Monday, September 23, 2013

What does Sen have to do with Malthus?

A commenter questioned my association of Sen with Malthus the other day in my thinking-out-loud lecture planning, and I thought I'd elaborate a little more.

First, when I present the class with "modern Smithians" or "modern Malthusians" I like cases that don't precisely match up. Why? Because economic science is progressive and for the most part ideas persist but are changed, formalized, evolved, etc. I'm sure I could find people that think Smith or Malthus or Keynes had it EXACTLY right and that we should treat their work like scripture, but those sorts of people aren't very good representatives of economic science (and - tellingly - it's hard to find those sorts of people in the highest ranks of the science). If, instead, you have someone that takes a Smithian or Malthusian idea and then develops it, that gives the class something to talk about and think about in terms of the development of economic thought (which is, after all, what the course is about). I am very explicit about this in class discussions - that these thinkers are not exactly the same.

But there obviously has to be some continuity - so why associate Sen with Malthus? First, both were concerned with what Malthus would call "positive checks" and their impact on the poor, with population, with inequality, and with famine. So just like the endogenous fertility modelers I talked about (Oded Galor), we have a common research agenda.

But I'm not sure a common research agenda alone would be sufficient. The students actually read Malthus, they don't get the sound-bite version of Malthus, and by reading him they learn that he actually did not think that the poor were doomed to die of famine because there just wasn't enough food. Famine is one of the positive checks, but it is treated quite distinctly from the other positive checks. Malthus thinks famine is an unusual case. He notes that unlike positive checks like war or disease, people go through famine as a result of their relative ability to participate in markets. A rich person may very well die of disease (perhaps at a lower rate than the poor), but only the poor will starve to death. Famine can be ameliorated by market exchange in a way that a lot of the other positive checks can't, and therefore it is uniquely governed by the state of income distribution.

This is what we see in Sen, of course. Famines are not cases where not enough food is produced. Instead, famines are cases where not enough food can be purchased - they are a problem of distribution, not production. As a result they principally impact the lower classes.

We also talked about an interesting discussion in Malthus on why this is not widely discussed. Malthus's answer foreshadows two other modern research agendas. First, he says that nobody writes histories of the poor. People only write histories of war, politics, and the wealthy. His principle of population was likely operating for all of human history but people missed it because nobody had any interest in writing histories of the lower classes. This observation foreshadows the "social history" movement of the 1960s (which continues with force today), and of course earlier efforts at that sort of social history by Engels, etc. Malthus also argues that people have ignored the population pressures he discusses because of the difficulty of thinking in terms of real wages (remember - this is the age before price indices were easily downloadable!). He explains why nominal wages are generally downwardly rigid, and since adjustments for real wages are difficult people miss the decline in real wages. This, of course, foreshadows the burgeoning literature on real wage cyclicality in the late twentieth century.

I like this use of "modern Smithians" and "modern Malthusians" in the class. Most of the students are unfamiliar with the people I discuss, so it introduces them to important twentieth century economists. It also gives me an opportunity to make important observations on how science develops over time.

We are getting into Ricardo tomorrow (if Kate doesn't go into labor, that is). I'm probably not going to talk about any modern Ricardians on the first day (when we discuss factor prices), although I'll obviously note the proto-marginalism, or the second day on trade (except to note that this view is dominant aside from the "new trade theory", which we already discussed in the Smith class). But on the third day when we talk about Ricardo on public finance and on machinery I'm going to bring up Robert Barro as a modern Ricardian (for the public finance discussion we're going to be reading portions from his Essay on the Funding System that go over what we now call "Ricardian equivalence").

I'd be interested in hearing thoughts on any other "modern Ricardians" worth discussing in any of these classes as well.


  1. Actually, apart from Gregory Clark, there is another economist I would like to suggest as a "modern Malthusian" (even though this one is no longer among the living): Ester Boserup. Although she is presented as being opposed to Malthusianism, her insights can be synthesized with the Malthusian edifice.

    I would also suggest another economic historian as a "modern Malthusian": E.A. Wrigley. (He has published research that can be seen as support for the arguments of Malthusianism.)

    But have you considered naming Geoffrey Gilbert and John M. Pullen as "modern Malthusians", Daniel Kuehn? (I believe that both men concentrate on T.R. Malthus.)

    1. If we're admitting the somewhat-recently-deceased, with "recently" being interpreted liberally, to the pantheon of modern Malthusians then Michael Postan (and all his students and "allies") is the key guy, though in terms of Economic History he was much more of the History part. To exaggerate a bit, Postan is probably the main reason why actually "traditional" modern historians take Malthus seriously.

      Wrigley (actually Wrigley and Schoefield) are/were very much Malthusians. The whole argument of the Population History of England is that Malthus had it right, as far as England is concerned, with the Preventive Check being given centerpiece in the narrative. Although that had to be revised after some criticism from other historians.

      I would actually count Boserup as a Malthusian even though her whole point was that Thomas was wrong, or at least missing a good chunk of the story. She was Malthusian in the sense that she took him seriously. Interestingly enough there is some "Boserupian" elements in the Essay itself, though they tend to be the parts where Malthus looses the logical consistency of his argument. Early on he describes the adjustment process to the "Malthusian" equilibrium, makes an unconvincing case for population "overshooting" and then talks about how, more or less, putting it into modern terms, once population has increased and laborers have become impoverished, the landlords switch to labor-intensive technologies and the low wages enable them to develop land-augmenting technological improvements. Which sounds similar to Ester's idea of technological innovation spurned by the imisserization of the population. This part is just me making my own HET stuff up though.

  2. When I teach Ricardo, I discuss Sraffa and the modern surplus school (Heinz Kurz most prominently). I see Sraffa as a brilliant rational reconstruction of Ricardo. Ricardo's essay on profits, with his corn/corn model was in fact the source of Sraffa's idea of the Standard Commodity. Sraffa's editing of the Collected Works led directly to his contribution to modern economics - perhaps the most dramatic instance we have of the capacity for the study of HET to inspire and inform contributions to economic science.

  3. So those discussing the same issues are in the same line of thought, even if they differ in their conclusions.

    1. I would argue their theoretical conclusions are quite similar.

      Are you thinking their policy ideas? Those are different, it's true, but we spend a lot more time talking about economics than we do talking about policy or politics.


All anonymous comments will be deleted. Consistent pseudonyms are fine.