Search FQXi

If you are aware of an interesting new academic paper (that has been published in a peer-reviewed journal or has appeared on the arXiv), a conference talk (at an official professional scientific meeting), an external blog post (by a professional scientist) or a news item (in the mainstream news media), which you think might make an interesting topic for an FQXi blog post, then please contact us at with a link to the original source and a sentence about why you think that the work is worthy of discussion. Please note that we receive many such suggestions and while we endeavour to respond to them, we may not be able to reply to all suggestions.

Please also note that we do not accept unsolicited posts and we cannot review, or open new threads for, unsolicited articles or papers. Requests to review or post such materials will not be answered. If you have your own novel physics theory or model, which you would like to post for further discussion among then FQXi community, then please add them directly to the "Alternative Models of Reality" thread, or to the "Alternative Models of Cosmology" thread. Thank you.

Contests Home

Current Essay Contest

Contest Partners: Jaan Tallinn, The Peter and Patricia Gruber Foundation, The John Templeton Foundation, and Scientific American

Previous Contests

Undecidability, Uncomputability, and Unpredictability Essay Contest
December 24, 2019 - April 24, 2020
Contest Partners: Fetzer Franklin Fund, and The Peter and Patricia Gruber Foundation

What Is “Fundamental”
October 28, 2017 to January 22, 2018
Sponsored by the Fetzer Franklin Fund and The Peter & Patricia Gruber Foundation

Wandering Towards a Goal
How can mindless mathematical laws give rise to aims and intention?
December 2, 2016 to March 3, 2017
Contest Partner: The Peter and Patricia Gruber Fund.

Trick or Truth: The Mysterious Connection Between Physics and Mathematics
Contest Partners: Nanotronics Imaging, The Peter and Patricia Gruber Foundation, and The John Templeton Foundation
Media Partner: Scientific American


How Should Humanity Steer the Future?
January 9, 2014 - August 31, 2014
Contest Partners: Jaan Tallinn, The Peter and Patricia Gruber Foundation, The John Templeton Foundation, and Scientific American

It From Bit or Bit From It
March 25 - June 28, 2013
Contest Partners: The Gruber Foundation, J. Templeton Foundation, and Scientific American

Questioning the Foundations
Which of Our Basic Physical Assumptions Are Wrong?
May 24 - August 31, 2012
Contest Partners: The Peter and Patricia Gruber Foundation, SubMeta, and Scientific American

Is Reality Digital or Analog?
November 2010 - February 2011
Contest Partners: The Peter and Patricia Gruber Foundation and Scientific American

What's Ultimately Possible in Physics?
May - October 2009
Contest Partners: Astrid and Bruce McWilliams

The Nature of Time
August - December 2008

Forum Home
Terms of Use

Order posts by:
 chronological order
 most recent first

Posts by the author are highlighted in orange; posts by FQXi Members are highlighted in blue.

By using the FQXi Forum, you acknowledge reading and agree to abide by the Terms of Use

 RSS feed | RSS help

Don Chisholm: on 5/30/14 at 1:45am UTC, wrote Alan, it is great to see a focus on one of the large invisible elephants...

Margriet O'Regan: on 5/29/14 at 6:53am UTC, wrote Hello Allan You've picked an aspect of the problem from which most steer...

Don Limuti: on 5/26/14 at 21:31pm UTC, wrote Hi Alan, I second Peter's opinion: Great essay, much needed, very well...

Anonymous: on 5/22/14 at 6:10am UTC, wrote Alan, I still don't manage getting my vote confirmed. Perhaps this...

Eckard Blumschein: on 5/17/14 at 8:48am UTC, wrote I just tried in vain to rate the essay 10 because it dared to address a...

Israel Perez: on 5/13/14 at 14:30pm UTC, wrote Dear Alan Your work is well written and informative. I do agree that...

Neil Bates: on 5/11/14 at 0:11am UTC, wrote Alan, I think your diagnosis is essentially correct. And yes, we will IMHO...

Charles St Pierre: on 5/7/14 at 5:07am UTC, wrote Dear Alan, I found your essay very informative. I agree on the necessity...


Georgina Woodward: "Be careful, there are many people who are not who they pretend to be." in Global Collaboration

Georgina Woodward: "The preceding explanation of wavefunction collapse is, I think,..." in Consciousness and the...

jim hughes: "I'm not a mathematician. So what I see here is some smart people who..." in Consciousness and the...

Steve Dufourny: "Hello FQXi, the members and all, I try to do my best to unite and convice..." in Global Collaboration

Georgina Woodward: "Broken machine: What do[es] I see next? The I that was, E.I, has not been..." in The Room in the Elephant:...

Lorraine Ford: "Hi Stefan, I hope that a good leader, and a good political party, is..." in The Present State of...

Lorraine Ford: "We live in an age of computing. But physics, mathematics and philosophy,..." in The Present State of...

Georgina Woodward: "I've copied the comment to the thread where it belongs. This orphan can be..." in The Room in the Elephant:...

click titles to read articles

Good Vibrations
Microbead 'motor' exploits natural fluctuations for power.

Reconstructing Physics
New photon experiment gives new meta-framework, 'constructor theory,' a boost.

The Quantum Engineer: Q&A with Alexia Auffèves
Experiments seek to use quantum observations as fuel to power mini motors.

The Quantum Clock-Maker Investigating COVID-19, Causality, and the Trouble with AI
Sally Shrapnel, a quantum physicist and medical practitioner, on her experiments into cause-and-effect that could help us understand time’s arrow—and build better healthcare algorithms.

Connect the Quantum Dots for a New Kind of Fuel
'Artificial atoms' allow physicists to manipulate individual electrons—and could help to reduce energy wastage in electronic devices.

September 29, 2021

CATEGORY: How Should Humanity Steer the Future? Essay Contest (2014) [back]
TOPIC: Just Too Many People: Towards a Sustainable Future Earth by Alan M. Kadin [refresh]
Bookmark and Share
Login or create account to post reply or comment.

Author Alan M. Kadin wrote on Mar. 4, 2014 @ 16:14 GMT
Essay Abstract

Our modern civilization is built on cheap energy from fossil fuels, which produces carbon dioxide, which produces global warming. The only way to avoid catastrophe is to shift away from fossil fuels to solar and nuclear energy, well before all fossil fuel reserves have been burned. But this transition cannot be achieved with a projected global population of 10 billion (10B); we need to return to a level of 100 to 200 years ago, when the population was ~1-2B. A peaceful transition is possible only if humanity collectively takes ownership of the problem.

Author Bio

Alan M. Kadin is an applied physicist (PhD Harvard 1979), who has worked in both industry and academia, and is now living in Princeton Junction, New Jersey, USA. Dr. Kadin’s primary research field has been superconducting devices, but he also has longstanding interests in the foundations of physics and in futurology. He submitted two essays to previous FQXi contests: and

Download Essay PDF File

Bookmark and Share

Joe Fisher wrote on Mar. 7, 2014 @ 16:13 GMT
Dear Doctor Kadin,

I found your essay quite an interesting read. May I make a comment about something you seem to have overlooked?

Man is a life form. Man is not the only form of life. Indeed, man is the worst form of life for the only thing man has done is to destroy life. It seems to have escaped your attention completely that the only way any form of life can continue to exist is by consuming life. Life is immortal. There may be 7 billion humans presently alive. How many blades of grass are there? How many insects? How many gargantuan creatures lurking in the depths? What should happen after a man dies? Well of course he is supposed to be eaten up by the maggots and recycled. Natural immortal continuation was not good enough for man. Instead man has resorted to poisoning all of the waters, and all of the land, and all of the air with chemicals. Now he is busy building robots with artificial brains, which man thinks will be able to survive the toxic milieu he has created. Fortunately, nature is unique. Nature will soon easily produce a “new” life form that will probably get rid of man as we know him, and replace him with a life form a bit less stupidly destructive.

Bookmark and Share
report post as inappropriate
Author Alan M. Kadin replied on Mar. 7, 2014 @ 17:38 GMT

I'm afraid I can't agree with your comment that "man is the worst form of life".

Just because I am arguing for a reduced human population does not mean that I object to people, or that I object to children when I suggest fewer of them. On the contrary, humans are unquestionably the dominant life form on this planet, and will remain so for the foreseeable future. As the dominant life form, it is our responsibility to take better care of this planet; it is the only one we have. While I am pessimistic for the near term, I am optimistic about the long-term survival of a thriving human civilization, together with a representative sampling of other animals, plants, and microorganisms.

Alan Kadin

Bookmark and Share

Joe Fisher replied on Mar. 10, 2014 @ 16:35 GMT

Recently, anonymous commanders of the United States Navy, and The Russian Navy parked several atomic powered submarines under both the Arctic and Antarctic ice shelves for several months. Indeed, the submarines may still be patrolling those areas regularly. Surprise! The ice caps are melting. Big Military has no conscience.

Bookmark and Share
report post as inappropriate

Tihamer T. Toth-Fejel replied on Apr. 29, 2014 @ 03:09 GMT
A few nuclear submarines parked under the polar ice melted them?

Can you estimate the number of BTUs required, compared to the number of BTUs released by nuclear subs?

Did they do the same thing back in

1962 too?

Bookmark and Share
report post as inappropriate

Eckard Blumschein wrote on Mar. 14, 2014 @ 05:28 GMT
Dear Alan,

You wrote: "Is there any hope for a sharp reduction in the birth rate?

I believe that there is, given that such reductions in fertility follow on population trajectories that are already present in many developed countries. Historically, women married young and started having children immediately. Now the trend is for women to delay marriage and child-bearing while they...

view entire post

Bookmark and Share
report post as inappropriate
Author Alan M. Kadin replied on Mar. 14, 2014 @ 15:48 GMT

Thank you for your comments. My intention in my essay is to suggest that there is hope for the future, but not that the transition will be easy. Modern industrial civilization was built on multiplying human power using cheap fossil fuels, increasing the population and making global warming inevitable. We need to develop inexpensive alternative energy sources, without jeopardizing our food supply. These and other global problems will be more tractable if the global population is smaller rather than larger. This may seem obvious, but most people just don't think about it. That needs to change.


Bookmark and Share

Eckard Blumschein replied on Mar. 14, 2014 @ 18:14 GMT

My essay is not yet finished. I am sure it will be even less welcome than yours because I was born in Berlin in 1942, faced the bankrupt of various ideologies, and am now in position to address what I consider fallacies. What religion, what state do you expect preaching to have less than two children?


Bookmark and Share
report post as inappropriate

Member Dean Rickles wrote on Apr. 9, 2014 @ 10:30 GMT
Dear Alan,

You write that "In conclusion, global warming and resource limitations make it imperative that the global population be decreased as soon as possible". I'm not sure there are many that would disagree with this (it's presumably amongst the premises on which this essay topic was based), but the question is: how should that happen? What process could bring it about that people alter their ways to such an extent that rather the 10Billion we get down to 1Billion? And what grounds do you have for being optimistic in the long-term? What is that belief based in?



Bookmark and Share
report post as inappropriate
Author Alan M. Kadin replied on Apr. 9, 2014 @ 13:35 GMT

Thank you for your interest in my essay. I agree that the need for decreasing population is obvious, but most of the world does not agree that this is the case. Furthermore, there is a broad unwillingness even to talk about the issue, perhaps for fear of sounding like discredited concepts of eugenics.

Why am I optimistic in the long term? Worldwide urbanization has already led to sharply reduced fertility rates. In the developed countries, native-born populations are already decreasing. What is needed is the universal recognition that such population decreases are essential for the foreseeable future, if humanity is to have a future. Notwithstanding widespread irrational behavior in the past and present, I believe that human societies have the capacity for rational behavior.


Bookmark and Share

Eckard Blumschein replied on Apr. 9, 2014 @ 14:21 GMT
Dear Dean,

I asked Alan: "What religion, what state do you expect preaching to have less than two children?" Why did he not yet reply? Why did you in principle reiterate my question?

Well, a honest consequent answer might presumably be amongst the premises on which this essay topic was based. Do you, did those who formulated that premise expect a miracle? If so you may believe in cold fusion or in 100 billion people getting happy after moving to elsewhere in our universe or even in parallel anti-worlds. I wonder if FQXi is really just interested in pure fiction.

My essay is now readable [\link]. While I anticipate almost nobody spontaneously agreeing with those from which I borrowed my perhaps compelling but extremely hurting arguments, e.g. Albert Michelson, Alfred Nobel, Archimedes, Aristotle, Claude Shannon, Euclid, Galileo Galilei, Heraklit, Isaac Newton, Karl Popper, and Otto de Guericke, I do also not expect you in position to refute at least the most important ones.

Sorry for being blunt.



report post as inappropriate

Member Tommaso Bolognesi replied on Apr. 9, 2014 @ 14:28 GMT
Dear all,

I am also optimistic about a decreasing population in the long term, not much for the capacity of rational behavior of human societies, but for a number of self-regulatory mechanisms that (will) emerge in the complex system of humanity. You gave already good examples, such as the evolving life-styles in densely populated urban areas. I would also add the increased acceptance of families formed by couples of the same sex. Of course, the adjustments to a better demographic regime may imply humanitarian crises, massive death, etc. But events that appear catastrophic from the perspective of individual persons or communities, appear minor physiological adjustments when looking at humanity as a whole super-organism.

Having said this, I tend to believe that in the VERY, VERY LONG term, the fate will be to keep growing, and to spread out of this planet. Thus, I agree with the nice essay by Ashworth that, out of three possible scenarios (`return to a preindustrial state, continuation of growth, or halting of growth at close to its present level`) selects the continuation of growth as the most realistic.


Bookmark and Share
report post as inappropriate

Ioana Petre wrote on Apr. 18, 2014 @ 19:41 GMT
I enjoyed reading your essay. I have one question, though. How does your view on population growth reconcile with life extension technologies?

Bookmark and Share
report post as inappropriate
Author Alan M. Kadin replied on Apr. 19, 2014 @ 14:42 GMT

Thank you for your interest in my essay.

In response to your question, if people were to live forever, the population would never decrease. However, my expectation is that life extension will soon be approaching practical limits, and will not have a major impact on world population. The elderly do not have significant numbers of children.


Bookmark and Share

Vladimir Rogozhin wrote on Apr. 20, 2014 @ 20:51 GMT
Dear Alan,

I read your in-depth analytical essay with great interest. I agree with most of the conclusions. Requires deep expert assessment of global existential risks, their wide-ranging, discussion and creation of programs to minimize them. It requires common efforts of the public, governments and businesses . I think that optimism about the population can give especially wide education and creation of modern pension systems. Schools should prepare not workers and professionals, but creative individuals. Internet and new information technologies provide new opportunities for all Humanity more reliable steer spaceship named "Earth" .

I wish you good luck!

All the Best,


Bookmark and Share
report post as inappropriate

Anonymous wrote on Apr. 21, 2014 @ 02:51 GMT
Hi Alan,

a very informative and easy to read essay. You have very clearly set out the many issues but spent less time on giving solutions.I absolutely agree that population is one of the biggest problems. So it is good that you picked that one for particular attention.

Re. The one child policy, there is an alternative worth considering. Not all people have the same drive to bear and raise children.Some people make better parents than others. There are many unwanted children brought into the world. Wouldn't a better solution be to give people the choice to be parents or not but if they choose parenting they must be deemed physically and mentally suitable and undergo training. The population could be temporarily sterilized until an application is accepted. Perhaps they must also pay for reversal of their sterilization, as another deterrent. All children will then be raised by parents who want them, who can carry out effective nurturing and socialization of the children. The population will decline as many never apply for procreation and do not get their sterilization reversed. Admittedly a one child policy is more easily implemented and we know it works from China's experience. Though with that policy there will be heartbreak for those who would desperately like more children, while others may only have one child because they are allowed one child.

A very well written essay. Good luck, Georgina

Bookmark and Share
report post as inappropriate

Anselm Smidt wrote on Apr. 22, 2014 @ 16:19 GMT
Das ist genau das, was schon ist.

Bookmark and Share
report post as inappropriate

Tihamer T. Toth-Fejel wrote on Apr. 29, 2014 @ 03:49 GMT
Dear Alan,

If Malthus has been wrong for 200 years, what evidence is there that he will suddenly become correct? In his 1970s book, Erlich predicted food riots in the USA by the 1980s; plus he lost his bet with Simon over metal prices. Why do people keep pushing fatally incorrect theories?

It's because they can't imagine exactly how we'll get past fossil fuels. Understandable, but even a Saudi oil minister observed that "the Stone age didn't end because we ran out of stones, neither will the oil age end when we run out of oil."

Take a look at Ray Kurzweil's observation regarding solar power, which has been doubling capacity for the last two decades, and approaching cost parity. Within five years, we will be marking the obvious beginning of the end of the oil age. By 2030 almost all of the world's energy will be met by solar. See Surging Solar

Much of the problem is because ecologists don't understand economists (and vice versa). Interestingly, there was a recent article in the WSJ about exactly this subject, written by someone who has lived in both camps. See The World's Resources Aren't Running Out

As I pointed out in my essay Three Crucial Technologies , nanotechnology, extraterrestrial development, and artificial wisdom must be fully developed for us to survive. The first two solve all the problems you brought up in your essay. The last technology will be the most difficult to achieve--by far.

Bookmark and Share
report post as inappropriate

Petio Hristov wrote on Apr. 29, 2014 @ 07:04 GMT
Dear Alan M. Kadin

I read with great interest your essay, because it refers to the inevitability of Global warming although in a very different point of view. I like that you use the persuasiveness of statistics i.e. numbers for the defense of your thesis namely the necessity to decrease the human population in future. I like the way you propose to solve the problem – in a long term and relatively harmless manner. I also support your idea of introducing new alternative energy sources which is essential to be made a priority. I think that the proof that you introduce and so elegantly upgrade is an expression of a deep study which deserves attention and assessment.

Petio Hristov

Bookmark and Share
report post as inappropriate

Peter Jackson wrote on Apr. 29, 2014 @ 19:44 GMT
Dear Alan,

That was a very well argued representation of that case. The only think it missed was instructions to the helmsman of how to achieve it, wherein lies the tricky bit. However Judy Nabb addressed that quite bravely and well considering eugenics, and you used the space limit well for what you did cover.

I am however intrigued as to whether you would favour any particular solutions? The China model has exposed many problems and now been relaxed as I understand it.

I must admit, the option of 'virtual children' came to mind (available in non nappy soiling variants!)

I also suspect a good argument could be made for technology continuing to keep pace for some time. Just a bit of climate change, improve food chain, desalination and solar pv efficiency and 10bn people could easily fit into the empty quarter of Saudi Arabia, the Australian outback or Antarctica at moderate density!

But really I agree with your argument. We must recognise some limit as we really don't know what might tip the balance, as I argue myself.

Great essay, much needed, very well done. Your present score is an injustice. You must have been zapped by the trolls as I first was. What comes down must go up...


Bookmark and Share
report post as inappropriate

Charles Gregory St Pierre wrote on May. 7, 2014 @ 05:07 GMT
Dear Alan,

I found your essay very informative. I agree on the necessity of reducing the earth's population. Humanity taking ownership of the problem, unfortunately, is not even the first step.(Who knows, this contest may be the first step?!) I wish, however, that you had provided a more detailed prescription.

Let me bring to your attention reference 4 to my essay: "A Minimal Model for Human and Nature Interaction." I think you will find it very interesting. (And of course, I hope you will read and enjoy my essay.)

Good luck in the competition.

Charles Gregory St Pierre

Bookmark and Share
report post as inappropriate

Neil Bates wrote on May. 11, 2014 @ 00:11 GMT
Alan, I think your diagnosis is essentially correct. And yes, we will IMHO probably need some nuclear power for awhile (already use it of course, my own power comes from a nearby plant.) Unfortunately, it is unrealistic in practice to expect humanity to reduce population to 1-2 billion, so we are pragmatically faced with managing a situation closer to the current population, for awhile at least. My own essay deals with possible improvements to the human mind, in advance of particular objective policy ideas. Perhaps one application of the willpower training I advocate will be smaller families, as well as less consumption.

PS: No big deal, but as a cute observation, my spell checker flagged IIMO to be "IMHO" - they got that web slang in there, LOL (which did NOT make it ...)

Bookmark and Share
report post as inappropriate

Israel Perez wrote on May. 13, 2014 @ 14:30 GMT
Dear Alan

Your work is well written and informative. I do agree that population is a problem although I am not sure for how long the planet can sustain the current population; I guess this would require a deep study about natural resources for the future. I'm not sure if reducing the population to 1B or 2B is a long term solution because as far as I know the current food productivity is enough to feed three times the current population. So, in principle, the planet can sustain at least 21 Billion people (but for how long?) and according to predictions the population for the rest of the century will stabilize to around 12 B. By then, we will improve our technology to cope with the problems we have now.

So, I think the problem is not productivity but a balanced distribution of resources. Developed countries waste a lot resources, whereas some developing countries are suffering from famine, etc.

Another point is that I don't have clear what would be your specific proposal. Do you propose that governments impose laws restricting the number of children per family, similar to China? I do not think people will be happy with a restriction like this. In my view, the population will reduce by `natural' processes.

Best Regards


Bookmark and Share
report post as inappropriate

Eckard Blumschein wrote on May. 17, 2014 @ 08:48 GMT
I just tried in vain to rate the essay 10 because it dared to address a taboo, while I am nonetheless disappointed because some reiteration of old wrong criticism against main arguments was perhaps not consequently enough rejected by Alan Kadin.


Bookmark and Share
report post as inappropriate
Anonymous replied on May. 22, 2014 @ 06:10 GMT

I still don't manage getting my vote confirmed. Perhaps this doesn't matter much because too many possible voters are indoctrinated. They know that the prediction by Malthus did not fulfill so far. And they fear you will come close to eugenics, the study of how to improve the human race by carefully selecting parents who will produce stronger children. What narrow-minded nonsense!

Is there nobody in position to realize what a truly foundational questions is? Definitely it is impossible to escape from the consequences of being narrow-minded unless questioning whether traditional religious, national, humanitarian, or currently accepted as scientific values are really basic ones. Is it really a humanitarian freedom to have as many children as possible?

In my essays I reminded of Galileo Galilei, Claude Shannon and Alfred Nobel who would perhaps not agree much with all those who are in this contest on top.

Well, we might disagree about some details. For instance, I doubt that nuclear fission is a responsible solution, and I see neither tokamak nor Wendelstein promising principles for nuclear fusion and cold fusion an obvious illusion.

However, you Alan are certainly correct: Unlimited growth of the world's population is impossible. There is an optimal size of population. Discoveries, inventions and other contributions to worldwide progress rather than well-meant suggestions presented in our essays are steering this optimum. Most essayists failed to realize this in their essay and in their vote too.


Bookmark and Share
report post as inappropriate

Don Limuti wrote on May. 26, 2014 @ 21:31 GMT
Hi Alan,

I second Peter's opinion: Great essay, much needed, very well done. Your present score is an injustice.

I personally believe that solar and wind is going to get a big boost via really large flow batteries. However, all your points are valid, and population is definitely in the mix.

Time to help remedy the injustice.

Don Limuti

Bookmark and Share
report post as inappropriate

Margriet Anne O'Regan wrote on May. 29, 2014 @ 06:53 GMT
Hello Allan

You've picked an aspect of the problem from which most steer away.

And handled it very well in my opinion.

I believe that one of the many problems compounding our judgements about, well, everything is that we don't have a a rigorously established adaptive profile for our species, or more simply, what's 'normal' for us.

As I agree with you that our 'normal' numbers are only a fraction of what they are now (& likely soon to be) this particular agreement between us only inspired me to respect your essay even more.

Thank you.

As I have figured out what I consider to be 'our own human norm' as drawn from evolutionary first principles together with the raw data all around us (which species' specific adapted profile includes our 'normal' means of population control - which 'control' has a lot to do with women's position in society, surprise! surprise !) I would value you reading & rating my essay which stands second in the 'submissions date' time line.


Margriet Anne O'Regan

Bookmark and Share
report post as inappropriate
Don J Chisholm replied on May. 30, 2014 @ 01:45 GMT
Alan, it is great to see a focus on one of the large invisible elephants sharing our living room. It goes unmentioned so often. The issue is also addressed in my essay by suggesting we shift to socioeconomic system that benefits both individuals and their community when birth rates are limited.

Population reduction is an essential issue. I’ve given a high score on my assessment.

Don Chisholm

Bookmark and Share
report post as inappropriate

Login or create account to post reply or comment.

Please enter your e-mail address:
Note: Joining the FQXi mailing list does not give you a login account or constitute membership in the organization.