement sustainable food production where one of the most important flows is that of water. But it also holds for a household or village economy, where an important flow through the system is that of purchase power—i.e. money (but in the wider sense). As resources percolate through a system, their utility generally degrades—entropy at work. Water high up in the landscape has more potential uses than water further down. So, we can derive a guiding principle for design: capture resources as early as possible, release them as late as possible, and see that you guide them in such a way that their natural drive to go downhill makes them perform many useful duties in between. Considering water flowing over a piece of land, this would suggest setting up rainwater catchment systems high up in the landscape. This water then can serve many useful purposes: there certainly are agricultural/silvicultural and domestic uses, maybe even aquaculture, potentially small-scale hydropower (say, in the 10-100 watts range), and possibly fire control.

JB: When I was a kid, I used to break lots of things. I guess lots of kids do. But then I started paying attention to why I broke things, and I discovered there were two main reasons. First, I might be distracted: paying attention to one thing while doing another. Second, I might be trying to overcome a problem by force instead of by slowing down and thinking about it. If I was trying to untangle a complicated knot, I might get frustrated and just pull on it… and rip the string.

I think that as a culture we make both these mistakes quite often. It sounds like part of what you’re saying is: "Pay more attention to what’s going on, and when you encounter problems, slow down and think about their origin a bit—don’t just try to bully your way through them."

But the tool of measuring flows is a nice way to organize this thought process. When you first told me about ‘input mismatch problems’ and ‘output mismatch problems’, it came as a real revelation! And I’ve been thinking about them a lot, and I want to keep doing that.

One thing I noticed is that problems tend to come in pairs. When the output of one system doesn’t fit nicely into the input of the next, we see two problems. First, ‘waste’ on the output side. Second, ‘deficiency’ on the input side. Sometimes it’s obvious that these are two aspects of the same problem. But sometimes we fail to see it.

For example, a while ago some ground squirrels chewed a hole in an irrigation pipe in our yard. Of course that’s our punishment for using too much water in a naturally dry environment, but look at the two problems it created. One: big gushers of water shooting out of the hole whenever that irrigation pipe was used, which caused all sort of further problems. Two: not enough water to the plants that system was supposed to be irrigating. Waste on one side, deficiency on the other.

That’s obvious, easy to see, and easy to fix: first plug the hole, then think carefully about why we’re using so much water in the first place. We’d already replaced our lawn with plants that use less water, but maybe we can do better.

But here’s a bigger problem that’s harder to fix. Huge amounts of fertilizer are being used on the cornfields of the midwestern United States. With the agricultural techniques they’re using, there’s a constant deficiency of nitrogen and phosphorus, so it’s supplied artificially. The figures I’ve seen show that about 30% of the energy used in US agriculture goes into making fertilizers. So, it’s been said that we’re ‘eating oil’—though technically, a lot of nitrogen fertilizer is made using natural gas. Anyway: a huge deficiency problem.

On the other hand, where is all this fertilizer going? In the midwestern United States, a lot of it winds up washing down the Mississipi River. And as a result, there are enormous ‘dead zones’ in the Gulf of Mexico. The fertilizer feeds algae, the algae dies and decays, and the decay process takes oxygen out of the water, killing off any life that needs oxygen. These dead zones range from 15 and 18 thousand square kilometers, and they’re in a place that’s one of the prime fishing spots for the US. So: a huge waste problem.

But they’re the same problem!

It reminds me of the old joke about a guy who was trying to button his shirt. "There are two things wrong with this shirt! First, it has an extra button on top. Second, it has an extra buttonhole on bottom!"

TF: Bill Mollison said it in a quite humorous-yet-sarcastic way in this episode of the Global Gardener movie:

• Bill Mollison, Urban permaculture strategies – part 1, YouTube.

While the potential to grow a large amount of calories in cities may be limited, growing fruit and vegetables nevertheless does make sense for multiple reasons. One of them is that many things that previously went into the garbage bin now have a much more appropriate place to go—such as the compost heap. Many urbanites who take up gardening are quite amazed when they realize how much of their household waste actually always ‘wanted’ to end up in a garden.

JB: Indeed. After I bought a compost bin, the amount of trash I threw out dropped dramatically. And instead of feeling vaguely guilty as I threw orange peels into the trash where they’d be mummified in a plastic bag in a landfill, I could feel vaguely virtuous as I watched them gradually turn into soil. It doesn’t take as long as you might think. And it comes as a bit of a revelation at first: "Oh, so that’s how we get soil."

TF: Perhaps the biggest problem I see with a mostly non-gardening society is that people without even the slightest own experience in growing food are expected to make up their mind about very important food-related questions and contribute to the democratic decision making process. Again, I must emphasize that whoever does not consciously invest some effort into getting at least some minimal first hand experience to improve their judgment capabilities will be easy prey for rat-catchers. And by and large, society is not aware of how badly they are lied to when it comes to food.

But back to flows. Every few years or so, I stumble upon a jaw-dropping idea, or a principle, that makes me realize that it is so general and powerful that, really, the limits of what it can be used for are the limits of my imagination and creativity. I recently had such a revelation with the PSLQ integer relation algorithm. Using flows as a mental tool for analysis and design was another such case. All of a sudden, a lot made sense, and could be analyzed with ease.

There always is, of course, the ‘man with a hammer problem’—if you are very fond of a new and shiny hammer, everything will look like a nail. I’ve also heard that expressed as ‘an idea is a very dangerous thing if it is the only one you have’.

So, while keeping this in mind, now that we got an idea about flows in nature, let us ask: "how can we abuse these concepts?" Mathematicians prefer the term ‘abstraction’, but it’s fun either way. So, let’s talk about the flow of money in economies. What is money? Essentially, it is just a book-keeping device invented to keep track of favours owed by society to individuals and vice versa. What function does it have? It works as ‘grease’, facilitating trade.

So, suppose you are a mayor of a small village. One of your important objectives is of course prosperity for your villagers. Your village trades with and hence is linked to an external economy, and just as goods and services are exchanged, so is money. So, at some point, purchase power (in the form of money) enters your domain of influence, and at some point, it will leave it again. What you want it to do is to facilitate many different economic activities—so you want to ensure it circulates within the village as long as possible. You should pay some attention to situations where money accumulates—for everything that accumulates without being put to good use is a form of ‘waste’, hence pollution. So, this naturally leads us to two ideas: (a) What incentives can you find to keep money on circulating within the village? (There are many answers, limited only by creativity.) And (b) what can you do to constrain the outflow? If the outlet is made smaller, system outflow will match inflow at a higher internal pressure, hence a higher level of resource availability within the system.

This leads us to an idea no school will ever tell you about—for pretty much the same reason why no state-run school will ever teach how to plan and successfully conduct a revolution. The road to prosperity is to systematically reduce your ‘Need To Earn’—i.e. the best way to spend money is to set up systems that allow you to keep more money in your pocket. An frequent misconception that keeps on arising when I mention this is that some think this idea would be about austerity. Quite to the contrary. You can make as much money as you want—but one thing you should keep in mind is that if you have that trump card up your sleeve that you could at any time just disconnect from most of the economy and get by with almost no money at all for extended periods of time, you are in a far better position to take risks and grasp exceptional opportunities as they arise as someone would be who committed himself to having to earn a couple of thousand pounds a month.

The problem is not with earning a lot of money. The problem is with being forced to continually make a lot of money. We readily manage to identify this as a key problem of drug addicts, but fail to see the same mechanism at work in mainstream society. A key assumption in economic theory is that exchange is voluntary. But how well is that assumption satisfied in practice if such forces are in place?

Now, what would happen if people started to get serious about investing the money they earn to systematically reduce their need to earn money in the future? Some decisions such as getting a photovoltaic array may have ‘payback times’ in the range of one or two decades, but I consider this ‘payback time’ concept as a self-propagating flawed idea. If something gives me an advantage in terms of depending on less external input now, this reduction of vulnerability also has to be taken into account—’payback times’ do not do that. So—if most people did such things, i.e. made strategic decisions to set up systems so that their essential needs can be satisfied with minimal effort—especially money, this would put a lot of political power back into their hands. A number of self-proclaimed ‘leaders’ certainly don’t like the idea of people being in a position to just ignore their orders. Also note that this would have a funny effect on the GDP—ever heard of ‘imputations’?

JB: No, what are those?

TF: It’s a funny thing, perhaps best explained by an example. If you fully own your own house, then you don’t pay rent. But for the purpose of determining the GDP, you are regarded as paying as much rent to yourself (!) as you would get if you rented out the house. See:

Imputed rent, Wikipedia.

Evidently, if people make a dedicated effort at the household level to become less dependent on the economy by being able to provide most of their essential needs themselves (housing, food, water, energy, etc.) to a much larger extent, this amounts to investing money in order to need less money in the future. If many people did this systematically, it would superficially have a devastating effect on the GDP—but it would bring about a much more resilient (because less dependent) society.

The problem is that the GDP really is not an appropriate measure for progress. But obviously, those who publish these figures know that as well, hence the need to fudge the result with imputations. So, a simple conclusion is: whenever there is an opportunity to invest money in a way that makes you less dependent on the economy in the future, that might be well worth a closer look. Especially if you get the idea that, if many people did this, the state would likely have to come up with other imputations to make the impact on the GDP disappear!

JB: That’s a nice thought. I tend to worry about how the GDP and other economic indicators warp our view of what’s right to do. But you’re saying that if people can get up the nerve to do what’s right, regardless, the economic indicators may just take care of themselves.

TF: We have to remember that sustainability is about systems that are viable in the long run. Environmental sustainability is just one important aspect. But you won’t go on for long doing what you do unless it also has economic long-term viability. Hence, we are dealing with multi-dimensional design constraints. And just as flow network analysis is useful to get an idea about the environmental context, the same holds for the economic context. It’s just that the resources are slightly different ones—money, labour, raw materials, etc. These thoughts can be carried much further, but I find it quite worthwhile to instead look at an example where someone did indeed design a successful system along such principles. In the UK, the first example that would come to my mind is Hill Holt Wood, because the founding director, Nigel Lowthrop, did do so many things right. I have high admiration for his work.

JB: When it comes to design of sustainable systems, you also seem to be a big fan of Bill Mollison and some of the ‘permaculture’ movement that he started. Could you say a bit about that? Why is it important?

TF: The primary reason why permaculture matters is that it has demonstrated some stunning successes with important issues such as land rehabilitation.

‘Permaculture’ means a lot of different things to a lot of different people. Curiously, where I grew up, the term is somewhat known, but mostly associated with an Austrian farmer, not Bill Mollison. And I’ve seen some physicists who first had come into contact with it through David Holmgren‘s book revise their opinions when they later read Mollison. Occasionally, some early adopters did not really understand the scientific aspects of it and tried to link it with some strange personal beliefs of the sort Martin Gardner discussed in Fads and Fallacies in the Name of Science. And so on. So, before we discuss permaculture, I have to point out that one might sometimes have to take a close look to evaluate it. A number of things claiming to be ‘permaculture’ actually are not.

When I started—some time ago—to make a systematic effort to get a useful overview over the structure of our massive sustainability-related problems, a key question to me always was: "what should I do?"—and a key conviction was: "someone must have had some good ideas about all this already." This led me to actually not read some well-known "environmentalist" books many people had read which are devoid of any discussion of our options and potential solutions, but to do a lot of detective work instead.

In doing so, I travelled, talked to a number of people, read a lot of books and manuscripts, did a number of my own experiments, cross-checked things against order-of-magnitude guesstimates, against the research literature, and so on. At one point—I think it was when I took a closer look into the work of the laureates of the ‘Right Livelihood award’ (sometimes called the ‘Alternative Nobel Prize’)—I came across Bill Mollison’s work. And it struck a chord.

Back in the 90s, when mad cow disease was a big topic in Europe, I spent quite some time pondering questions such as: "what’s wrong with the way farming works these days?" I immediately recognized a number of insights I independently had arrived at back then when studying Bill Mollison’s work, and yet, he went so much further—talked about a whole universe of issues I still was mostly unaware of at that time. So, an inner voice said to me: "if you take a close look at what that guy already did, that might save you a lot of time". Now, Mollison did get some things wrong, but I still think taking a close look at what he has to say is a very effective way to get a big picture overview over what we can achieve, and what needs urgent attention. I think it greatly helps (at least to me) that he comes from a scientific background. Before he decided to quit academia in 1978 and work full time on developing permaculture, he was a lecturer at the University of Hobart, Tasmania.

JB: But what actually is ‘permaculture’?

TF: That depends a lot on who you ask, but I like to think about permaculture as if it were an animal. The ‘skeleton’ is a framework with cleverly designed ‘static properties’ that holds the ‘flesh’ together in a way so that it can achieve things. The actual ‘flesh’ is provided by solutions to specific problems with long term viability being a key requirement. But it is more than just a mere semi-amorphous collage of solutions, due to its skeleton. The backbone of this animal is a very simple (deliberately so) yet functional (this is important) core ethics which one could regard as being the least common denominator of values considered as essential across pretty much all cultures. This gives it stability. Other bones that make this animal walk and talk are related to key principles. And these principles are mostly just applied common sense.

For example, it is pretty clear that as non-renewable resources keep on becoming more and more scarce, we will have to seriously ponder the question: what can we grow that can replace them? If our design constraints change, so does our engineering—should (for one reason or another) some particular resource such as steel become much more expensive than it is today, we would of course look into the question whether, say, bamboo may be a viable alternative for some applications. And that is not as exotic an idea as it may sound these days.

So, unquestionably, the true solutions to our problems will be a lot about growing things. But growing things in the way that our current-day agriculture mostly does it seems highly suspicious, as this keeps on destroying soil. So, evidently, we will have to think less along the lines of farming and more along the lines of gardening. Also, we must not fool ourselves about a key issue: most people on this planet are poor, hence for an approach to have wide impact, it must be accessible to the poor. Techniques that revolve around gardening often are.

Next, isn’t waiting for the big (hence, capital intensive) ‘technological miracle fix’ conspicuously similar to the concept of a ‘pie in the sky’? If we had any sense, shouldn’t we consider solving today’s problems with today’s solutions?

If one can distinguish between permaculture as it stands and attempts by some people who are interested in it to re-mold it so that it becomes ‘the permaculture part of permaculture plus Anthroposophy/Alchemy/Biodynamics/Dianetics/Emergy/Manifestation/New Age beliefs/whatever’, there is a lot of common sense in permaculture—the sort of ‘a practical gardener’s common sense’. In this framework, there is a place for both modern scientific methods and ancient tribal wisdom. I hence consider it a healthy antidote to both fanatical worship of ‘the almighty goddess of technological progress’—or any sort of fanatical worship for that matter—as well as to funny superstitious beliefs.

There are some things in the permaculture world, however, where I would love to see some change. For example, it would be great if people who know how to get things done paid more attention to closely keeping records of what they do to solve particular problems and to making these widely accessible. Solutions of the ‘it worked great for a friend of a friend’ sort do us a big disservice. Also, there are a number of ideas that easily get represented in overly simplistic form—such as ‘edge is good’—where one better should retain some healthy skepticism.

JB: Well, I’m going to keep on pressing you: what is permaculture… according to you? Can you list some of the key principles?

TF: That question is much easier to answer. The way I see it, permaculture is a design-oriented approach towards systematically reducing the total effort that has to be expended (in particular, in the long run) in order to keep society going and allow people to live satisfying lives. Here, ‘effort’ includes both work that is done by non-renewable resources (in particular fossil fuels), as well as human labour. So, permaculture is not about returning to pre-industrial agricultural drudgery with an extremely low degree of specialization, but rather about combining modern science with traditional wisdom to find low-effort solutions to essential problems. In that sense, it is quite generic and deals with issues ranging from food production to water supply to energy efficient housing and transport solutions.

To give one specific example: Land management practices that reduce the organic matter content of soils and hence soil fertility are bound to increase the effort needed to produce food in the long run and hence considered a step in the wrong direction. So, a permaculture approach would focus on using strategies that manage to build soil fertility while producing food. There are a number of ways to do that, but a key element is a deep understanding of nature’s soil food web and nutrient cycling processes. For example, permaculture pays great attention to ensuring a healthy soil microflora.

When the objective is to minimize the effort needed to sustain us, it is very important to closely observe those situations where we have to expend energy on a continual basis in order to fight natural processes. When this happens, there is a conflict between our views how things ought to look like and a system trying to demonstrate its own evolution. In some situations, we really want it that way and have to pay the corresponding price. But there are others—quite many of them—where we would be well advised to spend some thought on whether we could make our life easier by ‘going with the flow’. If thistles keep on being a nuisance on some piece of land, we might consider trying to fill this ecological niche by growing some closely related species, say some artichoke. If a meadow needs to be mowed regularly so that it does not turn into a shrub thicket, we would instead consider planting some useful shrubs in that place.

Naturally, permaculture design favours perennial plants in climatic regions where the most stable vegetation would be a forest. But it does not have to be this way. There are high-yielding low-effort (in particular: no-till, no-pesticide) ways to grow grains as well, mostly going back to Masanobu Fukuoka. They have gained some popularity in India, where they are known as ‘Rishi Kheti’—’agriculture of the sages’. Here’s a photo gallery containing some fairly recent pictures:

Raju Titus’s Public Gallery, Picasa.

Wheat growing amid fruit trees: no tillage, no pesticides — Hoghangabad, India

An interesting perspective towards weeds which we usually do not take is: the reason this plant could establish itself here is that it’s filling an unfilled ecological niche.

JB: Actually I’ve heard someone say: "If you have weeds, it means you don’t have enough plants".

TF: Right. So, when I take that weed out, I’d be well advised to take note of nature’s lesson and fill that particular niche with an ecological analog that is more useful. Otherwise, it will quite likely come back and need another intervention.

I would consider this "letting systems demonstrate their own evolution while closely watching what they want to tell us and providing some guidance" the most important principle of permaculture.

Another important principle is the ‘user pays‘ principle. A funny idea that comes up disturbingly often up in discussions of sustainability issues (even if it is not articulated explicitly) is that there are only a limited amount of resources which we keep on using up, and once we are done with that, this would be the end of mankind. Actually, that’s not how the world works.

Take an apple tree, for example. It starts out as a tiny seed, and has to accumulate a massive amount of (nutrient) resources to grow into a mature tree. Yet, once it completes its life cycle, dies down and is consumed by fungi, it leaves the world in a more fertile state than before. Fertility tends to keep growing, because natural systems by and large work according to the principle that any agent that takes something from the natural world will return something of equal or even greater ecosystemic value.

Let me come back to an example I briefly mentioned earlier on. At a very coarse level of detail, grazing cows eat grass and return cow dung. Now, in the intestines of the cow, quite a lot of interesting biochemistry has happened that converted nonprotein nitrogen (say, urea) into much more valuable protein:

• W. D. Gallup, Ruminant nutrition, review of utilization of nonprotein nitrogen in the ruminant, Journal of Agricultural and Food Chemistry 4 (1956), 625-627.

A completely different example: nutrient accumulators such as comfrey act as powerful pumps that draw up mineral nutrients from the subsoil, where they would be otherwise inaccessible, and make them available for ecosystemic cycling.

Russian comfrey, Symphytum x uplandicum

It is indeed possible to not only use this concept for garden management, but as a fundamental principle to run a sustainable economy. At the small scale (businesses), its viability has been demonstrated, but unfortunately this aspect of permaculture has not received as much attention yet as it should. Here, the key questions are along the lines of: do you need a washing machine, or is your actual need better matched by the description ‘access to some laundry service’?

Concerning energy and material flows, an important principle is "be aware of the boundaries of your domain of influence, capture them as early as you can, release them as late as you can, and extract as much beneficial use out of them as possible in between". We already talked about that. In the era of cheap labour from fossil fuels, it is often a very good idea to use big earthworking machinery to slightly adjust the topography of the landscape in order to capture and make better use of rainwater. Done right, such water harvesting earthworks can last many hundreds of years, and pay back the effort needed to create them many times over in terms of enhanced biological productivity. If this were implemented on a broad scale, not just by a small percentage of farmers, this could add significantly to flood protection as well. I am fairly confident that we will be doing this a lot in the 21st century, as the climate gets more erratic and we face both more extreme rainfall events (note that saturation water vapour pressure increases by about 7% for every Kelvin of temperature increase) as well as longer droughts. It would be smart to start with this now, rather than when high quality fuels are much more expensive. It would have been even smarter to start with this 20 years ago.

A further important principle is to create stability through a high degree of network connectivity. We’ve also briefly talked about that already. In ecosystem design, this means to ensure that every important ecosystemic function is provided by more than one element (read: species), while every species provides multiple functions to the assembly. So, if something goes wrong with one element, there are other stabilizing forces in place. The mental picture which I like to use here is that of a stellar cluster: If we put a small number of stars next to one another, the system will undergo fairly complicated dynamics and eventually separate: in some three-star encounters, two stars will enter a very close orbit, while the third receives enough energy to go over escape velocity. If we lump together a large number of stars, their dynamics will thermalize and make it much more difficult for an individual star to obtain enough energy to leave the cluster—and keep it for a sufficiently long time to actually do so. Of course, individual stars do ‘boil off’, but the entire system does not fall apart as fast as just a few stars would.

There are various philosophies how to best approach weaving an ecosystemic net, ranging from ‘ecosystem mimicry‘;—i.e. taking wild nature and substituting some species with ecological analogs that are more useful to us—to ‘total synthesis of a species assembly’, i.e. combining species which in theory should grow well together due to their ecological characteristics, even though they might never have done so in nature.

JB: Cool. You’ve given me quite a lot to think about. Finally, could you also leave me with a few good books to read on permaculture?

TF: It depends on what you want to focus on. Concerning a practical hands-on introduction, this is probably the most evolved text:

• Bill Mollison, Introduction to Permaculture, Tagari Publications, Tasmania, 1997.

If you want more theory but are fine with a less refined piece of work, then this is quite useful:

• Bill Mollison, Permaculture – A Designer’s Manual, Tagari Publications, Tasmania, 1988.

Concerning temperate climates—in particular, Europe—this is a well researched piece of work that almost could be used as a college textbook:

• Patrick Whitefield, The Earth Care Manual: a Permaculture Handbook for Britain and Other Temperate Climates, Permanent Publications, East Meon, 2004.

For Europeans, this would probably be my first recommendation.

JB: Thanks! It’s been a very thought-provoking interview.

Ecologists never apply good ecology to their gardens. Architects never understand the transmission of heat in buildings. And physicists live in houses with demented energy systems. It’s curious that we never apply what we know to how we actually live.Bill Mollison

This Week’s Finds (Week 314)

6 June, 2011

This week I’d like to start an interview with Thomas Fischbacher, who teaches at the School of Engineering Sciences at the University of Southampton. He’s a man with many interests, but we’ll mainly talk about sustainable agriculture, leading up to an idea called "permaculture".

JB: Your published work is mainly in theoretical physics, and some of it is quite mathematical. You have a bunch of papers on theories of gravity related to string theory, and another bunch on magnetic materials, maybe with some applications to technology. But you’re also interested in sustainable agricultural and building practices! That seems like quite a leap… but I may be trying to make a similar leap myself, so I find it fascinating. How did you get interested in these other topics, which seem so very different in flavor?

TF: I think it’s quite natural that one’s interests are wider than what one actually publishes about—quite likely, the popularity of your blog which is about all sorts of interesting things witnesses this.

However, if something that seems interesting catches my attention, I often experience a strong drive to come to an advanced level of understanding—at least mastering the key mechanisms. As far as I can think back, my studies have been predominantly self-directed, often following very unusual and sometimes obscure paths, so I sometimes happen to know a few quite odd things. And actually, considering research, I get a lot of fun out of combining advanced ideas from very different fields. Most of my articles are of that type, e.g. "sparse tensor numerics meets database algorithms and metalinguistics", or "Feynman diagrams meet lazy evaluation and continuation coding", or "Exceptional groups meet sensitivity back-propagation". Basically, I like to see myself in the role of a bridge-builder. Very often, powerful ideas that have been developed in one field are completely unknown in another where they actually can be used to great advantage.

Concerning sustainability, it actually was mostly soil physics that initially got me going. When dealing with a highly complex phenomenon such as human civilization, it is sometimes very useful to take a close look at matter and energy flows in order to get an overview over important processes that determine the structure and long term behaviour of a system. Just doing a few order-of-magnitude guesstimates and looking at typical soil erosion and soil formation rates, I found that, from that perspective, quite a number of fundamental things did not add up and told a story very different from the oh-so-glorious picture of human progress. That’s one of the great things about physical reasoning: it allows one to independently make up one’s mind about things where one otherwise would have little other choice than to believe what one is told. And so, I started to look deeper.

JB: So what did you discover? I can’t resist mentioning something I learned from a book Kevin Kelly gave me:

• Neil Roberts, The Holocene: an Environmental History, Blackwell, London, 1998.

It describes how the landscape of Europe has been cycling through glacial and interglacial periods every 100,000 years or so for the last 1.3 million years. It’s a regular sort of pattern!

As a glacial period ends, first comes a phase when birches and pines immigrate from southern refuges into what had been tundra. Then comes a phase when mixed deciduous forest takes over, with oak and elm becoming dominant. During this period, rocky soils turn into brown forest soils. Next, leaching from rocks in glacial deposits leads to a shift from neutral to acid soils, which favor trees like spruce. Then, as spruce take over, fallen needles make the soil even more acid. Together with cooling temperatures as the next glacial approaches, this leads to the replacement of deciduous forest by heathland and pine forests. Finally, glaciers move in and scrape away the soil. And then the cycle repeats!

I thought this was really cool: it’s like seasons, but on a grand scale. And I thought this quote was even cooler:

It was believed by classical authors such as Varro and Seneca that there had once been a "Golden Age", "when man lived on those things which the virgin earth produced spontaneously" and when "the very soil was more fertile and productive." If ever there was such a "Golden Age" then surely it was in the early Holocene, when soils were still unweathered and uneroded, and when Mesolithic people lived off the fruits of the land without the physical toil of grinding labour.

Still unweathered and uneroded! So it takes an ice age to reset the clock and bring soils back to an optimum state?

But your discovery was probably about the effects of humans…

TF: There are a number of different processes, all of them important, that are associated with very different time scales. A general issue here is that, as a society, we have difficulties to get an idea how our life experience is shaped by our cultural heritage, by our species’ history, and by events that happened tens of thousands of years ago.

Coming to the cycles of glaciation, you are right that these shaped the soils in places such as Europe, by grinding down rock and exposing freshly weathered material. But it is also interesting to look at places where this has not happened—to give us sort of an outside perspective; glaciation was fairly minimal in Australia, for example. Also, the main other player, volcanism did not have much of an effect in exposing fresh minerals there either. And so, Australian soils are extremely old—millions of years, tens of millions of years even, and very poor in mineral nutrients, as so much has been leached out. This has profound influences on the vegetation, but also on fauna, and of course on the people who inhabited this land for tens of thousands of years, and their culture: the Aborigines. Now, I don’t want to claim that the Aborigines actually managed to evolve a fully "sustainable" system of land management—but it should be pretty self-evident that they must have developed some fairly interesting biological knowledge over such a long time.

Talking about long time scales and the long distant past, it sometimes takes a genius to spot something that in hindsight is obvious but no one noticed because the unusual situation is that the really important thing that matters is missing. Have you ever wondered, for example, what animal might eat an avocado and disperse its fairly large seed? Like other fruit (botanically speaking, the avocado is a berry, as is the banana), the avocado plant co-evolved with animals that would eat its fruits—but there is no animal around that would do so. Basically, the reason is that we are looking at a broken ecosystem: the co-evolutionary partners of the avocado, such as gomphotheres, became extinct some thousands of years ago.

A blink with respect to the time scales of evolution, but an awfully long time for human civilizations. There is an interesting book on this subject:

• Connie Barlow, The Ghosts of Evolution: Nonsensical Fruit, Missing Partners, and Other Ecological Anachronisms, Basic Books, New York, 2002. (Also listen to this song.)

Considering soils, the cycle of glaciations already should hold an important lesson for us. It is important to note that the plow is basically an invention that (somewhat) suits European agriculture and its geologically young soils. What happens if we take this way of farming to the tropics? While lush and abundant rainforests may seem to suggest otherwise, we have old and nutrient-poor soils here, and most mineral nutrients get stored and cycled by the vegetation. If we clear this, we release a flush of nutrients, but as the annual crops which we normally grow are not that good at holding on to these nutrients, we rapidly destroy the fertility of the land.

There are alternative options for how to produce food in such a situation, but before we look into this, it might be useful to know a few important ballpark figures related to agriculture—plow agriculture in particular.

The most widely used agricultural unit for "mass per area" is "metric tons per hectare", but I will instead use kilograms per square meter (as some people may find that easier to relate to), 1 kilogram per square meter being 10 tons/ha. Depending on the climate (windspeeds, severity of summer rains, etc.), plow agriculture will typically lead to soil loss rates due to erosion of something in the ballpark of 0.5 to 5 kilograms per square meter per year. In the US, erosion rates in the past have been as high as 4 kilograms per square meter per year and beyond, but have come down markedly. Still, soil loss rates of around 1 kilogram per square meter per year are not uncommon for the US. The problem is that, under good conditions, soil creation rates are in the ballpark of 0.02 to 0.2 kilograms per square meter per year. So, our present agriculture is destroying soil much faster than new soil gets formed. And, quite insidiously, erosion will always carry away the most fertile top layer of soil first.

It is worthwhile to compare this with agricultural yields: in Europe, good wheat yields are in the range of 0.6 kilograms per square meter per year, but yields depend a lot on water availability, and the world average is just 0.3 kilograms per square meter per year. In any case, the plow actually produces much more eroded land than food. You can see more information here:

• Food and Agriculture Organization of the UN, FAOSTAT.

Concerning ancient reports of a "Golden Age"—I am not so sure about this anymore. By and large, civilizations mostly seem to have had quite a negative long term impact on the soil fertility that sustained them—and a number of them failed due to that. But all things considered, we often find that some particular groups of species have a very positive long term effect on fertility and counteract nutrient leaching—tropical forests bear witness to that.

Now… what single species we can think of would be best equipped to make a positive contribution towards long-term fertility building?

JB: Hey, no fair—I thought I was the one asking the questions!

Hmm, I don’t know. Maybe some sort of rhizobium? You know, those bacteria that associate themselves to the roots of plants like clover, alfalfa and beans, and take nitrogen from the air and convert it to a form that’s usable by the plants?

But you said "one single species", so this answer is probably not right: there are lots of species of rhizobia.

TF: The answer is quite astounding—and it lies at the heart of understanding sustainability. The species that could have the largest positive impact on soil fertility is Homo sapiens—us! Now, considering the enormous ecological damage that has been done by that single species, such a proposition may seem quite outrageous. But note that I asked about the potential to make a positive contribution, not actual behaviour as observed so far.

JB: Oh! I should have guessed that. Darn!

TF: When I bring up this point, many people think that I might have some specific technique in mind, a "miracle cure", or "silver bullet" idea such as, say, biochar—which seems to be pretty en vogue now—or genetically engineered miracle plants, or some such thing.

But no—this is about a much more fundamental issue. Nature eventually will heal ecological wounds—but quite often, she is not in a particular hurry. Left to her own devices, she may take thousands of years to rebuild soils and turn devastated land back into fertile ecosystems. Now, this is where we enter the scene. With our outstanding intellectual power we can read landscapes, think about key flows—flows of energy, water, minerals, and living things through a site—and if necessary, provide a little bit of guidance to help nature take the next step. This way, we can often speed up the regeneration clock a hundredfold or more!

Let me give some specific examples. Technologically, these are often embarrassingly simple—yet at the same time highly sophisticated, in the sense that they address issues that are obvious only once one has developed an eye for them.

The first one is imprinting—in arid regions, this can be a mind-blowingly simple yet quite effective technology to kick-start a biological succession pathway.

JB: What’s "imprinting"?

TF: One could say, earthworks for rainwater harvesting, but on the centimeter scale. Basically, it is a simple way to implement a passive resource-concentration system for water and organic matter that "nucleates" the transition back from desert to prairie—kind of like providing ice microcrystals in supercooled water. The Imprinting Foundation has a good website. In particular, take a look at this:

• The Imprinting Foundation, Success Stories.

This video is also well worth watching—part of the "Global Gardener" series:

• Bill Mollison, Dryland permaculture strategies—part 3, YouTube.

Here is another example—getting the restoration of rainforest going in the tropical grasslands of Colombia.

• Zero Emissions Research and Initiatives (ZERI), Reforestation.

Here, the challenge is that the soil originally was so acidic (around pH 4) that aluminium went into the soil solution as toxic Al3+. What eventually managed to do the trick was to plant a nurse crop of Caribbean pines, Pinus caribbea (on 80 square kilometers—no mean feat) that have been provided with the right mycorrhizal symbiont (Pisolithus tinctorius, I think) that enabled the trees to grow in very acidic soil. An amazing subject in themselves, fungi, by the way.

These were big projects—but similar ideas work on pretty much any scale. Friends of mine have shown me great pictures of the progress of a degraded site in Nepal where they did something very simple a number of years ago—puting up four poles with strings between them on which birds like to gather. And personally, since I started to seriously ponder the issue of soil compaction and started to give double-digging a try in my own garden a few years ago, the results have been so amazing that I wonder why anyone bothers to garden with annuals any other way.

JB: What’s "double-digging"?

TF: A method to relieve soil compaction. As we humans live our lives above the soil, processes below can be rather alien to us—yet, this is where many very important things go on. By and large, most people do not realize how deep plant roots go—and how badly they are affected by compaction.

The term "double-digging" refers to digging out the top foot of topsoil from the bed, and then using a gardening fork to also loosen the next foot of soil (often subsoil) before putting back the topsoil. Now, this method does have its drawbacks, and also, it is not the "silver bullet" single miracle recipe for high gardening yields some armchair gardeners who have read Jeavons’s book believe it to be. But if your garden soil is badly compacted, as it often is the case when starting a new garden, double-digging may be a very good idea.

JB: Interesting!

TF: So, there is no doubt that our species can vastly accelerate natural healing processes. Indeed, we can link our lives with natural processes in a way that satisfies our needs while we benefit the whole species assembly around us—but there are some very non-obvious aspects to this. Hacking a hole into the forest to live "in harmony with nature" most certainly won’t do the trick.

The importance of the key insight—we have the capacity to act as the most powerful repair species around—cannot be overstated. There is at present a very powerful mental block that shows up in many discussions of sustainability: looking at our past conduct, it is easy to get the idea that Homo sapiens‘ modus operandi is to seek out the most valuable/powerful/convenient resource first, use this up, and then, driven by need, find ways to make do with the next most valuable resource, calling this "progress"—actually a downward spiral. I’ve indeed seen adverts for the emerging Liquefied Natural Gas industry that glorified this as "a motor of progress and growth". Now, the only reason why we consider this is that the more easily-accessible, easy-to-handle fuels have been pretty much used up. Same with deep-sea oil drilling. What kind of "progress" is it that the major difference between the recent oil spill in the Gulf of Mexico and the Ixtoc oil spill in 1979 is that this time, there’s a mile of water sitting on top of the well—because we used up the more easily accessible oil?

• Rachel Maddow, Ixtoc Deepwater Horizon parallels, YouTube.

Now, there are two dominant attitudes toward this observation that we despoil one resource after another.

One is some form of "denial". This is quite widespread amongst professional economists. Ultimately, the absurdity of their argument becomes clear when it is condensed to "sustainability is just one problem among many, and we are the better at solving problems the stronger our economy—so we need to use up resources fast to get rich fast so that we can afford to address the problems caused by us using up resources fast." Reminds me of a painter who lived in the village I grew up in. He was known to work very swiftly, and when asked why he always was in such a hurry, wittily replied: "but I have to get the job done before I run out of paint!"

The other attitude is some sort of self-hate that regards the key problem not as an issue of very poor management, but inherently linked to human existence. According to that line of thinking, collapse is inevitable and we should just make sure we do not gobble up resources so fast that we leave nothing for our children to despoil so that they can have a chance to live.

It is clear that as long as there is a deadlock between these two attitudes, we will not make much progress towards a noticeably more sustainable society. And waiting just exacerbates the problem. So, the key question is: does it really have to be like this—are we doomed to live by destroying the resources which we depend on? Well—every cow can do better than that. Cow-dung is more valuable in terms of fertility than what the cow has eaten. So, if we are such an amazing species—as we like to claim by calling ourselves "Homo sapiens"—why should we fail so miserably here?

JB: I can see all sorts of economic, political and cultural reasons why we do so badly. But it might be a bit less depressing to talk about how we can do better. For example, you mentioned paying attention to flows through systems.

TF: The important thing about flows is that they are a great concept tool to get some first useful ideas about those processes that really matter for the behaviour of complex systems—both for the purpose of analysis as well as design.

That’s quite an exciting subject, but as you mentioned it, I’d first like to briefly address the issue of depressing topics that frequently arise when taking a deeper look into sustainability—in particular, the present situation. Why? Because I think that our capacity as a society to deal with such emotions will be decisive for how well we will do or how badly we will fail when addressing a set of convergent challenges. On the one hand, it is very important to understand that such emotions are an essential part of human experience. On the other hand, they can have a serious negative impact on our judgment capacity. So, an important part of the sustainability challenge is to build the capacity to act and make sound decisions under emotional stress. That sounds quite obvious, but my impression is that, still, most people either are not yet fully aware of this point, or do not see what this idea might mean in practice.

JB: I’ve been trying to build that capacity myself. I don’t think mathematics or theoretical physics were very good at preparing me. Indeed, I suspect that many people in these fields enjoy not only the feeling of "certainty" they can provide, but also the calming sense that the universe is beautiful and perfect. When it comes to environmental issues there’s a lot more uncertainty, and also frequently the sense that the world is messed up—thanks to us! On top of that there’s a sense of urgency, and frustration. All this can be rather stressful. However, there are ways to deal with that, and I’m busy learning them.

TF: I think there is one particularly important lesson I have learned about the role of emotions, especially fear. Important because it probably is quite a fundamental part of the human condition. Emotions do have the power to veto some conclusions from ever surfacing in one’s conscious mind if they would be painful to bear. They can temporarily suspend sound reasoning and also access to otherwise sound memory.

This is extremely sinister, for you are not acting rationally at all, you are in fact driven by one of the most non-rational aspects of your existence, your fear, yet you yourself have next to no chance of ever discovering this, as your emotions abuse your cognitive abilities to systematically shield you from getting conscious access to any insight which would stand a chance of making you question your analysis.

JB: I think we can all name other people who suffer from this problem. But of course the challenge is to see it in ourselves, while it’s happening.

TF: Insidiously, having exceptional reasoning abilities will not help the very least bit here—a person with a powerful mind may be misguided as easily as anybody else by deep inner fears, it’s just that the mind of a person with strong reasoning skills will work harder and spin more sophisticated tales than that of an intellectually average person. So, this essentially is a question of "how fast a runner do you have to be to out-run your own shadow?" How intelligent do you have to be to recognize it when your emotions cause your mind to abuse your powerful reasoning abilities to deceive itself? Well, the answer probably is that the capacity to appreciate in oneself the problem of self-deception is not related to intelligence, but wisdom. I really admire the insight that "it’s hard to fight an enemy who has outposts in your head."

JB: Richard Feynman put it another way: "The first principle is that you must not fool yourself—and you are the easiest person to fool." And if you’re sure you’re not fooling yourself, then you definitely are.

TF: Of course, everything that has an impact on our ability to conduct a sound self-assessment of our own behaviour matters a lot for sustainability related issues.

But enough about the role of the human mind in all this. This certainly is a fascinating and important subject, but at the end of the day, there is a lot of ecosystem rehabilitation to be done, and mapping flows is a powerful approach to getting an idea about what is broken and how to repair it.

JB: Okay, great. But I think our readers need a break. Next time we’ll pick up where we left off, and talk about flows.

Permaculture is a philosophy of working with, rather than
against nature; of protracted and thoughtful observation rather than protracted and thoughtless labour; and of looking at plants and animals in all their functions, rather than treating any area as a single-product system.
– Bill Mollison

The Stockholm Memorandum

1 June, 2011

In May this year, the 3rd Nobel Laureate Symposium produced a document called The Stockholm Memorandum signed by 17 Nobel laureates, presumably from among these participants. It’s a clear call to action, so I’ll reproduce it all here.

I. Mind-shift for a Great Transformation

The Earth system is complex. There are many aspects that we do not yet understand. Nevertheless, we are the first generation with the insight of the new global risks facing humanity.

We face the evidence that our progress as the dominant species has come at a very high price. Unsustainable patterns of production, consumption, and population growth are challenging the resilience of the planet to support human activity. At the same time, inequalities between and within societies remain high, leaving behind billions with unmet basic human needs and disproportionate vulnerability to global environmental change.

This situation concerns us deeply. As members of the 3rd Nobel Laureate Symposium we call upon all leaders of the 21st century to exercise a collective responsibility of planetary stewardship. This means laying the foundation for a sustainable and equitable global civilization in which the entire Earth community is secure and prosperous.

Science indicates that we are transgressing planetary boundaries that have kept civilization safe for the past 10,000 years. Evidence is growing that human pressures are starting to overwhelm the Earth’s buffering capacity.

Humans are now the most significant driver of global change, propelling the planet into a new geological epoch, the Anthropocene. We can no longer exclude the possibility that our collective actions will trigger tipping points, risking abrupt and irreversible consequences for human communities and ecological systems.

We cannot continue on our current path. The time for procrastination is over. We cannot afford the luxury of denial. We must respond rationally, equipped with scientific evidence.

Our predicament can only be redressed by reconnecting human development and global sustainability, moving away from the false dichotomy that places them in opposition.

In an interconnected and constrained world, in which we have a symbiotic relationship with the planet, environmental sustainability is a precondition for poverty eradication, economic development, and social justice.

Our call is for fundamental transformation and innovation in all spheres and at all scales in order to stop and reverse global environmental change and move toward fair and lasting prosperity for present and future generations.

II. Priorities for Coherent Global Action

We recommend a dual track approach:

a) emergency solutions now, that begin to stop and reverse negative environmental trends and redress inequalities in the inadequate institutional frameworks within which we operate, and

b) long term structural solutions that gradually change values, institutions and policy frameworks. We need to support our ability to innovate, adapt, and learn.

1. Reaching a more equitable world

Unequal distribution of the benefits of economic development are at the root of poverty. Despite efforts to address poverty, more than a third of the world’s population still live on less than $2 per day. This needs our immediate attention. Environment and development must go hand in hand. We need to:

• Achieve the Millennium Development Goals, in the spirit of the Millennium Declaration, recognising that global sustainability is a precondition of success.

• Adopt a global contract between industrialized and developing countries to scale up investment in approaches that integrate poverty reduction, climate stabilization, and ecosystem stewardship.

2. Managing the climate – energy challenge

We urge governments to agree on global emission reductions guided by science and embedded in ethics and justice. At the same time, the energy needs of the three billion people who lack access to reliable sources of energy need to be fulfilled. Global efforts need to:

• Keep global warming below 2°C, implying a peak in global CO2 emissions no later than 2015 and recognise that even a warming of 2°C carries a very high risk of serious impacts and the need for major adaptation efforts.

• Put a sufficiently high price on carbon and deliver the G-20 commitment to phase out fossil fuel subsidies, using these funds to contribute to the several hundred billion US dollars per year needed to scale up investments in renewable energy.

3. Creating an efficiency revolution

We must transform the way we use energy and materials. In practice this means massive efforts to enhance energy efficiency and resource productivity, avoiding unintended secondary consequences. The “throw away concept” must give way to systematic efforts to develop circular material flows. We must:

• Introduce strict resource efficiency standards to enable a decoupling of economic growth from resource use.

• Develop new business models, based on radically improved energy and material efficiency.

4. Ensuring affordable food for all

Current food production systems are often unsustainable, inefficient and wasteful, and increasingly threatened by dwindling oil and phosphorus resources, financial speculation, and climate impacts. This is already causing widespread hunger and malnutrition today. We can no longer afford the massive loss of biodiversity and reduction in carbon sinks when ecosystems are converted into cropland. We need to:

• Foster a new agricultural revolution where more food is produced in a sustainable way on current agricultural land and within safe boundaries of water resources.

• Fund appropriate sustainable agricultural technology to deliver significant yield increases on small farms in developing countries.

5. Moving beyond green growth

There are compelling reasons to rethink the conventional model of economic development. Tinkering with the economic system that generated the global crises is not enough. Markets and entrepreneurship will be prime drivers of decision making and economic change, but must be complemented by policy frameworks that promote a new industrial metabolism and resource use. We should:

• Take account of natural capital, ecosystem services and social aspects of progress in all economic decisions and poverty reduction strategies. This requires the development of new welfare indicators that address the shortcomings of GDP as an indicator of growth.

• Reset economic incentives so that innovation is driven by wider societal interests and reaches the large proportion of the global population that is currently not benefitting from these innovations.

6. Reducing human pressures

Consumerism, inefficient resource use and inappropriate technologies are the primary drivers of humanity’s growing impact on the planet. However, population growth also needs attention. We must:

• Raise public awareness about the impacts of unsustainable consumption and shift away from the prevailing culture of consumerism to sustainability.

• Greatly increase access to reproductive health services, education and credit, aiming at empowering women all over the world. Such measures are important in their own right but will also reduce birth rates.

7. Strengthening earth system governance

The multilateral system must be reformed to cope with the defining challenges of our time, namely transforming humanity’s relationship with the planet and rebuilding trust between people and nations. Global governance must be strengthened to respect planetary boundaries and to support regional, national and local approaches. We should:

• Develop and strengthen institutions that can integrate the climate, biodiversity and development agendas.

• Explore new institutions that help to address the legitimate interests of future generations.

8. Enacting a new contract between science and society

Filling gaps in our knowledge and deepening our understanding is necessary to find solutions to the challenges of the Anthropocene, and calls for major investments in science. A dialogue with decision-makers and the general public is also an important part of a new contract between science and society. We need to:

• Launch a major initiative on the earth system research for global sustainability, at a scale similar to those devoted to areas such as space, defence and health, to tap all sources of ingenuity across disciplines and across the globe.

• Scale up our education efforts to increase scientific literacy especially among the young.

We are the first generation facing the evidence of global change. It therefore falls upon us to change our relationship with the planet, in order to tip the scales towards a sustainable world for future generations.

Time to Wake Up?

1 May, 2011

Read this:

• Jeremy Grantham, Time to wake up: days of abundant resources and falling prices are over forever, The Oil Drum, 29 April 2011. Original in PDF.

Jeremy Grantham is the chief investment officer of GMO Capital, a big investment firm. His essay is so readable that there’s no point in trying to outdo it. I’ll just include his summary, which you won’t find on The Oil Drum.

Also, this graph is worth staring at (click to expand):

Many claim that human ingenuity will always keep the price of resources dropping. That was true from 1900 to 2002, with average price decline of 1.2% per year in constant dollars. There were upward spikes for world wars… but the inflationary oil shock of the 1970s was something new: I remember the puzzled, upset mood in the US. But since 2002, according to Grantham, we’ve started seeing something even bigger.

If he’s right, this is very important. What do you think?

Personally I agree completely with his general point that exponential growth is always unsustainable in the long term. Even a civilization expanding through the universe at nearly the speed of light will only grow in a roughly cubic way. Exponential growth is ‘transient behavior’ that happens only near the beginning of a process. So to me, the really interesting question is the empirical one of whether we’re seeing, right now, the transition to a world where resources continue to become more expensive. If you think otherwise, you should convince us that this is a temporary glitch that will end when… something happens.

Summary of the Summary

The world is using up its natural resources at an alarming rate, and this has caused a permanent shift in their value. We all need to adjust our behavior to this new environment. It would help if we did it quickly.


• Until about 1800, our species had no safety margin and lived, like other animals, up to the limit of the food supply, ebbing and flowing in population.

• From about 1800 on the use of hydrocarbons allowed for an explosion in energy use, in food supply, and, through the creation of surpluses, a dramatic increase in wealth and scientific progress.

• Since 1800, the population has surged from 800 million to 7 billion, on its way to an estimated 8 billion, at minimum.

• The rise in population, the ten-fold increase in wealth in developed countries, and the current explosive growth in developing countries have eaten rapidly into our finite resources of hydrocarbons and metals, fertilizer, available land, and water.

• Now, despite a massive increase in fertilizer use, the growth in crop yields per acre has declined from 3.5% in the 1960s to 1.2% today. There is little productive new land to bring on and, as people get richer, they eat more grain-intensive meat. Because the population continues to grow at over 1%, there is little safety margin.

• The problems of compounding growth in the face of finite resources are not easily understood by optimistic, short-term-oriented, and relatively innumerate humans (especially the political variety).

• The fact is that no compound growth is sustainable. If we maintain our desperate focus on growth, we will run out of everything and crash. We must substitute qualitative growth for quantitative growth.

• But Mrs. Market is helping, and right now she is sending us the Mother of all price signals. The prices of all important commodities except oil declined for 100 years until 2002, by an average of 70%. From 2002 until now, this entire decline was erased by a bigger price surge than occurred during World War II.

• Statistically, most commodities are now so far away from their former downward trend that it makes it very probable that the old trend has changed — that there is in fact a Paradigm Shift — perhaps the most important economic event since the Industrial Revolution.

• Climate change is associated with weather instability, but the last year was exceptionally bad. Near term it will surely get less bad.

• Excellent long-term investment opportunities in resources and resource efficiency are compromised by the high chance of an improvement in weather next year and by the possibility that China may stumble.

• From now on, price pressure and shortages of resources will be a permanent feature of our lives. This will increasingly slow down the growth rate of the developed and developing world and put a severe burden on poor countries.

• We all need to develop serious resource plans, particularly energy policies. There is little time to waste.

Mathematics of Planet Earth

20 March, 2011

While struggling to prepare my talk on “what mathematicians can do”, I remembered this website pointed out by Tom Leinster:

Mathematics of Planet Earth 2013.

The idea is to get lots of mathematicians involved in programs on these topics:

• Weather, climate, and environment
• Health, human and social services
• Planetary resources
• Population dynamics, ecology and genomics of species
• Energy utilization and efficiency
• Connecting the planet together
• Geophysical processes
• Global economics, safety and stability

There are already a lot of partner societies (including the American Mathematical Society) and partner institutes. I would love to see more details, but this website seems directed mainly at getting more organizations involved, rather than saying what any of them are going to do.

There is a call for proposals, but it’s a bit sketchy. It says:

A call to join is sent to the planet.

which makes me want to ask “From where?”

(That must be why I’m sitting here blogging instead of heading an institute somewhere. I never fully grew up.)

I guess the details will eventually become clearer. Does anyone know some activities that have been planned?

Mathematical Economics

8 January, 2011

My student Miguel Carrión Álvarez got his Ph.D. in 2004. This is when I was still working on loop quantum gravity. So, he decided to work on a rigorous loop quantization of the electromagnetic field. I like his thesis a lot:

• Miguel Carrión Álvarez, Loop Quantization versus Fock Quantization of p-Form Electromagnetism on Static Spacetimes.

However, he decided to leave mathematical physics when he got his degree… and he switched to finance.

There’s a lot of math in common between quantum field theory and mathematical finance. When you take quantum fluctuations in quantum fields, and replace time by imaginary time, you get random fluctuations in the stock market!

Or at least in some models of the stock market. One difference between quantum field theory and mathematical finance is that the former is famous for predicting certain quantities with many decimal digits of accuracy, while the latter is famous for predicting certain quantities with no digits of accuracy at all! I’m talking about the recent financial crisis.

Miguel and I share an interest in the failures of neoclassical economics. My interest comes from the hope — quite possibly a futile hope — that correcting some mistakes in economic theory could help show us a way out of some problems civilization now finds itself in. In fact, the Azimuth Project has its origins in my old economics diary.

Right now we’re having a little conversation about mathematical economics. Maybe you’d like to join in!

Miguel wrote:

I’ll be teaching parts of two courses on mathematical finance and financial risk management in an ‘Mathematical Engineering’ MSc course at the Universidad Complutense here in Madrid.

I replied:

Cool! Has the way people teach these subjects changed any since the economic crisis? I would hope so…

Miguel replied:

I don’t think it has.

First of all, these courses are mostly technical, as part of a Master’s programme intended to teach people what people do in practice. I don’t think criticizing the foundations is part of the program.

But you may have noticed (for instance, if you follow Krugman in the NYT) that the economic establishment has been very resistant to recognizing that the crisis is an empirical refutation of neoclassical economics. This crisis doesn’t fit within the conceptual framework of NCE, but that’s not a problem as they can just call it an “external shock” and continue pretending that the economy will trend to equilibrium from its new perturbed position. Related jokes of mine include that the recession part of the economic cycle is considered an outlier.

And this is not to speak of mathematical finance, where the situation is even worse. Academics still think that the best way to manage a new risk is to quantify it, define an index, and then create derivatives markets to trade it. In other words, turn all risk into market price risk and then push it all to the least solvent participants on the periphery of the financial system.

I think there is good progress being made by non-mainstream economists. Notably Steve Keen – see here:

• ARGeezer, Steve Keen’s dynamic model of the economy, European Tribune, 23 September 2009.

One of the problems with economics that Steve Keen complains about is that economists generally don’t know much about dynamical systems. I doubt they know what the Lotka-Volterra equation is, let alone understanding it (if you discretize it, the predator-prey model displays chaos like the logistic equation). I also doubt economists know about chaos in the logistic equation:

even if they know about logistic growth models which may not be generally the case either. Their model of the economy seems to be basically the Clausius-Clapeyron equation.

I believe the proper way to look at macroeconomics is as a flow network and as such ideas from category theory may be useful at least to organize one’s thinking.

The economy is a network whose nodes are “agents” and links are “economic relations”. Economic relations are flows, of goods and services in one direction and of money in the other direction (opposite categories via arrow reversal?).

Each node also has a balance sheet: assets and liabilities, and it’s the liabilities that are the key here, because they are mostly monetary. But they are also intertemporal. When you buy on credit, you get a physical asset today in exchange for the promise of cash at a later date. Presumably, the discounted present value of that future cash covers the value of the asset today, and that’s what you book as an asset or a liability. But the asset/liability accrues interest over time so its value changes on the balance sheet, and every so often you still need to make an actual transfer of cash along the an edge of the network. And when IOUs become tradeable (you issue me a bearer-IOU which I can then give to someone else who trusts your credit) they become money, too. And the relative variations in the prices of all these different kinds of money, their liquidity, etc, are key in understanding a recession like the one we’re in, or the growth (ehm, bubble) phase of a business cycle.

I don’t have a theory of this, but I keep thinking in these terms and one thing that seems to come out of it is a sort of “fluctuation-dissipation” relation between market fluctuations in prices and trade volumes, the creation of money-as-debt, and inflation. Because nodes abhor insolvency, fluctuations in cash flows lead to the creation of IOUs, which inflate the money mass. With the analogy inflation ~ dissipation, you get a sense that the more intense the market-induced cash flow fluctuations, the higher the inflation rate of the money mass, through the creation of money-as-tradeable-credit.

But none of this is mainstream economics, though there is an active community around “modern monetary theory”, “chartalism” or “monetary circuit theory” working on similar ideas.

But “Dynamic Stochastic General Equilibrium” is not going to cut it.

Anyway, maybe I could do a guest post on your blog about these things… It’s all very inchoate as you can see.

I also think the parallels between these economic flow networks and ecosystems and climates as matter/energy flow networks are important and such dynamical systems are a relatively unexplored area of mathematical physics – it’s just too difficult to say anything general about them!


Miguel allowed me to post this exchange, noting that he could fill in gaps or moderate excessive claims in the comments. It would be nice if together we could all figure out how to take his thoughts and make them a bit more precise.

In week309 I plan to give an explanation of the Lotka-Volterra equation, based on work Graham Jones has done here:

Quantitative ecology, Azimuth Project.

I’m also dying to talk about flow networks in ecology, so it’s nice to hear that Miguel has been thinking about them in economics.

But here’s a basic question: in what sense do economists model the economy using the Clausius-Clapeyron equation? Is the idea that we can take this equation and use it to model economic equilibrium, somehow? How, exactly?


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