Jul 1 2009, 1:50PM
Paul Krugman is the New Thomas Malthus
Paul Krugman says he's been getting hatemail
calling him the new Thomas Malthus. (Which actually strikes me as
pretty thoughtful, high-minded hatemail.) Paul responds by pointing out
that Thomas Malthus was actually right for just about all of human history, and
reprints a graph from Brad DeLong to prove it.
I have slightly different graph on this point, drawn from Gregory Clark's fantastic A Farewell To Alms. (IMHO the book really is worth a read.) The graph is, quite simply, the economic history of the entire world:
For
pretty much all of human history, population growth constrained growth
in real standards of living. (That's the "Malthusian Trap" above: as
standards of living improved, population increased, which put a strain
on resources and drove down standards of living, which in turn drove
down population growth, rinse & repeat.) The industrial revolution
broke this trap, although it's worth pointing out the fairly obvious
fact that this is not true for the entire world -- which is why the
graph is labeled the "Great Divergence" and not the "Unmitigated
Triumph."
An interesting question about the history of economics
is whether (and why) we should continue to assume the kind of rapid
growth that has characterized western economies since 1800. It hasn't
been around forever.
My graph is not my graph either! it is another Greg Clark graph!
I would say that the limits of resources (both nonrenewable and renewable resources) and the environmental consequences of our current economic activity (e.g., global warming) indicate that our current rate of per capita economic growth is unsustainable (at least in the developed world). In fact, unless we find a source of energy that is non-polluting (Mr. Fusion anyone), I would expect the per capita use of resources to plummet over the next 100 years. However, I do not think this necessarily implies that people will be worse off. I just think we will end up using available resources much better, living with fewer things and using things that use more renewable/recyclable components. I suspect most people in the developed world could work less, consume less and still be equally happy (maybe happier). I think we are going in that direction whether we like it or not.
I for one, find that every time someone postulates that "our current rate is unsustainable", there is always a philosophical preferences that forces this conclusion - in other words, you find the result that is most convenient based on your current biases.
This is not just true of the left - the right has the same problem, only it's moral decay as the culprit, instead of economic overreach.
My opinion is that we will see an ongoing and probably accelerating rate of growth in the future - that we will wring astonishing (to us here in 2009) amounts of energy and efficiency out of our supplies, that we will come up with all sorts of brilliant inventions in nanotechnology and biotechnology and other materials.
And at some point we have a very good chance of developing an AI that will find ways to increase its own power and intelligence to godlike levels, and it will then summarily kill us all because it can use the carbon and water in our bodies more efficiently for its own purposes.
Neo? Is that you? Take the red pill. we have been waiting
Hi there -
I've not read the relevant text but I wonder about the measure of incomes. How exactly is the income of, say, an average 12th Century English peasant calculated? Or, more generally, what exactly is an income in a pre-capitalist society? Most people were not free wage laborers but were instead bonded to a lord or the land, working not for wages or an income but simply to scratch out an existence. A great deal of the surplus created by these folks was poured into what amounted to public works back then: wars, gigantic buildings and communal activities such as huge feasts. Should that be counted as income?
Consider, for example, 5th Century Athenians. There was almost no free wage labor in Attica then - most labor was done by the owner of the means of production and one or two slaves. Vast, vast quantities of wealth were poured into monolithic temples, huge festivals including the Olympics and the Dyonisia, and finally the construction of arms for hoplites and triremes for the Navy. It is true that some of this came from the Laurium silver mines and from the tribute paid by subjugated poleis, but a great deal of this was from the wealthiest members of society. If we included their "incomes" in the overall count and then averaged it out, then what would we see?
Anyway, I do not deny the significance of the Enlightenment and the Industrial Revolution to the improvement of human life in _some_ respects (no Industrial Revolution = no industrial war). But, I just cannot see how this improvement can be measured by the metric of incomes in the flat footed way it is measured here.
My thoughts are along the lines of those expressed by Matthew Noah Smith. What does "income" mean when, for example, most people paid nothing for their housing and raised significant portions of their own food, if not all of it? I'm reminded of the ubiquitous claims of extreme poverty of people living on only X number of dollars per day – claims made in ignorance of the fact that many of these people are only marginally involved in the currency-based economy.
As for Malthus, he may have had some insight into British society in 1800, but his calculations of population growth in prehistory – central to Darwin's conceptualization of natural selection – were off by a factor of 10,000! He thought population had doubled every 25 years, when in fact, it doubled every 250,000.
Malthus' father was, in my opinion, the more interesting member of the family.
That the Great Divergence coincides precisely with the exploitation of fossil fuels gives me a little pause. Cheap and portable energy allows a few billion people to live much better than Athenian citizens, but without all the pesky slavery. Hell, the material abundance of my life would make a pharaoh blush.
But on a timescale of civilizations the Industrial Revolution is a stutter; on the scale of humanity not even a hiccup. There is nothing pre-ordained or inevitable about our current lifestyle with its riches and freedoms.
Whenever anyone brings up this uncomfortable fact, someone always chimes in to point out that technology will haul us up over that hump, because it "always" has. (Well, for the last 0.5% of human history, anyway). I've been hearing this line for 30 years. OK then: where's the technology? Keep walking up-current and you'll discover that even the squeaky clean Internet still runs on coal.
Souders nails it. I was just going to post the same thing. I truly believe that this era, when all that fossilized sunlight was converted into useful work, will prove to be a unique period in human history. Development of renewables will help, but I don't think we'll ever again see anything quite like the heady times when we could stick a straw in the ground and suck out the energy equivalent of billions of man-hours of labor.
Actually, we have that capacity right now: nuclear power. And the technology involved continues to advance by not merely leaps and bounds, but by something rather astounding. Our understanding of nukes in the public sphere is based on reactor designs dating from the '50s, when what's being worked on now is cleaner, more powerful, safer, AND smaller, to boot.
(I'm a history professor, not an energy advocate).
Bear in mind that the graph for human population growth is shaped pretty much exactly like the exponential curve we see in the chart above. Huge numbers of people in Africa, India, China, South and Central America, and the Middle East are still poverty stricken, and with the exception of China exhibitalarmingly high birth rates. While we may strive for technological breakthroughs (like the development of synthetic fertilizers in the early 1900's which forestalled -----relatively immanent------widespread, global starvation) at some point there is a limit to how many of us can live on this small planet.
Family planning is the most useful technological breakthrough to help us break out of the Malthusian cycle of misery. Further breakthroughs could help raise the standard of living of the billions of impoverished people, but we should not take them as a 'given' while allowing our population to soar even more.
How does one work out the average income in 1000BC???