Paul Krugman on Limits to Growth: Beware the Bathwater

by Brian Czech

BrianCzechCongratulations to Paul Krugman, whose New York Times opinion on “Slow Steaming and the Supposed Limits to Growth” hit the bulls-eye of at least one balloon. Landing at Washington-National the very day his opinion column appeared was like crashing back into the growth fetish of the American Fourth Estate. Out came the fresh air of an Australian balloon; back to the polluted, cynical rhetoric that “there is no conflict between growing the economy and protecting the environment.”

Why the drama with Krugman’s column? Partly due to uncanny timing; partly due to the stark juxtaposition of opinions. Having delivered the keynote address–on limits to growth no less–at the Australian Academy of Science’s annual conference on environmental science, it struck me that decades of careful research could be undermined by the presumptuous pen of a well-placed economist. Something is wrong with that picture.

But only for so long, because those of us who recognize limits to growth have sound science, common sense, and burgeoning evidence on our side. The same cannot be said for Krugman’s opinion.

Krugman got off to a shaky start with the very title of his column. No matter what he could say about “slow steaming,” this was bound to be an article wrong-headed in using one sector (shipping) for drawing broad conclusions about a macroeconomic issue (economic growth). To extend a conclusion from the part to the whole is to commit the fallacy of composition. In this case, it’s a bit like Krugman saying, “Your fingernails keep growing; why not the rest of you too?”

The mistake is common and destructive. When this mistake is made by a highly acclaimed economist in a widely-read opinion, the potential for destruction is multiplied. Politicians hide behind such Pollyannaish opinions to pull out all the stops–fiscal and monetary–for economic growth. The casualties include not only environmental protection but the future economy and ultimately national security.

Next, in Krugman’s lead-in paragraph he laments the “unholy alliance on behalf of the proposition that reducing greenhouse gas emissions is incompatible with growing real GDP.” Already we have two more problems. First, the argument alluded to in the title–that is, refuting limits to growth–is reduced to refuting just one negative impact of growth (that is, climate change). What about all the other impacts and limitations of economic growth: liquidation of natural resources, pollution at large, habitat loss, biodiversity decline, and social side effects such as noise, congestion, and stress?

Second, in a maxed-out, over-stimulated, 90% fossil-fueled economy, Krugman wants us to believe we can grow the economy even more while reducing greenhouse gas emissions. No need to worry about little trends such as tar-sands mining in Canada, coal mining in China, and fracking in the USA. Slower steaming will save the day on climate change, and presumably for the rest of the planetary ecosystem.

Let’s not let Krugman delude us. “Growing real GDP” isn’t about an efficiency gain here and there. It means increasing production and consumption of goods and services in the aggregate. It entails a growing human population and/or per capita consumption. It means growing the whole, integrated economy: agriculture, extraction, manufacturing, services, and infrastructure. From the tailpipe of all this activity comes pollution.

Krugman seems to have fallen for the pixie dust of “dematerializing” and “green growth” in the “Information Economy.” He may want to revisit Chapter 4 of The Wealth of Nations, where Adam Smith pointed out that agricultural surplus is what frees the hands for the division of labor. In Smith’s day that included the likes of candle-making and pin manufacturing. Today it includes everything from auto-making to information processing, but the fundamentals haven’t changed. No agricultural surplus, no economic growth. And agriculture is hardly a low-energy sector.

Adam Smith was among the great, classical economists who readily recognized limits to growth, all the way until at least John Stuart Mill. After that and throughout the 20th century, things got murky for economists as they turned increasingly to microeconomics, losing the forest for the trees. Mr. Krugman appears to be yet another victim of the “neoclassical” evolution of economics. Look to him for insightful opinions on banking regulations, fiscal politics, and other such topics that fit naturally under the rubric of an economics columnist. These are his babies, but beware the bathwater. Take his opinion on limits to growth at your peril, and that of your grandkids.

Krugman’s Growthism

by Herman Daly

Herman Daly


Paul Krugman often writes sensibly and cogently about economic policy. But like many economists, he can become incoherent on the subject of growth. Consider his New York Times piece, published earlier this month:


…let’s talk for a minute about the overall relationship between economic growth and the environment.

Other things equal, more G.D.P. tends to mean more pollution. What transformed China into the world’s largest emitter of greenhouse gases? Explosive economic growth. But other things don’t have to be equal. There’s no necessary one-to-one relationship between growth and pollution.

People on both the left and the right often fail to understand this point…On the left, you sometimes find environmentalists asserting that to save the planet we must give up on the idea of an ever-growing economy; on the right, you often find assertions that any attempt to limit pollution will have devastating impacts on growth…[Krugman says both are wrong]…But there’s no reason we can’t become richer while reducing our impact on the environment [emphasis mine].

Krugman distances himself from “leftist” environmentalists who say we must give up the idea of an ever-growing economy, and is himself apparently unwilling to give it up. But he thinks the “right-wingers” are wrong to believe that protecting the environment will devastate growth. Krugman then advocates the more sensible goal of “becoming richer,” but fails to ask if growth in GDP is any longer really making us richer. He seems to equate, or at least fails to distinguish, “growing GDP” from “becoming richer.” Does he assume that because GDP growth did make us richer in yesterday’s empty world it must still do so in today’s full world? The usual but unjustified assumption of many economists is that a growing GDP increases measured wealth by more than it increases unmeasured “illth” (a word coined by John Ruskin to designate the opposite of wealth).

To elaborate, illth is a joint product with wealth. At the current margin, it is likely that the GDP flow component of “bads” adds to the stock of “illth” faster than the GDP flow of goods adds to the stock of wealth. We fail to measure bads and illth because there is no demand for them, consequently no market and no price, so there is no easy measure of negative value. However, what is unmeasured does not for that reason become unreal. It continues to exist, and even grow. Since we do not measure illth, I cannot prove that growth is currently making us poorer, any more than Krugman can prove that it is making us richer. I am just pointing out that his GDP growthism assumes a proposition that, while true in the past, is very doubtful today in the US.

To see why it is doubtful, just consider a catalog of negative joint products whose value should be measured under the rubric of illth: climate change from excess carbon in the atmosphere; radioactive wastes and risks of nuclear power plants; biodiversity loss; depleted mines; deforestation; eroded topsoil; dry wells, rivers and aquifers; the dead zone in the Gulf of Mexico; gyres of plastic trash in the oceans; the ozone hole; exhausting and dangerous labor; and the un-repayable debt from trying to push growth in the symbolic financial sector beyond what is possible in the real sector (not to mention military expenditures to maintain access to global resources).

Deforestation–one of the many “illths” created by continual GDP growth

These negative joint products of GDP growth go far beyond Krugman’s minimal nondescript category of “pollution.” Not only are these public bads un-subtracted, but the private anti-bads they make necessary are added to GDP! For example, the bad of eroded topsoil is not subtracted, but the anti-bad of fertilizer is added. The bad of Gulf and Arctic oil spills is not subtracted, but the anti-bad of clean-up is added. The natural capital depletion of mines, wells, forests, and fisheries is falsely accounted as income rather than capital draw-down.

Such asymmetric accounting alone is sufficient to refute growthism, but for good measure note that the growthists also neglect the most basic laws of economics, namely, the diminishing marginal benefit of income and increasing marginal cost of production. Why do they think these two curves will never intersect? Is Krugman just advocating temporary growth up to some level of optimality or sufficiency, or an ever-growing economy? If the latter, then either the surface of the Earth must grow at a rate approximating the rate of interest, or real GDP must become “angel GDP” with no physical dimension.

Krugman is correct that that there is no necessary “one-to-one relationship between growth and pollution.” But there certainly is a very strong positive correlation between real GDP growth and resource throughput (the entropic physical flow that begins with depletion and ends with pollution). Since when do economists dismiss significant correlations just because they are not “one-to-one”?

Probably we could indeed become richer (increase net wealth) while reducing our impact on the environment, as Krugman hopes. But it will be by reducing uneconomic growth (in throughput and its close correlate, GDP) rather than by increasing it. I would be glad if this were what Krugman has in mind, but I doubt that it is.

In any case, it would be good if he would specify whether he thinks current growth in real GDP is still economic in the literal sense that its benefits exceed its costs at the margin. What specifically makes him think this is so? In other words, is GDP growth currently making us richer or poorer, and how do we know?

Since GDP is a conflation of both costly and beneficial activity, should we not separate the cost and benefit items into separate accounts and compare them at the margin, instead of adding them together? How do we know that growth in GDP is a sensible goal if we do not know if the associated benefits are growing more or less rapidly than the associated costs? Mainstream economists, including Krugman, need to free their thinking from dogmatic GDP growthism.

Growth and Free Trade: Brain-Dead Dogmas Still Kicking Hard

by Herman Daly

Herman DalyThere are two dogmas that neoclassical economists must never publicly doubt lest they be defrocked by their professional priesthood: first, that growth in GDP is always good and is the solution to most problems; second, that free international trade is mutually beneficial thanks to the growth-promoting principle of comparative advantage. These two cracked pillars “support” nearly all the policy advice given by mainstream economists to governments.

Even such a clear thinker as Paul Krugman never allows his usually admirable New York Times column to question these most sacred of all tenets. And yet in less than 1,000 words the two dogmas can easily be shown to be wrong by just looking at observable facts and the first principles of classical economics. Pause, and calmly consider the following:

(1) Growth in all micro-economic units (firms and households) is subject to the “when to stop rule” of optimization, namely stop when rising marginal cost equals declining marginal benefit. Why does this not also apply to growth of the matter-energy throughput that sustains the macro-economy, the aggregate of all firms and households? And since real GDP is the best statistical index we have of aggregate throughput, why does it not roughly hold for growth in GDP? It must be because economists see the economy as the whole system, growing into the void — not as a subsystem of the finite and non-growing ecosphere from which the economy draws resources (depletion) and to which it returns wastes (pollution). When the economy grows in terms of throughput, or real GDP, it gets bigger relative to the ecosystem and displaces ever more vital ecosystem functions. Why do economists assume that it can never be too big, that such aggregate growth can never at the margin result in more illth than wealth? Perhaps illth is invisible because it has no market price. Yet, as a joint product of wealth, illth is everywhere: nuclear wastes, the dead zone in the Gulf of Mexico, gyres of plastic trash in the oceans, the ozone hole, biodiversity loss, climate change from excess carbon in the atmosphere, depleted mines, eroded topsoil, dry wells, exhausting and dangerous labor, exploding debt, etc. Economists claim that the solution to poverty is more growth — without ever asking if growth still makes us richer, as it did back when the world was empty, or if it has begun to make us poorer in a world that is now too full of us and our stuff. This is a threatening question, because if growth has become uneconomic then the solution to poverty becomes sharing now, not growth in the future. Sharing is now called “class warfare.”

(2) Countries whose growth has pushed their ecological footprint beyond their geographic boundaries into the ecosystems of other countries are urged by mainline economists to continue to do so under the flag of free trade and specialization according to comparative advantage. Let the rest of the world export resources to us, and we will pay with exports of capital, patented technology, copyrighted entertainment, and financial services. Comparative advantage guarantees that we will all be better off (and grow more) if everyone specializes in producing and exporting only what they are relatively better at, and importing everything else. The logic of comparative advantage is impeccable, given its premises. However, one of its premises is that capital, while mobile within nations, does not flow between nations. But in today’s world capital is even more mobile between countries than goods, so it is absolute, not comparative advantage that really governs specialization and trade. Absolute advantage still yields gains from specialization and trade, but they need not be mutual as under comparative advantage — i.e., one country can lose while the other gains. “Free trade” really means “deregulated international commerce” — similar to deregulated finance in justification and effect. Furthermore, specialization, if carried too far, means that trade becomes a necessity. If a country specializes in producing only a few things then it must trade for everything else. Trade is no longer voluntary. If trade is not voluntary then there is no reason to expect it to be mutually beneficial, and another premise of free trade falls. If economists want to keep the world safe for free trade and comparative advantage they must limit capital mobility internationally; if they want to keep international capital mobility they must back away from comparative advantage and free trade. Which do they do? Neither. They seem to believe that if free trade in goods is beneficial, then by extension free trade in capital (and other factors) must be even more beneficial. And if voluntary trade is mutually beneficial, then what is the harm in making it obligatory? How does one argue with people who use the conclusion of an argument to deny the argument’s premises? Their illogic is invincible!

Like people who can’t see certain colors, maybe neoclassical economists are just blind to growth-induced illth and to destruction of national community by global integration via free trade and free capital mobility. But how can an “empirical science” miss two red elephants in the same room? And how can economic theorists, who make a fetish of advanced mathematics, persist in such elementary logical errors?

If there is something wrong with these criticisms then some neoclassical colleague ought to straighten me out. Instead they lamely avoid the issue with attacks on nameless straw men who supposedly advocate poverty and isolationism. Of course rich is better than poor — the question is, does growth any longer make us richer, or have we passed the optimum scale at which it begins to make us poorer? Of course trade is better than isolation and autarky. But deregulated trade and capital mobility lead away from reasonable interdependence among many separate national economies that mutually benefit from voluntary trade, to the stifling specialization of a world economy so tightly integrated by global corporations that trade becomes, “an offer you can’t refuse.”

Will standard economists ever pull the plug on brain-dead dogmas?