A Rebuttal of "The Last Bite"

Permit me a brief digression from this blog's usual subject matter to address and attempt to rebut a New Yorker article entitled "The Last Bite," which has been circulating around the food blogosphere (thanks to CheapHealthyGood for being the first site to connect me to the article). This article, a Malthusian polemic on how the world's food system is on the brink of collapse, is well-written and highly persuasive.

Correction: it's extraordinarily persuasive.

Unfortunately, the article is also fatuous, wrong, and worst of all (worst in my opinion anyway), not predictive.

What's both fascinating and intellectually intriguing about Malthusian arguments like this one is that they are almost always cogently argued and seem so logically airtight. The math of Thomas Malthus (or our own modern version of Malthus, Paul Ehrlich) is inescapable. Only a fool would dispute the simple fact that while human populations grow at a compound rate, the food supply can grow only at a linear rate. Still worse, land supply is essentially fixed.

On top of that, "The Last Bite" layers on yet another depressing and seemingly inescapable point: per capita food consumption is increasing, as people in the emerging economies of the world adopt western-style diets.

In short, with its compelling anecdotes and dire conclusions, this article is causing outbreaks of gloom and despair all over blogland.

But what's missing from this article, and why its entire Malthusian thesis is fatally flawed, is that it ignores a critical variable: exogenous innovation.

Let's back up to Malthus himself to look at an illustrative example. Malthus completely omitted the impact that massive improvements in agricultural yields would have on his argument. He left it out because it never occurred to him that a collection of agricultural innovations, developed gradually by farming communities throughout England, could combine into an exogenous force powerful enough to undo his entire thesis.

And lest you think I'm beating up on Malthus too much, keep in mind that nobody else anticipated his era's green revolution either. It just happened. But it is a particularly harsh irony that this green revolution began shortly after the ink dried on his book.

Likewise, later Malthusians failed to incorporate the even more significant agricultural yield improvements of the 19th century, and of course missed yet again the staggering yield improvements seen in the 20th century (see for example the green revolution in India in the 1960s).

"It's tough to make predictions, especially about the future."
--Yogi Berra

Why are dire predictions about the future so often wrong, and quite often so monstrously wrong? In short, because economic systems--and for that matter most systems that involve human beings--are recursive. Meaning, people inside the system see what's going on around them, hear these predictions about the future, and adjust their behavior. If gasoline prices go up a lot, people will drive less. If beef prices go up, people will become part-time vegetarians. This changes the dynamics of the system on the fly, and it makes even the best efforts at prediction fruitless--and often highly embarrassing for those making the predictions.

Take for example a market for rice. A current rice shortage will drive recursive behavior in the very short term that might well exacerbate the shortage, as people may hoard or gouge prices. But other actors in that market will see the higher rice prices, and--with proverbial dollars signs in their eyes--react by producing more rice. A longer term shortage will unlock additional recursive behavior, perhaps by making it increasingly profitable to till land currently used for other purposes, or by making it worthwhile to invent better seeds or better growing techniques.

Innovation and exogenous solutions will always be the biggest and most unpredictable input in any economic system. We're fortunate that we live in a world where there are enormous economic incentives to solve these types of problems. You can get very, very rich if you can bring a meaningfully productive innovation to the marketplace.

The negative, doom-and-gloom arguments always seems so prudent, so logical and so rigorous. And of course it seems fundamentally unrigorous, even naive, to base a view of the future on some hoped-for exogenous innovation that nobody even knows about yet.

But here's the thing: all innovations are by definition unknown and inconceivable, otherwise they'd already be conceived and in use by now!

It may seem unrigorous, but it is actually more accurate and more predictive to trust in innovation to help solve problems like those discussed in "The Last Bite" that today seem so dire and intractable. That's really the way the future works.

Links for further reading:
1) If you're interested in yet another example of how Malthusian thinking misses the mark, this time pertaining to predicting grievous commodity shortages, have a look at Wikipedia's highly balanced retelling of
the famous Ehrlich-Simon bet. It's ironic of course that if these gentlemen had made this bet 10 years ago (instead of in 1980), it would have gone the other way.

2) Wired Magazine's
engaging profile of Julian Simon, the man on the winning side of the Ehrlich-Simon bet.

3) Malthus's famous book:
An Essay on the Principle of Population

4) Looking for more "rigorously" argued reasons to despair? See Paul Ehrlich's
The Population Bomb


Anonymous said...

You know, I have lurked on your site for months now (LOVE it, by the way, have tried out a lot of your recipies and suggestons to almost unvaryingly successful outcomes) and this is the very first time I have felt compelled to post a comment.

It is so refreshing when I come across clear, rational, and - dare I say it - sane thinking when it comes to these "doomsday" topics that are so prevalent. It is a curiosity that the general population seems to have such an aversion to bringing their beliefs, ideas, and ideologies into line with radical things like facts, history, and reality, but that is what seems to happen. I loved the clear and concise way you responded to that inflammatory and completely ridiculous tripe and absolutely appreciated the extra reading material. I hadn't seen that wired profile of Mr Simon before and thoroughly enjoyed reading it. Bravo!

Daniel said...

Thank you for your comment and for your compliments! I really appreciate it.

This is the sort of positive feedback that makes blogging a true pleasure. Thank you.


Anonymous said...

I agree in general, but if "people inside the system see what's going on around them, hear these predictions about the future, and adjust their behavior", aren't these predictions necessary to bring about the recursive behavior which then adjusts the outcome? Wrong, but effective rather than futile?

Plus, they sell books and give people something to blog about! :)

Daniel said...

Ha! Great point!

The Malthusians undo their doomsday predictions by convincing people that the predictions will come true.

Thanks for your comment!


Anonymous said...

I hear what you're saying, but I still think Social Security is doomed.

teflaime said...

perhaps by making it increasingly profitable to till land currently used for other purposes

Unfortunately, the land so cultivated is almost always wild land needed to maintain the health of the planet, as opposed to industrial land that no longer serves a useful industrial purpose.

Daniel said...

I don't know if I agree with your broad brush statement that it's almost always wild land.

Certainly that's a problem in many developing counties (eg: clearing of rainforests), but if you ever fly across Europe or the USA and look down, you can see a preposterous amount of fallow land that could be reallocated for agriculture if there was demand for it.