Again, Malthus was right (in the past)

By Razib Khan | March 30, 2010 1:15 am

Ed reviews a new paper on the fall of the Angkor civilization. He concludes:

Of course, a changing environment was far from the only reason behind the fall of Angkor. By the time the droughts kicked in, the city was already weakened by social, economic and political strife. Buckley simply thinks that the climate simply sealed the city’s demise. In fact, others have suggested that some force may have pushed the local people to move from inland agriculture to maritime trade. Buckley says that this transition coincides neatly with the aftermath of the first drought.

An economic historian might term the droughts which Angkor was subjected to an “exogenous shock.” Basically an outside factor which slams into an equilibrium system periodically (I assume that super-droughts would exhibit a poisson distribution but readers more climatically savvy can correct me). On the other hand, there are parameters which are endogenous to the system; consider the institutional frameworks which regulate social relations and distribute economic surplus.

Pre-modern societies often live on the Malthusian margin on a per capita basis. In other words, the average Chinese peasant was no more wealthy than the barbarian nomad to the north (in fact, a peasant may be less wealthy on a median basis than a nomad for a variety of reasons). Despite the greater sum total of wealth of pre-modern China, and so the greater surplus which the rentier elites could tax or steal, most of that wealth vis-a-vis Mongolia or Central Asia was realized in the form of people. That wealth was fundamentally based on primary production, agriculture, and when the environmental conditions for agriculture were less favorable then the wealth would decrease. Naturally you would then see a major contraction in the primary manifestation of that wealth, census size. If that environment once more became favorable toward primary production then there might be a transient where individual per capita wealth increased before census size “caught up” (e.g., the average English peasant in the century after the Black Death was healthier and wealthier than before because the population was so much smaller).

Grand per-modern polities such the the Khmer confederacy of which Angkor was the apex rely on massive numbers of primary producers from which they can skim and squeeze just short of destitution. In other words the elites who produced high culture were parasites. Civilization was located for most of history in cities, and all cities before 1900 were demographic sinks due to the pervasiveness of morbidity and mortality. Environmental catastrophe which forces the primary producers to look to themselves and evade or dodge taxation or theft by the elites results in the collapse of civilization. This environmentally induced collapse was not limited to the Khmer confederacy in Southeast Asia, in Strange Parallels: Volume 1, Integration on the Mainland: Southeast Asia in Global Context, c. 800-1830 the author shows that the same dynamic of disruption and destabilization was evident to the west and east, from Myanmar to Vietnam, correlated with climatic variation in the region.

But things are never always the same. Similar environmental catastrophes did not result in total dissolution of the political order after 1500 in mainland Southeast Asia, the institutional framework which generated some sort of equilibrium managed to withstand exogenous shocks because they had become more robust. The same is evident on a global scale in The Human Web: A Bird’s-Eye View of World History and After Tamerlane: The Global History of Empire Since 1405; political institutions over the past 2,500 years are much more robust than they were in the first 2,500 years of civilization. And they have been much more robust over the past 500 years than the previous 2,000 years. There are long term institutional changes which occurred through which we must view the predicted impact of environmental catastrophe. I am not here even touching upon the rapid rise in economic growth which allowed much of humanity to break out of the Malthusian trap after 1850 (see A Farewell to Alms).

The main caution from history would be supplied by Brian Fagan in The Long Summer: How Climate Changed Civilization. He admits that political institutions during the Holocene have become more robust, dampening the impact of local famines or disruptions. But, he observes that when collapse does happen it is all the more catastrophic as enormous interlocking social, political and technological systems may now unwind. In other words, we’re trading short term small risks for longer term large risks. The analogy that seems appropriate here is that of earthquakes, whereby small quakes tend to release energy which might otherwise pour out in a super-quake. This is why I like to suggest that only technology will save us.

CATEGORIZED UNDER: Anthroplogy, Economics, History
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  • moptop

    It is amazing that the left can point to Malthus over and over again in the past, but when presented with the modern Malthusian Vortex of a govt that hands out manna unsustainably, and which is headed towards what sure looks like inevitable collapse, Greece, California, the left can’t see it.

  • Jody

    most of that wealth vis-a-vis Mongolia or Central Asia was realized in the form of people
    Stray thought – when Malthus is right, so is Marx (labor theory of value). When Malthus is wrong, so is Marx.

  • moptop

    I am just curious, and admit that I haven’t read Marx, but does Marx assign any value to intellectual property in his theory of labor?

  • Brian Schmidt

    moptop – IIRC, no, although he understood the importance of technological transformations and believed capitalism to be a huge step above feudalism.

    As for the political lectures to the left, you might also try it on the party that run the US govt from 2001-2009 and took the budget from surplus to a huge deficit just as the Baby Boomers began to drop out of the work force and retire.

  • moptop

    Well, then, the obvious problem with Marxism is that it can’t exploit smart people. I used to listen to a show on NPR called Exquisite Corpse, and the host grew up in Communist Czechoslovakia, as it was called then. He said that all of his educated friends took menial jobs since they paid the same as demanding jobs, and this saved their intellectual energy for their art.

    Gifts are not handed out equally at birth. Smart people can find other ways of occupying their minds than producing ideas that benefit the general welfare, like improved medical technology, or what have you. As long as it doesn’t affect their lifestyle anyway, why not write poetry for their friends?

    As for your other comment. I really think you ought to look at deficits and trends and which parties hold the purse strings (run congress), rather than cherry picking dates of elections of presidents. But that is an endless area of discussion on which we obviously will never agree. I doubt either one of us has any arguments the other hasn’t heard, so let’s just agree not to go there. OK?

  • pconroy


    The Bush administration was fiscally liberal and socially conservative – never mind their party affiliations.

    The Obama administration is fiscally ultra-liberal and socially liberal.

    What I’d prefer would be fiscally conservative and socially liberal.

  • moptop

    Maybe if Marx defined Intellectual Capital as a “work product” of a “primary producer”? Naah! The whole scheme falls apart.

  • miko

    @pconroy: compared to who? those assessments are roughly true in the context of recent U.S. national politics, but span a very, very narrow range of both fiscal and social liberalism/conservativism.

  • Aisha Tushoski

    i dont know how i discovered your blog as a result of i was searching details about politics, but anyway, i had a pleasant time reading it, maintain write it

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About Razib Khan

I have degrees in biology and biochemistry, a passion for genetics, history, and philosophy, and shrimp is my favorite food. In relation to nationality I'm a American Northwesterner, in politics I'm a reactionary, and as for religion I have none (I'm an atheist). If you want to know more, see the links at


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