<p>This question rests on a few assumptions.</p>
<p>So let's dig into them.</p>
<h1>What Malthus Said</h1>
<p>First, the Malthusian collapse you are referring to is similar to the Malthusian Trap, from whence it derives, so let's look at that.</p>
<p>From <a href="http://en.wikipedia.org/wiki/Malthusian_trap" rel="nofollow noreferrer">Wikipedia</a>:</p>
<blockquote>
<p>In accordance with the theory, cross-country evidence indicates that technological superiority and higher land productivity had significant positive effects on population density but insignificant effects on the standard of living, during the time period 1–1500 AD. In addition, scholars have reported on the lack of a significant trend of wages in various places over the world for very long stretches of time. In Babylonia during the period 1800 to 1600 BC, for example, the daily wage for a common laborer was enough to buy about 15 pounds of wheat. In Classical Athens in about 328 BC, the corresponding wage could buy about 24 pounds of wheat. In England in 1800 AD the wage was about 13 pounds of wheat. In spite of the technological developments across these societies, the daily wage hardly varied. In Britain between 1200 and 1800, only relatively minor fluctuations from the mean (less than a factor of two) in real wages occurred in Britain. They peaked at around 1450 and in 1800 they were actually significantly worse.</p>
</blockquote>
<p>So to go back to the source, Malthus didn't predict a population explosion at all (or food price rises for that matter). In fact, his theory was specifically that population growth fluctuated with economic development such that the prices of wheat (in terms of wages) remained relatively stable over two millennia.</p>
<p>This was known as the Malthusian Trap, where technological advancement would always be matched by (not exceeded by) population growth, resulting in the stagnation of living conditions.</p>
<p>Since the time of Thomas Malthus, new evidence has emerged that, while the trap may exist, many societies break out of it, and achieve explosive growth in living conditions. This is generally termed, the &quot;breakout&quot;. In <i>A Trap At The Escape From The Trap?</i><span class="math-container">$^1$</span>, <a href="http://en.wikipedia.org/wiki/Andrey_Korotayev" rel="nofollow noreferrer">Andrey Korotayev</a> suggests that this breakout leads to social upheaval, and may have played a role in events like the revolutions in Latin America, or possibly even the formation of the US. Unfortunately if we delve too far down the social macroevolution road we wind up having to have the <a href="http://en.wikipedia.org/wiki/Guns,_Germs,_and_Steel" rel="nofollow noreferrer">Guns, Germs, and Steel</a> discussion, and that's straying dangerously off topic, though I also want to throw in a reference to <a href="http://en.wikipedia.org/wiki/Samuel_P._Huntington" rel="nofollow noreferrer">Huntington</a>, as another great and accessible read on the really big picture.</p>
<h1>But More People...!</h1>
<p>But moving back to your assumptions. Let's assume that population and technological growth became uncoupled by the &quot;breakout&quot;. Now all of a sudden standards of living are at all time historical highs. Under Malthus we would expect the population growth rate to also be at historical highs.</p>
<p>But it's not.</p>
<p>In fact much of the developed world is at &quot;peak population&quot;, facing major demographic shifts as baby-boomers age out of the workforce faster than they are being replaced.
Japan faces a &quot;<a href="http://www.economist.com/blogs/banyan/2014/03/japans-demography" rel="nofollow noreferrer">demographic crisis</a>&quot;<a href="http://en.wikipedia.org/wiki/Aging_of_Japan" rel="nofollow noreferrer"><span class="math-container">$^2$</span></a><a href="http://www.wwq.jp/indexfr.html" rel="nofollow noreferrer"><span class="math-container">$^3$</span></a>, the <a href="http://www.census.gov/popclock/" rel="nofollow noreferrer">US shows substantial aging</a> and even <a href="https://www.google.com/publicdata/explore?ds=d5bncppjof8f9_&amp;ctype=l&amp;strail=false&amp;bcs=d&amp;nselm=h&amp;met_y=sp_pop_grow&amp;scale_y=lin&amp;ind_y=false&amp;rdim=region&amp;idim=country:CHN:IND:USA&amp;ifdim=region&amp;tdim=true&amp;hl=en&amp;dl=en&amp;ind=false" rel="nofollow noreferrer">China's growth rate has slowed dramatically and is now lower than the US's</a>.</p>
<p>In fact, according to the UN, the projected world population over the next several decades looks like this:<br>
<img src="https://i.sstatic.net/DcCSF.png" alt="enter image description here" /></p>
<p>Which you may notice is not an explosive growth. For more information on this, I'll defer to the experts at the Population Division of the Department of Economic and Social Affairs, and their <a href="http://www.un.org/en/development/desa/population/publications/technical/2013-3.shtml" rel="nofollow noreferrer">technical paper</a></p>
<h1>Cause and also Cause</h1>
<p>Lastly, you're assertions rely on the assumption that increased population means food prices go up.</p>
<p>But that's not how numbers work.</p>
<p>Prices are denominated in currency.</p>
<p>More people (without a correlating rise in currency), actually means there's fewer dollars per person. In that scenario, food prices would go <strong>down</strong> (although probably slower than wages), leading to shortages. Price is a way of rationing scarce resources, but it's not the only way. The other way to ration is queueing, or shortage. This is what we see happen in developing nations. Rice is not more expensive, there just isn't enough rice there.</p>
<p>If everyone only has \$5 a rice merchant can't charge \$6/lb, or he won't sell any.</p>
<h1>An Inflationary Theory</h1>
<p>In the event that the population increased, <strong>and</strong> central banks also increased money supply, than standard economic models would predict that the prices of all commodities (not just food) would rise, since the relationship to amount of quantity over the amount money would have changed, or roughly</p>
<p><span class="math-container">$$\rho (\Delta P_n, \Delta \frac{M_0}{Q_n})&gt;0$$</span></p>
<p>where <span class="math-container">$\rho$</span> is correlation, and <span class="math-container">$P_n$</span> and <span class="math-container">$Q_n$</span> are price and quantity of <span class="math-container">$n$</span> respectively. Of note, there is some disagreement o whether <span class="math-container">$M_0$</span> or another measure of money should be used, but prices in the US (as measured by CPI) have a substantial correlation with <span class="math-container">$M_0$</span> (<span class="math-container">$\rho = 0.46$</span> for <span class="math-container">$M_0$</span> as compared to <span class="math-container">$0.086$</span> for <span class="math-container">$M_1$</span> from 1985-2013)<span class="math-container">$^3$</span></p>
<p>This would be conformant with standard economics, and not reliant on a Malthusian population collapse.</p>
<p>The only way we would expect prices to rise dramatically without central bank intervention would actually be <strong>after</strong> the collapse, as people accumulated currency, and would trade more currency for food.</p>
<h1>TL;DR</h1>
<p>In the event of a zombie or post-nuclear apocalypse, cash will decline in value relative to commodities, so stock up on rations and bullets because dollars won't help.<span class="math-container">$^4$</span></p>
<h1>References</h1>
<p><span class="math-container">$^1$</span>: Korotayev, A.; et al. (2011). &quot;A Trap At The Escape From The Trap? Demographic-Structural Factors of Political Instability in Modern Africa and West Asia&quot;. Cliodynamics 2/2: 1–28. <br/><br/>
<span class="math-container">$^2$</span>: Aging of Japan. (2014, December 9). Retrieved December 18, 2014, from <a href="http://en.wikipedia.org/wiki/Aging_of_Japan" rel="nofollow noreferrer">http://en.wikipedia.org/wiki/Aging_of_Japan</a> <br /><br/>
<span class="math-container">$^3$</span>: Current research. You'll have to take my word or pull the data from St Louis Fed and BLS yourself.
<br /><br/>
<span class="math-container">$^4$</span>: <i>Fallout: New Vegas</i>. (2010). United States of America: Bethesda Softworks.</p>

CC BY-SA 3.0
2017-08-16T04:29:20.813Z
This is mind boggling. Amazing!!
EconJohn
CC BY-SA 3.0
2014-12-18T19:44:25.820Z
sadly work sometimes interferes with play. :)
Jason Nichols
CC BY-SA 3.0
2014-12-18T17:24:16.573Z
2014-12-20T05:46:08.043Z
2020-06-17T09:40:54.643Z
Jason Nichols
<p>Malthusians and Neo-Malthusians believe that, eventually, the population of the earth will be exceed the number of people able to be sustained by the earth's food production.  As such, they advocated different forms of population control.<br>
However, it appears that an increase in the population beyond that of the food supply would cause an increase in the overall <strong>real</strong> price for food.<br>
Proponents of Malthusianism, evidently, are not waiting for food prices to rise before advocating population control, but I do not see how we should be worried until the <strong>real</strong> price of food increases.<br>
If Malthusianism is correct, how soon before the population crash would prices begin to rise? </p>

CC BY-SA 3.0
2014-12-18T14:44:26.703Z
This question doesn't seem answerable, as no accepted economic theories (that I know of) predict such a timeline. Some would predict the possible causal relationship between increased real food prices and decreased fertility, but economics tends not to deal with delusional demographic sensationalism. The world population is ageing quickly with "peak population" having occurred in much of the developed world, and even China's growth rate slowing. Consequently no model would predict a Malthusian crisis, let alone a timeline for it.
Jason Nichols
CC BY-SA 3.0
2014-12-18T15:42:36.767Z
@JasonNichols I would propose to turn this comment into an answer. Indeed, currently there is a consensus that there is no projected long-term trend for continuously growing population, so the Malthusian argument becomes irrelevant. But I don't see reason to close the question.
Alecos Papadopoulos
CC BY-SA 3.0
2014-12-18T16:21:16.873Z
@AlecosPapadopoulos I didn't vote to close (as a mod I can't vote) I deleted the one-liner non-answer. Ironically, I added mine as a comment because I felt it wasn't up to the standards of a good answer either. :)
Jason Nichols
CC BY-SA 3.0
2014-12-18T16:25:14.097Z
@JasonNichols Ok, If I want to be strict, I would say that indeed, your comment would be a bona fide answer if it included some references/studies to the fact that we do not expect a constant rise in human population over the long-term. In case you have the time to find some such studies, it would be even better.
Alecos Papadopoulos
CC BY-SA 3.0
2014-12-18T16:31:41.543Z
working on one now, mostly just citing the original work by Malthus, since he explicitly did not predict either a catastrophic rise in food prices or population (in fact his prediction was about the gradual stabilisation of food prices to historic norms and the fact that the quality of life hadn't changed for the peasantry in 2100 years or so).
Jason Nichols
CC BY-SA 3.0
2014-12-18T17:34:42.420Z
@JasonNichols as a mod, you *can* vote to close: the difference is that your vote is always decisive. The community can reopen a mod-closed question, so there are checks and balances (whereas the community cannot undelete a mod-deleted question). You've been trusted with mod tools and mod powers, and it is ok to use them: when you know a question should be put on hold, please do it. Having said that, it's also good to let the community find its feet and get used to moderating itself too. Do ask in the Teachers' Lounge if in doubt.
410 gone
CC BY-SA 3.0
2014-12-18T17:37:25.887Z
@EnergyNumbers, that's what I meant by "can't vote". I try to keep a light hand, and let the community sort it out, unless it's really, really egregious, then I'm more apt to just delete. Otherwise I try to comment. I also don't believe all "bad" questions need to be closed, that's why we have downvotes.
Jason Nichols
CC BY-SA 3.0
2014-12-18T17:39:44.230Z
@JasonNichols If a question needs editing before it's a good question (and I think that applies to this question, YMMV), that is **exactly** what closing is for: it puts the question on hold for a week to give the OP and others chance to improve it. Reluctance to close bad questions will lead to them crowding out good question.
410 gone
CC BY-SA 3.0
2014-12-18T19:35:34.227Z
@JasonNichols Any help on improving this question would be appreciated. So far, no one has offered any constructive criticism on the question (though the constructive criticism on the prospective answer has been insightful, to me at least).
Mathematician
CC BY-SA 3.0
2014-12-18T19:35:55.643Z
@AlecosPapadopoulos Any help on improving this question would be appreciated. So far, no one has offered any constructive criticism on the question (though the constructive criticism on the prospective answer has been insightful, to me at least).
Mathematician
CC BY-SA 3.0
2014-12-18T19:36:18.853Z
@EnergyNumbers Any help on improving this question would be appreciated. So far, no one has offered any constructive criticism on the question (though the constructive criticism on the prospective answer has been insightful, to me at least).
Mathematician
CC BY-SA 3.0
2014-12-18T19:43:23.597Z
Again, @Mathematician I didn't vote to close. I think the question is broad, but not close worthy. I think it rests on faulty and self-contradicting premises, but that's addressed in the answer, and I don't know that it could be 'edited' to be less broad. I'd say more specific questions like, "Would an increase in population trigger a substantial rise in food prices?" would be better, and could be answered more accurately allowing for discussion of the relationship between money multipliers, velocity of money, demand and price at much greater depth.
Jason Nichols
CC BY-SA 3.0
2014-12-18T20:28:06.543Z
@Mathematician I don't see a way to salvage it, myself. It's predicated on something that's untrue, and I don't see it as an informative counter-factual either. The Malthusian population growth model turned out to be nonsense, and his model of food growth was no better either.
410 gone
<supply-and-demand><price-level>
When would prices increase according to Malthusianism?
Mathematician
# When would prices increase according to Malthusianism?

(Asked by: username_0 on 2014-12-15)

Malthusians and Neo-Malthusians believe that, eventually, the population of the earth will be exceed the number of people able to be sustained by the earth's food production. As such, they advocated different forms of population control.  
However, it appears that an increase in the population beyond that of the food supply would cause an increase in the overall **real** price for food.  
Proponents of Malthusianism, evidently, are not waiting for food prices to rise before advocating population control, but I do not see how we should be worried until the **real** price of food increases.  
If Malthusianism is correct, how soon before the population crash would prices begin to rise?

**Tags:** supply-and-demand, price-level
> **Comments:**
> **username_1**: This question doesn't seem answerable, as no accepted economic theories (that I know of) predict such a timeline. Some would predict the possible causal relationship between increased real food prices and decreased fertility, but economics tends not to deal with delusional demographic sensationalism. The world population is ageing quickly with "peak population" having occurred in much of the developed world, and even China's growth rate slowing. Consequently no model would predict a Malthusian crisis, let alone a timeline for it.  
> **username_2**: @JasonNichols I would propose to turn this comment into an answer. Indeed, currently there is a consensus that there is no projected long-term trend for continuously growing population, so the Malthusian argument becomes irrelevant. But I don't see reason to close the question.  
> **username_1**: @AlecosPapadopoulos I didn't vote to close (as a mod I can't vote) I deleted the one-liner non-answer. Ironically, I added mine as a comment because I felt it wasn't up to the standards of a good answer either. :)  
> **username_2**: @JasonNichols Ok, If I want to be strict, I would say that indeed, your comment would be a bona fide answer if it included some references/studies to the fact that we do not expect a constant rise in human population over the long-term. In case you have the time to find some such studies, it would be even better.  
> **username_1**: working on one now, mostly just citing the original work by Malthus, since he explicitly did not predict either a catastrophic rise in food prices or population (in fact his prediction was about the gradual stabilisation of food prices to historic norms and the fact that the quality of life hadn't changed for the peasantry in 2100 years or so).  
> **username_3**: @JasonNichols as a mod, you *can* vote to close: the difference is that your vote is always decisive. The community can reopen a mod-closed question, so there are checks and balances (whereas the community cannot undelete a mod-deleted question). You've been trusted with mod tools and mod powers, and it is ok to use them: when you know a question should be put on hold, please do it. Having said that, it's also good to let the community find its feet and get used to moderating itself too. Do ask in the Teachers' Lounge if in doubt.  
> **username_1**: @EnergyNumbers, that's what I meant by "can't vote". I try to keep a light hand, and let the community sort it out, unless it's really, really egregious, then I'm more apt to just delete. Otherwise I try to comment. I also don't believe all "bad" questions need to be closed, that's why we have downvotes.  
> **username_3**: @JasonNichols If a question needs editing before it's a good question (and I think that applies to this question, YMMV), that is **exactly** what closing is for: it puts the question on hold for a week to give the OP and others chance to improve it. Reluctance to close bad questions will lead to them crowding out good question.  
> **username_0**: @JasonNichols Any help on improving this question would be appreciated. So far, no one has offered any constructive criticism on the question (though the constructive criticism on the prospective answer has been insightful, to me at least).  
> **username_0**: @AlecosPapadopoulos Any help on improving this question would be appreciated. So far, no one has offered any constructive criticism on the question (though the constructive criticism on the prospective answer has been insightful, to me at least).  
> **username_0**: @EnergyNumbers Any help on improving this question would be appreciated. So far, no one has offered any constructive criticism on the question (though the constructive criticism on the prospective answer has been insightful, to me at least).  
> **username_1**: Again, @Mathematician I didn't vote to close. I think the question is broad, but not close worthy. I think it rests on faulty and self-contradicting premises, but that's addressed in the answer, and I don't know that it could be 'edited' to be less broad. I'd say more specific questions like, "Would an increase in population trigger a substantial rise in food prices?" would be better, and could be answered more accurately allowing for discussion of the relationship between money multipliers, velocity of money, demand and price at much greater depth.  
> **username_3**: @Mathematician I don't see a way to salvage it, myself. It's predicated on something that's untrue, and I don't see it as an informative counter-factual either. The Malthusian population growth model turned out to be nonsense, and his model of food growth was no better either.  

---

## 1 answers

### Answer by username_1 on 2014-12-18. Score: 4

This question rests on a few assumptions.

So let's dig into them.

# What Malthus Said

First, the Malthusian collapse you are referring to is similar to the Malthusian Trap, from whence it derives, so let's look at that.

From [Wikipedia](http://en.wikipedia.org/wiki/Malthusian_trap):

> In accordance with the theory, cross-country evidence indicates that technological superiority and higher land productivity had significant positive effects on population density but insignificant effects on the standard of living, during the time period 1–1500 AD. In addition, scholars have reported on the lack of a significant trend of wages in various places over the world for very long stretches of time. In Babylonia during the period 1800 to 1600 BC, for example, the daily wage for a common laborer was enough to buy about 15 pounds of wheat. In Classical Athens in about 328 BC, the corresponding wage could buy about 24 pounds of wheat. In England in 1800 AD the wage was about 13 pounds of wheat. In spite of the technological developments across these societies, the daily wage hardly varied. In Britain between 1200 and 1800, only relatively minor fluctuations from the mean (less than a factor of two) in real wages occurred in Britain. They peaked at around 1450 and in 1800 they were actually significantly worse.

So to go back to the source, Malthus didn't predict a population explosion at all (or food price rises for that matter). In fact, his theory was specifically that population growth fluctuated with economic development such that the prices of wheat (in terms of wages) remained relatively stable over two millennia.

This was known as the Malthusian Trap, where technological advancement would always be matched by (not exceeded by) population growth, resulting in the stagnation of living conditions.

Since the time of Thomas Malthus, new evidence has emerged that, while the trap may exist, many societies break out of it, and achieve explosive growth in living conditions. This is generally termed, the "breakout". In *A Trap At The Escape From The Trap?*$^1$, [Andrey Korotayev](http://en.wikipedia.org/wiki/Andrey_Korotayev) suggests that this breakout leads to social upheaval, and may have played a role in events like the revolutions in Latin America, or possibly even the formation of the US. Unfortunately if we delve too far down the social macroevolution road we wind up having to have the [Guns, Germs, and Steel](http://en.wikipedia.org/wiki/Guns,_Germs,_and_Steel) discussion, and that's straying dangerously off topic, though I also want to throw in a reference to [Huntington](http://en.wikipedia.org/wiki/Samuel_P._Huntington), as another great and accessible read on the really big picture.

# But More People...!

But moving back to your assumptions. Let's assume that population and technological growth became uncoupled by the "breakout". Now all of a sudden standards of living are at all time historical highs. Under Malthus we would expect the population growth rate to also be at historical highs.

But it's not.

In fact much of the developed world is at "peak population", facing major demographic shifts as baby-boomers age out of the workforce faster than they are being replaced.
Japan faces a "[demographic crisis](http://www.economist.com/blogs/banyan/2014/03/japans-demography)"[$^2$](http://en.wikipedia.org/wiki/Aging_of_Japan)[$^3$](http://www.wwq.jp/indexfr.html), the [US shows substantial aging](http://www.census.gov/popclock/) and even [China's growth rate has slowed dramatically and is now lower than the US's](https://www.google.com/publicdata/explore?ds=d5bncppjof8f9_&ctype=l&strail=false&bcs=d&nselm=h&met_y=sp_pop_grow&scale_y=lin&ind_y=false&rdim=region&idim=country:CHN:IND:USA&ifdim=region&tdim=true&hl=en&dl=en&ind=false).

In fact, according to the UN, the projected world population over the next several decades looks like this:  
![enter image description here](https://i.sstatic.net/DcCSF.png)

Which you may notice is not an explosive growth. For more information on this, I'll defer to the experts at the Population Division of the Department of Economic and Social Affairs, and their [technical paper](http://www.un.org/en/development/desa/population/publications/technical/2013-3.shtml)

# Cause and also Cause

Lastly, you're assertions rely on the assumption that increased population means food prices go up.

But that's not how numbers work.

Prices are denominated in currency.

More people (without a correlating rise in currency), actually means there's fewer dollars per person. In that scenario, food prices would go **down** (although probably slower than wages), leading to shortages. Price is a way of rationing scarce resources, but it's not the only way. The other way to ration is queueing, or shortage. This is what we see happen in developing nations. Rice is not more expensive, there just isn't enough rice there.

If everyone only has \$5 a rice merchant can't charge \$6/lb, or he won't sell any.

# An Inflationary Theory

In the event that the population increased, **and** central banks also increased money supply, than standard economic models would predict that the prices of all commodities (not just food) would rise, since the relationship to amount of quantity over the amount money would have changed, or roughly

$$\rho (\Delta P\_n, \Delta \frac{M\_0}{Q\_n})>0$$

where $\rho$ is correlation, and $P\_n$ and $Q\_n$ are price and quantity of $n$ respectively. Of note, there is some disagreement o whether $M\_0$ or another measure of money should be used, but prices in the US (as measured by CPI) have a substantial correlation with $M\_0$ ($\rho = 0.46$ for $M\_0$ as compared to $0.086$ for $M\_1$ from 1985-2013)$^3$

This would be conformant with standard economics, and not reliant on a Malthusian population collapse.

The only way we would expect prices to rise dramatically without central bank intervention would actually be **after** the collapse, as people accumulated currency, and would trade more currency for food.

# TL;DR

In the event of a zombie or post-nuclear apocalypse, cash will decline in value relative to commodities, so stock up on rations and bullets because dollars won't help.$^4$

# References

$^1$: Korotayev, A.; et al. (2011). "A Trap At The Escape From The Trap? Demographic-Structural Factors of Political Instability in Modern Africa and West Asia". Cliodynamics 2/2: 1–28.

> **Comments:**
> **username_1**: sadly work sometimes interferes with play. :)  
> **username_4**: This is mind boggling. Amazing!!  

---

