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Thomas Malthus and population growth | Cosmology & Astronomy | Khan Academy

November 4, 2019

The 1700s in Europe
are often referred to as the Age of Enlightenment. It was a time, we’d come
out of the Renaissance. We’d rediscovered science
and reason and in the 1700s, we saw that come about with
even more progress of society. As we exit the 1700s and
enter into the 1800s, we start having the
Industrial Revolution. And people saw the steady
march of human reason, of human progress. And because of this, a
lot of people were saying, hey, humanity will
continue to improve. It will improve
forever, to a point that poverty will go away. We will turn into this
perfect utopian civilization without wars, without
strife of any kind. And there was something
to be said about that. You had significant
improvements. In fact, you had even
more dramatic improvements once the Industrial
Revolution started. But not every one in the
late 1700s was as optimistic. And one of the more famous
not-so-optimistic people was Thomas Malthus,
right over here. And I will just
quote him directly. This is from his “Essay on
the Principle of Population.” “The power of population
is so superior to the power of the earth to produce
subsistence for man, that premature death must,
in some shape or other, visit the human race.” Very uplifting. “The vices of mankind are
active and able ministers of depopulation. They are the precursors in
the great army of destruction, and often finish the
dreadful work themselves. But should they fail in
this war of extermination, sickly seasons,
epidemics, pestilence, and plague advance in
terrific array, and sweep off their thousands
and tens of thousands. Should success still be
incomplete, gigantic, inevitable famine
stalks in the rear, and with one mighty blow
levels the population with the food of the world.” So not so uplifting of a
little quote right over here. But this was his general sense. He lived in a time
where people were being very optimistic
that progress, the march of progress,
would go on forever until we got to some
utopian civilization. But from Thomas
Malthus’ point of view, he felt that if people
could reproduce and increase the population, they
will, that there’s no way of stopping them. So from his point
of view, the way he saw it– so let
me on that axis– let’s say that that
is the population, and that this axis
right over here, let’s say that that is time. So by his thinking–
and everything that he’d seen in reality
up to that point would back this up– that if people
had enough food and time, they would reproduce,
and they would reproduce in numbers that would
grow the population. So in his mind, the population
would just keep on increasing. It’ll just keep on increasing,
until it can’t support itself anymore, until the actual
productivity of the land can’t produce enough calories
to feed all of those people. So in his mind, there would
be some natural upper bound based on the actual
amount of food that the earth could support. So let’s say that
this is– let me do that in a different
color– so in his mind, there was some upper
bound, and once you get to that upper
bound, then all of a sudden, the vices
of mankind will show up. And if those don’t start
killing people, then all of these other things
will, epidemics, pestilence, plague, and then famine. People are actually
starving to death. So in his mind, once you
got to this level, maybe you had a couple of
good crops, people are feeling good about
themselves, they overpopulate. But then, all of a sudden,
you have a bad crop, or because you have
a bad crop, people start fighting over
resources, and wars happen. Or maybe the population is so
dense that a plague develops. And then you have a massive
wave of depopulation. And so you would just
oscillate around this limit. And this limit some people
refer to as a Malthusian limit, but it’s just really
the limit at which the population can
sustain itself. And from Thomas
Malthus’ point of view, he did recognize that there
were technological improvements, especially in things
like agriculture. And that this line
was moving up. He had seen it in
his own lifetime, that this line had moved up. But from his point
of view, however far you moved this
line up, the population will always compensate
for it and catch up to it, and eventually get to
these Malthusian limit. And then the same
not-so-positive things that he talks about
would actually happen. And some people now
say, oh Thomas Malthus, he was so pessimistic. He was obviously wrong. Look at what’s happened. We have so much food on
this planet right now. We’ve gone through multiple
agricultural revolutions, and they are right. In the last 200
years, since Malthus, so since the early
1800s, we really have been able to
outstrip population. So this line up here
has been moving up much faster than
even population. So right now, we actually
do have more calories per person on the
planet than we’ve had at any time in history. But it’s not saying that
Thomas Malthus was wrong, it’s just saying that maybe
he was just a little bit pessimistic in when that
limit will be reached. Now the other
dimension where you might say that he was maybe
wrong was in this principle that a population will
increase if it can increase. If there is food, and if there
is time, people will reproduce. And a good
counterpoint to that is what we’ve now observed in
modern, developed nations. And so this right over here
shows the population growth. I got this from the World Bank. But the population growth of
some modern, developed nations. And you can see the United
States is pretty low, but it’s still positive. It’s still over half a percent. But even that adds up
when you compound it. But if you look over
here, Japan and Germany– and Japan and Germany
have less immigration than the United States,
especially Japan– they are actually negative. So just this population
left to its own devices, especially if you
account for people not going across borders, just
the population itself growing, they actually have
negative growth. So there’s some reason to
believe that this is evidence that Thomas Malthus was wrong,
or not completely right. He didn’t put into account that
maybe once a society becomes rich enough and educated
enough, that they might not just populate the world, or have
as many kids as they want, they might try to
do other things with their time,
whatever that might be. So I just wanted to
expose you to this idea. Time will tell if Thomas
Malthus, if we can always keep this line of food
productivity growing faster than the population. And time will tell whether
our populations can become, I guess we could say,
developed enough, so that they don’t inex–
I can never say that word. They don’t always
just keep growing. Maybe they do become a Japan
or a Germany situation. And the world
population, especially if we have a high
rate of literacy, eventually does level off. So it never even has
a chance of hitting up against that Malthusian limit. But I thought I would
introduce you to the idea, and now you can go
to parties and you can talk about things
like Malthusian limits. And if you want to know
what country is maybe closest to the Malthusian
limit right now– and we’ve talked about this
before– but a good case example is something
like Bangladesh. They are, right now, the
most population-dense country in the world. They have 900 people
per square kilometer. And just to give you a
sense of perspective, that’s 30 times more dense
than the United States is. So if you took every person
in the United States, and turned them into 30
people in the United States, that would give you a sense
of how dense Bangladesh is. And it’s probably due
to a certain degree that it’s a very fertile land. The river delta of the
Ganges essentially makes up the entire country. But they do, they have
in the past, had famines. They’ve gotten a
little bit beyond that. But still, you do
have major problems with flooding and resources. So hopefully they’ll be able
to stay ahead of the curve.


  • Reply Justan Edwards December 28, 2011 at 11:54 pm


  • Reply DAVID BEHAN December 29, 2011 at 12:01 am


  • Reply Pierre-Emmanuel Fobe December 29, 2011 at 12:08 am


  • Reply english2me December 29, 2011 at 12:10 am

    I encourage everyone to watch Zeitgeist Addendum and Zeitgeist: Moving Forward.

  • Reply byteyotta December 29, 2011 at 12:14 am

    @english2me Zeitgeist is a load of bullshit

  • Reply ashrith jilla December 29, 2011 at 12:15 am

    May be you could dig-deep-into something more about how to achieve the malthusian limit or in other words please explain if this limit could be clutched for a balance control for every country to maintain supply and demand crisis.

  • Reply Pierre-Emmanuel Fobe December 29, 2011 at 12:17 am

    Monaco has a higher density. Correct me if im wrong.

  • Reply Petar Dobrev December 29, 2011 at 12:21 am

    @PEFOBE007 Yes, but Monaco is irrelevant in that case. Monaco has 35 000 people, while Bangladesh is around 150 million and the country's territory is pretty much the same as that of the state of Montana. Imagine 150 million people living in Montana.

  • Reply ArtisanTony December 29, 2011 at 12:22 am

    It changed because we observed it.

  • Reply Petar Dobrev December 29, 2011 at 12:23 am

    @PEFOBE007 Ups, sorry not Montana, Montana is too big. I meant to say New York. So image 150 million people in that state.

  • Reply noitnettaattention December 29, 2011 at 12:40 am

    @english2me what r u some kind of zeitgeist bullshit virus?

  • Reply mars Cubed December 29, 2011 at 12:43 am

    Other problems with Malthus;
    Gene pools as population definitions.. thresholds produce extinctions,
    Also, war often leads to population growth.
    ie, Rwanda's birth rate grew after conflict. Rape is a factor, but also people breed while they can & adopt new social strategies, relocation, economies alter. class antagonisms resolve, cooperation, innovation can even discover new resources etc.
    Malthus model does not generate any such complexity, seems like a bland & rather cynical statement.
    ho hum.

  • Reply eatcarpet December 29, 2011 at 12:56 am

    One of the reasons why people don't have kids anymore is because they don't have the time or money to raise kids.

  • Reply RbtV92 December 29, 2011 at 12:57 am

    God, I love Khan! He's a teacher I listen to everyday! I learn something new and expand on other subjects eeryday and the best part is I can never be late to class! Keep going Khan, revolutionize education! Show the world that learning can be fun and interesting on any degree.

  • Reply RbtV92 December 29, 2011 at 12:58 am

    you aught to start a physical school and base your system on your website! how huge would that be?!?!?

  • Reply kroovyandcal December 29, 2011 at 1:03 am

    If we multiply our population by 30, we come up with 9.3 billion

  • Reply rudy berkvens December 29, 2011 at 1:54 am

    An unmasked Malthusianist, why don't you just stick to Maths, where you began? You are wasting Gates' money.

  • Reply rudy berkvens December 29, 2011 at 1:54 am

    Also 100 billion people would be no big deal, it would mean a city like new york the size of the US, without anyone living anywhere else.

  • Reply Melthornal December 29, 2011 at 2:42 am

    @marsCubed Name the population of France before and after WWI.

  • Reply LNOL December 29, 2011 at 2:48 am

    All of you guys who are trying to correct petty errors in the comments section of a YouTube video: Get a life.

  • Reply ben1996123 December 29, 2011 at 3:01 am

    @LNOL o herro der

  • Reply lollykoko December 29, 2011 at 3:10 am

    Industrial agriculture is not a sustainable model. Petroleum based fuels and fertilizers will continue to increase in price as they decrease in availability. It might not come to an end this decade, but when it does, the permaculture homesteader will survive and prosper.

  • Reply timfwater December 29, 2011 at 3:53 am

    @ajn158 Technically- but the top 4 are all high-end metropolitan islands- completely different demographically from Bangledesh… so many can fit in the former b/c they are living in high-rises and skyscrapers… not packed slums. The resource problems facing Bangledesh due to its density wouldn't even on anyone living in Monaco's radar. Between global warming/rising seas, it's low elevation and an extremely dense population- this is not going to be a good century for Bangladesh.

  • Reply english2me December 29, 2011 at 3:57 am

    @byteyotta certainly not all aspects of it.

  • Reply goldensilverstar December 29, 2011 at 4:07 am

    Bangladesh is only good for Fishing

  • Reply pauseTV December 29, 2011 at 5:30 am

    TIME TO PARTY (with Jersey Shore, Khan Academy version) !
    Tan. √ check √
    Clean Shirt. √ check √
    Hair Gel. √ check √
    Conversation starter 7:16 …. √ check √

  • Reply anon anon December 29, 2011 at 5:46 am


  • Reply Khan Academy December 29, 2011 at 5:15 pm

    @ajn158 The other 4 are city-states that don't produce their own food. Bangladesh actually produces most of its own food.

  • Reply Math Test December 29, 2011 at 6:12 pm

    May have been in interesting to introduce some reasons why a population should grow or not. Like the ability of contraception by condom or pill. And that in poorer countries the child's are needed to take care of the parents at some time, in developed countries is that no longer necessary

  • Reply naruto2710 December 30, 2011 at 1:00 am

    is there a second part of this??

  • Reply Cat98 December 30, 2011 at 6:17 am

    More History Please!

  • Reply Hokke88 December 30, 2011 at 8:08 pm

    This is exactly what happens in many animal populations and from there the idea probably originated. Would be interesting to look at the population charts of some African countries e.g. Somalia and Ethiopia with recurring famines.

  • Reply Benito Tonatiuh Rojas Mayorquín January 1, 2012 at 11:44 pm

    I think this is a great video, congratz, I just want to note that the two showed graphs aren't expressed in the same terms, that is, they don't measure the same thing … the result may be the same but the fact is that they are misleading

  • Reply Timothy Diacono January 2, 2012 at 12:42 am

    @ajn158 My island country's in at Number 3!!!

  • Reply gunz543 January 5, 2012 at 7:29 am

    very interesting!!

  • Reply Gatis January 9, 2012 at 8:44 pm

    If you eat a baby, it's ok because you are not hungry anymore and you have saved our civilization.

  • Reply Traders Friend January 19, 2012 at 1:39 am

    I am a huge fan, but wondering about this piece and toying in the back of my mind with the fact that since the gates grant, You may have sold out. Planting depopulation ideas is dangerous, but it seems less threatening if we put some fancy academic terms around it….love most of Your work, but beginning to wonder????????????

  • Reply DEVIL COMMANDER January 19, 2012 at 1:45 am

    thomas malthus was a dangerous man.

  • Reply MrBigEnchilada January 19, 2012 at 5:29 am

    ok ok, how about the millions who die in africa every year due to overpopulation, and not just in africa, those in asia, south america, and those who are very poor in the u.s.

  • Reply MrBigEnchilada January 19, 2012 at 5:31 am

    @halflifeproductionz how was he dangerous, he suggested something like sustainability or we can call biomass, which we totally like to ignore today.

  • Reply Mɛᴛʀᴏ Orlɛanž January 20, 2012 at 11:39 pm

    @ArtisanTony That's exactly what I was thinking.

  • Reply P.S.Y. January 24, 2012 at 11:32 am

    population growth is exponential/geometric, not linear.

  • Reply gdmk1000 April 9, 2012 at 4:32 am

    It doesn't matter how dense you are, it matters how free a market you have…
    Given a free enough market productivity rises (much) more then enough.

  • Reply Satan's Apple Dandies April 15, 2012 at 1:36 pm

    Why not just invest in underwater colony tech. I actually made a whole Idea as how people can live independantly and sustainablly. underwater. The only problems (that I can recall) is a nitrogenized atmosphere.

  • Reply Madeleine McCormack June 5, 2012 at 9:21 am

    that voice is familiar…any chance the guy lecturing is a fellow who lectures IR in japan??

  • Reply Ashitaka255 July 3, 2012 at 11:22 am

    I think Malthus is still right, while we do not reproduce as rapidly and food is plentiful we consume other resources which are quite limited like oil and coal.

    I think if the entire world became like the west our Malthusian limit wouldn't go away, if we all wanted to keep the western lifestyle that allowed the low population growth (without a government mandate) we'd have a different struggle – energy production.

  • Reply The Rain Shimmers July 4, 2012 at 12:10 pm

    This was surprisingly not-helpful to someone who has actually studied these issues.
    Why focus on the unsupported ideas of a single non-professional economist who has been wrong in all of his predictions when there are real and more relevant alternative theories out there?
    Neoliberalism is responsible for late 20th century starvation around the world. Capitalism forces many to live in rags so a few can own mansions alone and sad.

  • Reply polka23dot July 22, 2012 at 12:22 am

    Global food production has peaked due to soil erosion, urbanization, and salination of irrigated farmland. High yields of modern agriculture are dependent on petroleum, which has also peaked. The high yielding seed varieties respond strongly to petroleum-based chemical fertilizer. Corn yields would fall from 130 to 30 bushels per acre in the absence of chemical fertilizers, pesticides, and petroleum powered irrigation. If we do not reduce human population, mass starvation cannot be prevented.

  • Reply t3h plonker August 9, 2012 at 6:08 pm

    Africa will triple it's population in the next 20 years, from 1 billion to three!! And the famine and wars we have now will get worse. unfortunately even with the amount of population decrease Germany has they wont be able to accommodate them all. very sad. we should stop sending food as it's like putting a band aid on a gangrenous wound.

  • Reply t3h plonker August 9, 2012 at 6:08 pm

    these people need education and employment not the means to have more children with us frantically trying to save every one of them. and to what end? so they can live in poverty? were there is constant war for resources and lack of food ? that's a fait more cruel than death.

  • Reply Barry Mitchell October 25, 2012 at 10:49 pm

    There is the food line but then we have the climate line which a lot of scientists would put us above the amount of fossil fuels we should be buring, how is that going to decrease if the population doubles over 40 years or something like that? Most of the world's problems comes down to there being too many people but the argue against this idea using their emotions instead of common sense. It's in the state now where we can't do anything about it but we can certainly be aware of population.

  • Reply technatezin November 13, 2012 at 2:49 am

    5:45 of clip:

    Modern industrialized societies always require more resources per person to keep the society functional when compared to non-industrialized society. This means population and production increases in developed society limits the population because it's much harder for the individual in developed societies to acquire the resources to keep the production expansion going than it is for the average individual in non-industrialized societies where resources are scarce and life is cheap.

  • Reply Michael Lyner November 14, 2012 at 2:51 am

    I wonder if he, and the illuminati would agree with homosexuality..

  • Reply Michael Lyner November 14, 2012 at 2:58 am

    maybe the population chart yo showed is negative because of agenda 21…
    maybe some powers that be agree with malthus and are tang measure to prevent him from being right..think about all the conspiracies about aids being man mad,,swine flu, food being controlled and poisoned, water having fluoride etc..I think its a pretty feasible counter argument to your chart. Im not saying this is fact, but its something to think about..shit even bill gates talked about a depopulation plan through vaccines.

  • Reply ufa January 6, 2013 at 9:51 pm

    My teacher based his lesson on this video xd

  • Reply Tourettes Orc February 3, 2013 at 8:06 pm

    Interesting fact; In demonology, Malthus (also Halphas, Malthas, or Malthous) is an Earl of Hell, commanding 26 legions of demons, who is said to have a rough voice when speaking. He is often depicted in the shape of a stork.

    Malthus builds towers and fills them with ammunition and weapons, an armorer of sorts. He is a prince of Hell. He is also said to send his legions into battle, or to places designated by higher commanding demons.

  • Reply aizhol April 21, 2013 at 8:40 am

    Thomas Malthus underestimated the power of condoms!

  • Reply Engineer 314 May 8, 2013 at 4:42 am

    Okay, so this video shows that Japan and Germany is definitely not growing in population size like Malthus thought, but what about India and China? Those two countries have pretty much many of the problems Malthus hypothesized, or at least in the countryside, which is where Malthus thinks is where most of the population growth occurs.

  • Reply Chris Peters June 7, 2013 at 6:38 am

    electricity grids, consumer diets, broadcast programming, military technology

  • Reply bullseye140 July 7, 2013 at 6:55 pm

    In China though, the food supply is going up but the birthrates are going down. Same thing is happening in India, so Malthus was wrong.

  • Reply Chibi Chats! July 11, 2013 at 6:03 pm

    The interesting thing about the start of this video is we are actually getting to the point where food, water and energy will be cause of famine and many wars.

  • Reply Linda M September 23, 2013 at 3:34 pm

    to everyone that has commented on this video…. Yall have just helped me with my assignment *kisses* *kisses* *hugs* <3

  • Reply 4vonwarschau September 24, 2013 at 7:31 pm

    Thanks man!

  • Reply AntiTroll101 November 5, 2013 at 2:30 pm

    The reason the birthrate is going down in China is because they have a law there saying that a family can only have one child. Its great. Living conditions are improving, and food supply is being replenished. Now if only the rest of the world could follow suit.

  • Reply Colorado Hillbilly August 29, 2014 at 4:24 pm

    word i agree with all of you but think about the extra workers you would have that's more beggars or farm hands or something that could be used to make more money???? that's what i would want to know???? 🙂

  • Reply NathanWin November 16, 2014 at 8:52 pm

    hahaa nice!

  • Reply Arseniy Cassidy November 24, 2014 at 2:14 pm

    it is now holland which is most dense

  • Reply Dennis Tedder February 25, 2015 at 1:47 am

    The good thing about maths…it's irrefutable. And this…it's all math. There were 2 B when I was in college in '73. Same stuff, just more people and more hungry mouths.

  • Reply vic oilsteems April 30, 2015 at 5:34 pm

    Mr and Mrs Duggar are ignorant fucks.

  • Reply Blahblahblah14898 May 7, 2015 at 2:04 am

    your voice is annoying

  • Reply Jerry Trust June 28, 2015 at 9:34 pm

    how can you talk about the line, and not use the words "carrying capacity"

  • Reply SeiryuNanago February 26, 2016 at 4:15 pm

    Even if population stop increasing, societies keep consuming more resources once they are really developed technologically. At some point, every country may have a consumption similar to the US or Uk or France, can the earth accommodate such consumption? Maybe his theory still have some relevance in that way?

  • Reply Roses and Songs April 8, 2016 at 6:02 am

    The US has 5 or 6 percent of the world population and it consumes 25 percent of the world's ressources and it is probably valid for us in Canada too but nowhere else in the world is it so unbalanced. As unpleasant as it may sound, our irresponsible consumption makes us responsible for the lack of ressources in other countries like India for example. More money = more education = lower fertility rates = world population kept in check, but are we willing to stop filling up the Hummer for a Sunday afternoon ride to nowhere? Do we understand that the earth's ressources are limited? Not really, we are FREE and no one can tell us what to do, the rest of the world be damned. The only way for some to get rich is for others to be poor… but it's always been that way hasn't it?

  • Reply bruno Ad bruno Ad2016 May 9, 2016 at 2:11 pm

    i read the book Freakonomics !

  • Reply Aron William Lynch July 17, 2016 at 9:56 am

    Robert is right in my opinion and that's why some countries may show a negative growth in births because of this very fact, that the population is getting too big. So it's showing the effects of population control. Malthus is right and by 2050 the population will be about a billon but just my opinion.

  • Reply Bill Zander October 8, 2016 at 1:27 pm

    So the Khan Academy has a smartboard and knows how to use it. This was significantly more boring than any lecture I got at any point in my high school career. At least those lectures featured a human being with whom I could interact. I imagine this is the 'homework' of a flipped classroom, but seriously, this will not hold a teenagers attention.

  • Reply Kix November 8, 2016 at 4:56 am

    sounds like the apocalypse in the Super Natural series

  • Reply Lance Winslow February 10, 2017 at 8:07 am

    Thomas Malthus should have founded the Club of Rome? He thinks just like them, but didn't understand all the potential options humans will have by the time we run out of space to grow our food. In studying this I have several concepts preventing this problem.

  • Reply blagovest doganov October 6, 2017 at 8:10 am

    It's important to point out that Developed Countries have much slower pop growth, due to the fact that people in general become much more specialized in jobs and have to dedicade much more time and energy into their career, rather then producing a family therefore contributing to pop growth. Also Keep in mind that having a 1 child, is a negative growth, having 2 children is neutral-no growth, and only by having 3 children or more in a family, does the actual population increase. It's not that people don't want to extend population in developed countries (they dont care about demographics), they just dont want to handle so many children.

    Also, thank you for this video.

  • Reply Thjeok Thjeok January 9, 2018 at 12:37 am

    you forgot that europe at one time had overpopulated to its own detriment [ plaque ] – it taught them a better way . Better infrastructure is the most important part .

  • Reply Jeffrey Hawthorne Goines February 27, 2018 at 8:59 pm

    Excellent presentation, but I do not share the view of the author on the 1800's as a time of Utopianism; if indeed this was one well illustrated tendency, it was not the only one and other currents of thoughts existed which were very far from Utopian. The most obvious would be the gross materialism and selfishness which developed, but there are other signs of activities very hostile to humankind, such as the emergence of enormously decimating wars, and other odious phenomena such as revivified ugly antisemitism. As far as what Dennis says, I profoundly disagree; maths are far too abstract to ever really represent the experience of life

  • Reply Hiba Arif March 27, 2018 at 6:54 pm

    thank you soo much …

  • Reply Ximena Pena August 23, 2018 at 1:17 am

    your introduccion is so longgggg…

  • Reply God November 18, 2018 at 7:35 am

    I found this summary much better than crash course histories mess of an attempt. I know this was made in 2011 but right now Monaco is the most dense at around 26k ppl per sq km so I doubt Bangladesh was the most dense 7 years ago compared to Monaco and some of the island nations in Caribbean.

  • Reply CatPaws January 9, 2019 at 5:56 am

    Oglan olmuyub ki Thomas Malthus

  • Reply Rhys Lewis January 9, 2019 at 6:55 pm

    if you are searching for this quote on the original essay , it is found chapter 7 page 44.

  • Reply Feynstein 100 June 4, 2019 at 12:31 pm

    I think the underlying logic of Mathus' argument is actually sound. The amount of resources on earth is finite. But provided people continue to reproduce indefinitely, the population will grow exponentially, until it is forced to stop growing by the limit. There does exist such a limit for Earth. It's just higher than Malthus had anticipated.
    The second problem with this is that people did not continue to reproduce indefinitely. Because of the industrial revolution, people urbanized rapidly and people in urban areas have incentives to produce fewer children, since in cities, children are liabilities, not assets, unlike in farms. Hence the population growth rate decreased, instead of constantly increasing, as Malthus had anticipated.

  • Reply Andrew N September 14, 2019 at 3:53 pm

    malthus was right, but too early.. our world population is at 7.5 billion, moving to 9 then 10 billion, meanwhile the world is strained by just too many people competing for the same scarce resources

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