Sunday, November 14, 2010

Sustainability: Part II

A commenter on my previous post informs me that:
The generally accepted definition comes from the Brundtland Report, which defines sustainable development as: "development that meets the needs of the present without compromising the ability of future generations to meet their own needs".
There are two problems with this definition. The first is that implementing it requires us to predict what the future will be like in order to know what the needs of future generations will be. Consider two examples:

1. The cost of solar power has been falling steeply. If that fall continues, in another couple of decades fossil fuels will no longer be needed for most of their current purposes, since solar will be a less expensive alternative. If so, sustainability does not require us to conserve fossil fuels.

2. A central worry of environmentalists for at least the past sixty years or so has been population increase. If that is going to be the chief threat to the needs of future generations then sustainability requires us to keep population growth down, as many have argued.

A current worry in developed countries is population collapse, birth rates in many of them being now well below replacement. With the economic development of large parts of the third world, that problem might well spread to them. If so, sustainability requires us to keep population growth up, to protect future generations from the dangers of population collapse and the associated aging of their populations.

It's easy enough to think of other examples. Generalizing the point, "sustainability" becomes an argument against whatever policies one disapproves of, in favor of whatever policies one approves of, and adds nothing beyond a rhetorical club with which partisans can beat on those who disagree with them.

There is a second and related problem with the definition: whether it is to be defined by individual effects or net effects. If a particular policy makes potable water less available to future generations, with the result that many of them get drinking water in bottles rather than from the tap, but also makes future generations enough richer to more than pay the cost of that bottled water, is that policy consistent with sustainability?

Or consider the issue of global warming. Assume that it can be slowed or prevented, but at the cost of slowing the development of much of the world. To make the point more precise, suppose that global warming imposes an average cost on future generations of 10 utiles (or whatever unit you prefer to use to measure the ability of future generations to meet their own needs), but the policies that prevent it impose a cost of 20. Is permitting global warming sustainable? Is preventing it?

If we define sustainability in terms of individual effects, treating as unsustainable anything which makes future generations less able to meet any one of their needs, there may be no policies at all that are sustainable, since each alternative alters the future in different ways and any alteration is likely to be bad in at least one respect. If, more plausibly, we define it in terms of net effects, then the demand for sustainability turns into the demand that we not follow policies that make future generations worse off than the present generation.

What policies make future generations better or worse off is one of the things people who argue about policy disagree about. It was obvious to a large number of intelligent and thoughtful people early in the past century that socialism made people better off; it is obvious to most such people now that it had the opposite effect. Similarly with current arguments over almost anything, from gay marriage to genetically engineered crops. "Sustainability" becomes an argument for both sides, each interpreting it by its view of the consequences of the policies it supports or opposes.

Not only does the requirement of sustainability add nothing useful to the conversation, it takes something away. It implies that the one essential requirement is making sure our descendants are as well off as we are; whether they end up better off than we are, as we are better off than our ancestors, is relatively unimportant. That surely impoverishes any serious discussion of policies that affect future generations.

I am grateful to the commenter for providing me with a definition, but it does not alter my conclusion. To regard sustainability as a useful and important goal is indefensible.


Miko said...

The problems you propose suggest ways in which the goal may hypothetically be difficult to achieve. They say nothing about whether achieving the goal is desirable.

Simon Dickinson said...

I'm not convinced that the first problem you point out is in fact a problem with sustainability, more a problem with the process of planning. Yes, the idea of sustainability requires - to some degree - an assumption about future requirements. But surely this is right and necessary in the course of any plan? As I see it, it's prudent of businesses and individuals to try to plan for the future, in order to assist them in decisions they make in the present. It is correct to point out that these assumptions may not turn out to be true, but that doesn't stop them from being necessary. By your logic, we'd never make a decision to develop something until we know it's needed. That method is flawed as it is too reactionary; it would cause there to be a period where a need exists, but is not being met.

Consider the example of potable water supply. In Britain (where I live), it's a fair assumption that demand is going to continue to increase in certain parts of the country (namely the South East), and that if this happens the water industry will face big problems to meet the demand. The result would be water shortages, which are clearly not desirable. As a result, there is a great interest from the regulators as well as within the water industry, to try to consider ways to solve this problem. This effort is being done now to solve the problem before it arises; to make the supply "sustainable". If that assumption isn't made - if we say "well we don't know what future demand will be, so we can't plan anything" - then the alternative is to do something when we know that we need to do something; in this instance to react when water shortages start to become even more common. This is not an acceptable course of action, given the importance of a resource such as potable water.

By the way, you are spot on with your example of energy; it may well be that it's sustainable in the short-medium term to continue to use fossil fuels. To be honest I'm not sure what you are trying to illustrate by pointing this out.

I'm only half sure that I understand the second part of your argument, but I largely sympathise with it. There are many advocates of sustainability who are deeply conservative; who are blind to different ways of doing things or the idea that those different methods could be better. To use your first example of drinking water, then we work for now on the assumption that the current method of distribution will continue to be used. But if we discover at some point that it's more efficient to distribute water in bottles, then of course that policy is sustainable. The global warming example is perhaps more interesting. If we discovered that the price of stopping global warming was higher than the damage it would cause (and frankly I would be surprised if this were the case, but I don't think it's by any means inconceivable), then clearly it would not be sustainble to stop it.

I think that your implication is that sustainability is incompatible with growth, and as I see it that just isn't the case. In fact I see it more as trying to maintain growth.

Is sustainability a useful concept? I would say yes. But then my background is in engineering, where I suppose sustainability means providing something which can continue to be useful in future, and will continue to work efficiently (and therefore cheaply). In that regard it's essentially common sense, and I would really be surprised if anyone is against its employment in this respect (as I assume people want cheaper water, electricity, buildings, etc)! I reject the idea that sustainability takes something away from the conversation, and so I disagree that it's an indefensible concept, at least not in every instance.

David Friedman said...

"If we discovered that the price of stopping global warming was higher than the damage it would cause (and frankly I would be surprised if this were the case, but I don't think it's by any means inconceivable), then clearly it would not be sustainable to stop it."

Then what does "sustainable" add to "desirable?" Arguments against doing things that cost more than they are worth are nothing new, and don't require the use of a new term.

"I reject the idea that sustainability takes something away from the conversation"

You recognize that our predictions of the future are uncertain. Hence we will be faced with decisions that involve tradeoffs among objectives. Are we willing to risk doing worse by one measure as the cost of a chance of doing better by another?

Judged by "sustainability," we should never buy a chance of making things better at any risk, however small, of making them worse, which seems unreasonable.

If you treat sustainability as merely one value among many, what does it add? Why should we talk about how to do things in a sustainable way rather than a good way, or a way that, in some average sense, results in a better future?

William B Swift said...

>there may be no policies at all that are sustainable

That's what they want, or haven't you noticed that the people whining about "sustainability" are mostly the same nutjobs promoting the "precautionary principle".

Middle Man said...

Care to rethink your ill considered statement Dr. Friedman:

And that's the anatomical tip of the iceberg of the costs we've lumped onto future generations for the sake of what I don't know. To paraphrase Eugene O'Neil, what was it we wanted to buy, I wonder?

albatross said...

ISTM that there is a whole cluster of related ideas and beliefs and emotional connections and identity surrounding terms like "sustainability" or "diversity" or "free markets." For example, I think there is value to many kinds of diversity (for example, it's cool to have coworkers from many different countries and backgrounds, and good ethnic restaurants all around make for lots of interesting and tasty meals). But if I start talking about "diversity" in a work setting, everyone expects a kind of droning secular sermon on how We Must Embrace Our Differences And Overcome Our Prejudices.

In the same way, when you describe sustainability as the principle that we ought not to dump the costs of our actions onto our grandkids, to the extent we can figure out how to avoid doing so, I find it hard to argue against that. (We are, however, handicapped in our deep ignorance of what our grandkids will think of what we leave them.) But when I hear "sustainability" in a political or administrative context, I expect a kind of secular sermon on how We Must All Love and Respect the Earth.

August said...

It looks to me like a convenient excuse as to why centralized planning has consistently worse outcomes. No, no, it isn't the fatal conceit- our outcomes will just be worse than a freer system because we care, we are trying to be sustainable. They are committed the central planner role, but they've ditched the industrialist socialist utopia rhetoric.

It's blatantly obvious when you come up against situations where the obvious enemy is big government (e.g. slow food movement versus Big Agriculture funded by massive subsidies) and yet they vote for Obama rather than becoming anarchists. When it matters, they stick with the central planning agenda rather than kicking the punks out so we can get some real food.

Xerographica said...

The other day I was eating Sun Chips from the very first biodegradable chip bag while watching the Hope on Wheels Hyundai commercial. Afterwards, I washed my hands with soap from a bottle of Dawn that promised $1/bottle for wildlife.

When Rand Paul drew criticism for opposing government legislation that forces private businesses to follow civil rights laws...his response should have been to redirect attention to consumers.

It's all about ethical consumerism. Well, not entirely...but it does help shift some responsibility from government to consumers.

That being said, I'm not entirely opposed to some soft paternalism.

montestruc said...

I disagree with one aspect of your argument. While it is reasonable to state that in the future solar and other forms of energy will probably be cheaper that fossil fuels, as fossil fuels also have great utility in other applications (chemical feedstock in manufacture of a huge number of synthetic materials, and medications, and lubricants for example) their is a legitimate reason to conserve petroleum in the ground. Thing is oil companies already do that, so the market has an answer for that.

Maik said...

David: If, more plausibly, we define it in terms of net effects, then the demand for sustainability turns into the demand that we not follow policies that make future generations worse off than the present generation.

I agree. But "sustainability" is a nice buzz word for that, and given that humans are not naturally apt to plan beyond their own life span, a may be nice to have buzz word that reminds them of the need from time to time.

David: It implies that the one essential requirement is making sure our descendants are as well off as we are; whether they end up better off than we are, as we are better off than our ancestors, is relatively unimportant.

I did not read that into the definition, but maybe that's due to my limited knowledge of English. Perhaps a less ambiguous term than "compromising" (either "impairing" or "risking") would be better in the definition.

Terramar GM said...

David: It looks to me like there are two meanings of "sustainability" (so I agree with what albatross said, and go further).

One is the sensible version, which means something like "Internalize all costs" and/or and "Don't do anything that has a negative net present value." As far as I can tell this is perfectly compatible with libertarianism; it's like the Lockean Proviso.

The other meaning is, basically, "Don't cause a net decrease in finite resources." This is wrong for the reasons you point out, and possibly others as well.

@Middle Man What part/s/ of David's statement do you consider incorrect? Or, if you think everything in it is correct, can you explain why you think it's ill-considered?

I'm assuming you think that David means "We should not pay any attention to pollution, depletion of finite resources, climate change, or any other effects our actions have on the environment."

I agree with you that such a position is wrong; so does David.

Libertarians believe that pollution, depletion of resources, and other environmental damage to anyone's property is a violation of the owner's property rights; and even our strongest opponents admit that we're fanatical about defending people's property rights.

jimbino said...

Many of us who are childfree have already chosen not to invest in future generations. Why the hell should we not use up our share of air, water and oil right now and let those who have an interest in future generations conserve their own share of resources without taxing us?

The last thing I want is to maintain the world safe for spoiled Amerikan kids of helicopter parents.

Andrew said...

Jimbino's point is exactly why we need sustainability. There are strong actors with morally legitimate positions that say "let's use up all of our resources before I'm dead". To balance out those people politically we need extremists who overvalue the future.

Dorje Mundle said...

You make some good, valid points but take such a narrow view that critically undermine your argument.

I agree there are definitional challenges with SD, which mean that people can twist & interpret to suit their own agenda. This is especially true when you stick with the brundtland definition at a generalised level. But drill down to specific issues / geographies and it gets much more manageable (cf the other commenter's example of sustainable water consumption in England).

Your point that as we don't know what will happen in the future hence the notion of SD is useless, is frankly nonesense! We predict and plan for the future in all disciplines all the time, and have to make use of the best available info, methodologies and minds to do so, and then periodically revise as new info becomes available. No different with SD.

"If we discovered that the price of stopping global warming was higher than the damage it would cause (and frankly I would be surprised if this were the case, but I don't think it's by any means inconceivable), then clearly it would not be sustainable to stop it."

You miss the whole issue of equity here. If it's more expensive for 1 billion high income consumers to abate their high per capita emissions, but the economic impact is felt disproportionately by the 5 billion low income consumers who live in more agriculturally dominated markets, with less government spending power to adapt to the adverse effects of climate change, is it still the right thing to just view this as a macro-economic decision? Ask farmers facing accelerated desertification, or pacific islanders who are losing their homelands, and they would disagree...

Anonymous said...

Might you not want to revise your initial definition? It is 30 years old. About as up to date as your thinking on this.

California Trip 2010/11 said...

Sustainability can be defined as dV/dt >0 (= lamdba * dk/dt) , where V is the value function from an expanded Ramsey problem (it includes all relevant stocks and flows). This boils down to monitoring the portfolio of welfare relevant stocks. It certainly allows us to extract non-renewables etc, because it is the sum of dk/dt that matters. Alternatively, one can use a change of wealth measure, as we did here: .

David Socrates said...

David: You ask ...what does "sustainable" add to "desirable?"

Exactly. Precisely. You have expressed the problem in a nutshell.

All the examples in this blog trail are simply human issues that need honest and vigorous debate. This is simply the way open societies advance. Using a new word for normal discourse between human beings adds absolutely nothing.

The best example of this superfluity of concept is in the global warming debate. There is now an increasingly fierce controversy about whether man-made CO2 emissions are making ANY significant effect on the environment. Just suppose for a moment that the skeptics turn out to be right on this. Our best sustainability option would then clearly be to do nothing at all to limit carbon emissions. Ha!

Grant McDermott said...

Rather late to the party here, but your post(s) remind me of an old fable about peat farming:

Two centuries ago, a farmer in Ireland calculated how much peat he and his family needed to subsist. He marked fields for a maximum number of generations that could subsist from the peat on his land and made a vow not to take more than his share. So did his son, and grandson. But one day there was no more peat dug up, and there was plenty left.

Of course, there are no guarantees that every generation will happen upon fossil fuels, or the whatever the relevant equivalent is. (The farmer's position would have been far more reasonable had he lived several centuries earlier...) See Jared Diamond's book, Collapse, for some insight into what happens when societies fail to utilise their resources "sustainably".

And, yes, unfortunately the standard definitions of sustainability are almost unbearably amorphous. Would it be too much to paraphrase Potter Steward's famous aphorism on pornography?... "We may not be able to define sustainability, but we know it when we see it."

Eric Rasmusen said...

Someone commented:
If, more plausibly, we define it in terms of net effects, then the demand for sustainability turns into the demand that we not follow policies that make future generations worse off than the present generation.

That's how I read the definition at the top of the post. It's the only way to make sense of it. And in that case, sustainability is a very easy goal to meet, requiring no modification whatsoever in any current policies, at least economically. It would require heroically bad policies to have longterm negative GDP per capita growth in the face of technological advances. Probably even the anti-growth policies of the global warmists couldn't do it. One could argue that such things as crime and moral collapse have resulted in reductions in happiness, but that's going beyond what the Sustainability people are thinking about.