Skip to Content

John B. Calhoun and the Future of Wealth

One of the most important studies ever conducted on human interactions with money, wealth, and retirement was undertaken in 1968 and it involved mice.

John B. Calhoun, an ethologist and behavioral researcher, had a long history of studying rodents in differing environments and recording the rodent’s behaviors and interactions.

Much of Calhoun’s earlier work involved Norway rats. But in July of 1968, Calhoun began a study using mice. This research has been debated ever since. A common debate is comparing the mice to humans and population. However, what most never noticed is that the mouse experiment had nothing to do with population and everything to do with wealth and retirement.

John B. Calhoun at the baby show of his first grandchild.
John B. Calhoun at the baby show of his first grandchild.

The Mice Experiment

In the mice experiment Calhoun placed four breeding pairs of mice into a setup that can only be explained as a mouse Nirvana. There was room to run and play. There were tunnels for easy access to other rooms and areas within the habitat. Ample nesting areas, water dispensers and food hoppers were throughout the habitat.

The mice lacked for nothing. They had no predators. They had food, water, and other mice to play with. Life was good in mouse heaven.

The only issue the mice would eventually face was space. As their population grew the habitat would become more crowded. This is what Calhoun sought to research, but it evolved different from expectations.

As expected, the four breeding pairs enjoyed their carefree environment, doubling their numbers every 55 days.

By day 315 the mice increased their numbers to 615. This population was far short of the estimated carrying capacity of 3,840 for the habitat. Still, after day 315, the population growth slowed markedly. The mouse population now doubled every 145 days.

Then things went south.

From day 315 onward social structures strained and eventually broke. Attacks on the young were common. Some young mice were injured, some kicked out of the nest before weaning was complete. Males became aggressive toward females. Homosexual behavior increased. Dominant males struggled to defend their territory and females. Non-dominant mice increasingly attacked each other.

The rooms in the habitat were designed to hold 15 mice comfortably. Yet, in these later days of the experiment, as many as 50 mice would huddle in a room when empty rooms were next door. This self-induced compacting of mouse flesh potentially caused more animosity and fighting.

Some males withdrew and found a solitary place to live in the structure. Their only activities being eating, drinking, sleeping, and grooming. These recluse mice didn’t have scars like the other male mice and the grooming kept their coats smooth. Calhoun called these male mice the “beautiful ones” due to the lack of scars.

Yet, the collapse of mouse society must have been more than the physical environment. Why some mice fought and some found a quiet corner to live out their life is unknown. We do know the “beautiful ones” while looking healthy, never took an interest in procreation.

From day 615 on the fabric of mouse society fractured. Mouse population in Universe 25, the name given to the experiment since it was the 25th undertaken by Calhoun using rodents, reached 2,200 in the 19th month. Less than 5 years from the start of the experiment, all the mice were dead.

What is most interesting is that as the population fell things never returned to normal. The declining population did not reach a point where healthy behavior returned. The early lower population with a healthy mouse society on the way up did not re-engage on the way down.

And as much as the debate of Universe 25 has been on population, that was never the real issue. The mouse heaven came nowhere close to the maximum population the environment could sustain. There had to be another issue. And the real big question: Does this teach us something about people and humanity? Could we suffer the same fate?

Universe 25 in the Modern Human World

Calhoun, and many after him, have come to varying conclusions about Universe 25. Generally, the discussion has focused on population and its possible correlation with humanity. But that doesn’t make sense!

We have seen squalor and overcrowded cities for centuries without anything near what like happened in Universe 25.

Crowded population centers have not suffered the breakdown of society the way it did in the so-called mouse heaven. Yes, there are many instances of social breakdown among humans. And you need a certain number of humans to have a riot or other social unrest. (One guy having a solo riot in the countryside is not a social breakdown. Maybe a personal breakdown, but not a social breakdown.)

Still, the human population keeps climbing.

But something is different now. Many of the anti-social behaviors of the mice are showing up in humans.

There is no way to compare an exact mouse-to-human interaction. For example, the mice may have developed a learned behavior between crowding and food. This behavioral sink didn’t dissipate when the mouse population declined to less crowded conditions, some speculate.

And while a near mouse heaven was created, the same is not possible with the entire human population. People are far more complex than mice.

John B. Calhoun in Universe 25, the mice experiment.
John B. Calhoun in Universe 25, the mice experiment.

Breakdown of Human Society

As smart as people think they are, we are still mammals, filled with all the fears and desires mammals have.

The question then is: Will increasing population lead to societal breakdown as it did in Universe 25?

The first cities were founded around 9,500 years ago. People, by choice, decided to live together in larger groups. Cities offer advantages in a salvage world. It also allows for specialization. Universe 25 would never see mice organizing their population growth while humans have done just that for a long time.

Population puts stress on resources, causing wars or at least border skirmishes. The steady drumbeat of technology has allowed for ever increasing conglomerations of people in small geographic areas. The same technology reduced the need for war over resources. (The need was not eliminated, however.) Reference the work of Steven Pinker for a more complete view of how violence has declined.

People thrive in population centers. Even with urban sprawl and the blight of some modern cities and those of the past, the breakdown of society was and is managed and addressed. We see nothing like Universe 25 or any of the Calhoun experiments in humanity as it applies to population.

But humanity is having a breakdown in society like never before and it does affect population.

Societal breakdown is more than social disorder. It is often very personal and painful.
Societal breakdown is more than social disorder. It is often very personal and painful.

First, a discussion of the breakdown.

A disproportionate number of young people are no longer engaged as in the past.

We might be tempted to complain that young people are lazy today when we hear around 60% of Americans were employed in 2022. While the percentage of working-age people working is down, it isn’t down that much when we account for the number of children and people at retirement age and older.

So that isn’t a breakdown in society.

Young people are more likely than ever to forego romantic relationships and even more inclined to forego building a family.

Like the experiment with mice, the societal breakdown is crowding people together, even when unnecessary. Rural life is desired by many, yet in the end most opt for an urban lifestyle.

As with the mice, people have a lower desire for procreation. Worse, there seems to be a massive decline in desire for intimate and interpersonal relationships.

Homosexual behavior increased in Universe 25. We see something similar in many countries around the world, especially in the West.

Note that homosexuality is not some modern societal curse. Homosexuality has been around since the beginning of time and is not the problem. The issue is that more people identify as something other than male or female. And more are coming out as homosexual. Either these are people at the borderline or more people are open to exploring the newly acceptable avenues. Still, there is an interesting correlation between Universe 25 and modern society.

What about the “beautiful ones” from Universe 25? We have always had the rich and their excesses. There are more high net worth people than ever before, thanks to technology. And the Elon Musk’s of the world can become very wealthy even compared to the wealthiest of the past.

The uber-rich anti-social behavior is not completely new either. These issues were always with us. But even with more wealthy people than ever, why the radical change in demographics?

Men have been crowded out. Or at least many feel that way. There is actually a class of men called MGTOWs (Men Going Their Own Way) and incels, which stands for “involuntary celibates.”

There is affirmative action to protect every group, except men. Colleges and businesses must have inclusion. The best are sometimes not hired if they happen to be a white male. Again, this from the viewpoint of some men.

There are financial conferences for women. Can you imagine the outcry if there were financial or business conferences designed for men only?

There are reasons for the changes that have taken place over the past century. Women and minorities were excluded and harmed by “traditional” behavior. Have we gone too far? Have we created a problem with difficult solutions people are not currently willing to address?

All this new world order has too many men checking out. We get MGTOWs; men who have disengaged from most social interactions outside work.

These disenfranchised men are unwilling to live under the new rules. They crawl away to some hidden place, their apartment, and live a secluded life of video games and social media. At least they can strike out at enemies on social media without fear of societal reprisals, sometimes. This echoes the beautiful ones in Universe 25.

Before we beat up on men too much, let’s talk about females.

This author has two daughters, both in their 20s. One knocking on the door of 30! Neither has a boyfriend (or any significant other) or has an interest in one. This is not the world I grew up in.

We can blame the men for feeling the way they do, telling them to man up. But women have also withdrawn!

Just like the mother mice in Universe 25, the desire for children has diminished significantly.

Men are often unsatisfied today. So are women! “Where are are the good women?” the men cry! “Where are all the honorable men?” the women lament!

Like the mice in Universe 25, the entire population is infected with a disease. Men and women, among humans, can blame each other. But the problem is much deeper.

We can force law and order. But force only goes so far. True order comes from voluntary compliance.
We can force law and order. But force only goes so far. True order comes from voluntary compliance.

Now, the consequences.

We must review the consequences before the real problem is discussed and the only possible solution offered.

The “checking out” of men and women in nearly all societies around the world has lead to serious consequences. So far we dodged the bullet. But only because it takes time for the poison to kill.

What killed the entire population of mice to the last one was a loss of desire to carry on the species. We may not think of it in those terms, but that is exactly what having children is about. No children and tomorrow will still come. Only, your species, humans, will not be there.

Data from the World Bank is damning.

The fertility rate among women worldwide was 2.3 in 2021, the latest year data is available. The replacement rate required to maintain a steady population is 2.1. This means 2.1 children are required on average among all women to maintain the current population. The extra .1 covers children that die before reaching sexual maturity.

The fertility rate in China is 1.2. 1.2! Even removing restrictions on the number of children women in China could have had only a modest blip in the statistics. The message is clear. Chinese women don’t want to have children and if they do they want only one child.

The fertility rate in most of Western Europe in below 2.1. Russia is at 1.5. Japan 1.3.

The U.S. fertility rate is 1.7.

China is set to lose two-thirds of its population by century end. China and the U.S. will have a similar population in 70-80 years. The only reason why the U.S. will maintain its population with such a low fertility rate is immigration.

The population bust is coming and it will be painful, mostly due to the rapidity of the population decline.

Darrell Bricker and John Ibbitson have an excellent book on the topic, Empty Planet. It is worth your time to read the book.

Woman sharing a carrot with a horse.
Only when we share can we find meaning in our life. It also gives meaning to the one we share with.

True Problem and Solution

It is vital we stop blaming others for the problem. Yes, men and women feel confused and empty, looking for meaningful relationships without a desire to engage. The goal must be to bring back the desire for intimate relationships.

John B. Calhoun taught us a lot with his experiments. The overload of information, coupled with the misguided biases, has thrown us off the track of a meaningful life.

It was never about population. It is the fear of a population bust that may have triggered the unconscious response in America and other nations. The misguided thought of taking away the reproductive rights of women was a bad idea before it was uttered.

As with China, it will not work. For any meaningful change to happen, people must want to change. If men hide away in some upper room eating, drinking, playing video games, and roaming social media, the problem will not resolve.

Neither men nor women will engage without addressing the “real problem.”

The real problem alludes us because it crept up slowly.

Technology requires fewer of us to work physical jobs. A mere 1.3% of U.S. employment is direct on-farm employment. A few generations ago over half of the population worked on farms.

Technology has made factory jobs less dangerous while productivity soared. Technology eliminated the need for so many workers on the factory floor.

Technology has allowed everyone to live a better life and have a better lifestyle all at the same time.

We always had hyper-savers and investors able to leave gainful employment early in life. The difference now is that it is easier to do so and many have chosen just that.

There is even a community dedicated to early retirement called Financial Independence, Early Retirement (FIRE). This is not an outlier! A significant percentage of working age people have elected to check out.

Those not electing are often working less.

Regardless, we all have more no matter what your work ethic. Technology has allowed us to provide more goods and services than ever before that are affordable.

We all live in paradise, Nirvana, heaven. Just like Universe 25; just like the mice. We have no unmet needs. We have wants, sure. And we feel empty. In a world of 8 billion people, many feel incredibly alone.

Our lives have lost meaning! That is the “real problem!” We have no purpose. We have everything a mouse, ah, human could want. Without any challenges, without purpose, without a reason, how can one go on? Why care? Why have an intimate relationship? Start a family?

The “real problem” is that we lost purpose in life.

The solution is simple, yet incredibly hard to start.

Zig Ziglar said, “You can have anything you want as long as you help enough other people get what they want.”

What if you already have everything? Truth is, you have everything you need and more, save one: purpose.

The Viktor Frankl wrote, “The meaning of life is to help others find meaning in theirs.”

That is the answer, the solution. Most people don’t need more stuff. Some might have basic needs. People in a homeless shelter, for example. But most of us have enough to live a happy life. Now we need to take the last step so our life is worth living.

It sounds so simple, just help others. But it is so hard because it requires you to open up and let someone else in. They may hurt you; take advantage of you. Yet, without the risk, there can be no hope.

If we do not get the message we may in the end suffer the same fate as Universe 25. As population declines we may cocoon more and more until there is no one left.

Some say the world will end in fire, Some say in ice. I hold with those who favor fire. And would suffice.
—Robert Frost

The future of wealth? Well, wealth is much more than money or stuff.

While wealth comes from in here (pointing to heart) and here (pointing to head); it only has value when we give it away.

Could it be the solution to the Fermi Paradox (why don’t we hear from other civilizations in the universe) is that when a species reaches an advanced level of technology it eliminates the desire to live?

We must do better than that. Our world depends on it.

And the only way to save ourselves is to open to others. And to give.

It is the meaning of life. It is purpose. And our only hope.

Andy Ropeher

Tuesday 18th of June 2024

Good article. As a pensioner who chose to be FIRE'd. I stumbled across Universe 25 whilst looking for reasons on population decline and the effect on pensions! I wish I hadn't as now, unfortunately, every day I see or hear an article which reinforces the mind-bending fact that this is happening. Just a skim over the current Japanese society makes me wonder if that isn't a Universe 25 experiment being run in the real world. (Perhaps by Mice getting their own back! Ref Douglas Adams.)

Recently there was a school in the UK that asked some of their mid-teens to give up their phones for two weeks. The BBC reported on it and after 2 days one boy was so distraught to be away from social media that they had to give him his phone back. The BBC interviewed a woman who I assume was his mother, (but I'm not sure about that,) but it was her comment that clicked for me..."he is addicted to social media, and it has become his prison."

Is social media the human equivalent of Mouse Utopia?

I too have two children of about 30. One boy and one girl. The boy has had some girlfriends, but has told me that they all became toxic, and got out before making a lifetime mistake. My daughter is a left wing feminist and thinks all men are a disgrace. I blame her university course which was nearly all women training to become primary school teachers. She now has no interest in men, relationships or having her own children, (she loves other peoples though and would make a great mum.)

It looks like the modern world has lost it's soul.


Thursday 10th of August 2023

Very well written article! My family's cousins range in age from mid-20s to mid-50s. Everyone over 32 is married with at least one kid, but the 31 and under set (there are 6 of them) don't seem interested in marriage or kids. We can't figure it out, honestly. Most of us older cousins (I'm mid-40s) have pretty equal parenting and both parents work; my youngest married cousin is the only female not working right now.

Did your daughters read this article? I wonder what their perception of the situation is. My cousins tell their parents they're not ready or they're still looking, but I'm not sure if that's to get their parents off their backs or if they are being honest. I younger person's perspective would be useful here!

I've started talking to my older kids (high schoolers) about the importance of looking for a potential spouse in college, in the hopes that they will eventually each find someone! My oldest son has finally stopped saying that he doesn't want to get married, although he still says he doesn't like kids. We're working on it, lol.


Saturday 14th of October 2023

@Keith Taxguy, EA,

There is a biological drive, but the outcomes of the drive is minimized. Abortion. Contraceptives. P****graphy. In the past, kids were assets (e.g. helping on the family farm, taking care of aging parents). These days, kids are expenses. And the expenses are much higher than in the past. For many people, income have not kept up with expenses. You bought a house when you were in your 20's. How many people in their 20's these days are able to do that.

Overall, humans are self-centered animals. People will have kids if it benefits them and won't have kids if it won't benefit them.

If you want grandkids, you may have to specify that inheritance of your assets to daughters will only take place if they have at least 1 kid. Otherwise, the inheritance will go to spouse and then charity. Anyways, if your daughters are expecting to inherit your fortune, they may consider themselves wealthy and wealthy women are less likely to have kids out of wedlock and are less likely to marry.

Keith Taxguy, EA

Thursday 10th of August 2023

Vida, not only did my daughters read this article, I discussed the issue with them at length before writing it. My oldest daughter teaches at a local technical college. Her personal insight coupled with what she sees from students is eye opening for this accountant.

My daughter had no explanation. She just isn't interested in a relationship. She feels no compulsion in any direction, just complete apathy over the issue. Many of her students feel the same.

Like you, neither my daughters, nor I, have an explanation. What really gets me is that there is no procreative drive. I can understand not wanting to start a family, but no biological drive? It makes no sense to me and is the reason I found the mice experiment so compelling. Are we living out that experiment with some modifications or is this a true human population adjustment that ends up being healthy? Better minds than mine need to answer that.


Monday 7th of August 2023

Several thoughts in no particular order:

- For humans part of the issue has to be with age segregation. We are so rarely around people in a different stage of life from ourselves. If you are never around young children how are you going to get baby fever?

- The professionalization of everything breaks us apart. If everything could better be done by someone who's job it is to do it we don't offer our own poor efforts to one another. We will pay for a meal delivery instead of bringing a meal to someone in a challenging part of life. Instead of talking to a neighbor about a conflict we call the police. Rather than handing over some money to the person on the corner we insist they go through proper channels and donate to the local homeless shelter. Or instead of hiring the guy pushing his lawnmower around the neighborhood we opt for the licensed, bonded, and insured mower "just in case." We are so overly concerned with privacy and preference and liability, we care so much and are thus uncaring.

- I don't know if it is at root reason or rationalization but so many childless by choice folks seem to believe that humans are inherently bad for the planet. That we are some sort of parasite on the world and that it would be a better place without us. And looking at a lot of the climate change articles and manmade disasters its a reasonable conclusion to draw. Hopefully we will start getting more and more data and coverage of pre-European Americas and how humans shaped and cultivated the world around them while also allowing for diversity. Prioritizing mutual flourishing over efficiency. The doom and gloom over the world's future is also propagated by the culture war folks, why would people bring poor innocent children into a world that is so destitute and depraved? That'd be downright unethical.

- Would love to see more discussion on birthrates variance across socio-economic lines. It seems that the more money a couple makes the fewer children they are likely to have. What are the consequences of those who have the most resources available to them have the fewest children while the bottom rungs of society fill most of the population?

- If America's continued economic future depends on immigration then we better start acting like it. The current trickle of legal immigration is ridiculous. There are certain jobs in our economy that nearly always default to the new population and because we are allowing unaccompanied minors THEY are the ones filling those positions. We don't need 14 year olds in factories dying we need adults.


Friday 4th of August 2023

Rapid population decline is real. The average person isn't financially responsible enough to take care of themselves, let alone another human. Just look at how many individuals and families are living paycheck to paycheck.

The reason why I'm not worried is because I don't see a realistic situation where this planet lasts until the year 2100 or 2200. I just don't think the path we are on is sustainable. Earth is heating up at a dramatic level and will at some point become uninhabitable.


Thursday 3rd of August 2023

I never wanted kids because the idea of having to do nearly all the associated chores seemed like condemning myself to a life of drudgery, all work, hardly any fun for at least a couple decades. I was raised to work hard and pursue education (I did: college degree in econ, MBA, CFA charterholder) and had a well-established career before I got married. There was simply no realistic possibility of finding a straight man who would be willing to co-parent with me on a true 50-50 basis. I married a wonderful man who was ok with not having kids. I always wanted to be married because that seemed awesome (the first dozen years have been!) but to me, straight couples having kids always looked like a pretty raw deal for the moms.