[polarix]

I see the number of children a couple has as a vote on how many people should exist on earth. If you have 0 or 1 child as a couple, you are voting that there should be fewer people. If you have 2 children, you're voting that there should be about the same number of people. If you have more than 2 children as a couple, you're voting that there should be more people on earth.

With that context, I can clearly see why nobody in a city would want to have more than 2 children.

[pesfandiar]

You're grossly overestimating how much an average person cares about anything outside of their family. The decision to have one or more children depends on many other factors (parents' character, their economic status, social safety, ...) before it even gets to any idealistic activism.

[HumanDrivenDev]

So much this. Altruistic, considerate people who hem and haw over how their decisions effect others grossly over estimate other human beings. Take a walk along the side of a high speed road and look at all the garbage thrown there. People don't give a shit.

[dionidium]

This entirely misses the point, which is that most people -- yes, even altruistic, considerate ones -- don't think of their decision to have kids as politics.

[greglindahl]

Wait, so I should not worry about my personal ethics, but should only consider how shitty everyone else is? I don't think ethics works that way.

[HumanDrivenDev]

I never advised anyone to do anything. I just described some things I've noticed.

[greglindahl]

Ah. I'm having a hard time understanding what you mean, then, thanks for attempting to clarify, but I'm still completely confused.

Altruistic people are generally altruistic because they want to be altruistic for their own personal pleasure, not because they expect anyone else to be like them. So how does "grossly over estimate other human beings" come into play? If anything, most altruistic people underestimate other human beings, due to exactly the thing you mention... which are things that everyone has already noticed.

[HumanDrivenDev]

My altruism was eroded by life experience. I can't quite bring myself to actively screw others over, but I'm definitely not the 'good person' I once was.

Maybe true altruists are more resilient - but they're also much more susceptible to abuse.

[Fnoord]

When I was in California some good 12 years ago littering was $1000 fine as the signs said. And yes, I saw cops on the road. And no, I saw no garbage on the sides.

[greglindahl]

As someone with 0 children, I disagree with you. I'm voting that I personally don't want to raise children, and think that people who don't want to have children should not have them. My brother and sister like raising children, and have 3 each. Doesn't that affinity play a large role in people's choices?

[codingdave]

Are you under the impression that all families exactly hit their target number of children? Some people cannot have any children, but desperately want them. Some have one or two, but want more. Some people... well, not everything is planned. I know a woman who wanted one more child, and had triplets. And that isn't even getting into people who foster and adopt children.

In short, while I can see the logic in your stance... it has little bearing on the reality of creating a family.

[learc83]

Beyond that fact that the Earth's future population isn't the number one factor in the decision for most couples, 2 children is still below the replacement rate.

[robocat]

Strangely enough 2 is not the replacement rate. One birth per death is the replacement rate.

The world population can be increased by everyone having children earlier, or dieing later.

Puzzle: Every couple in Binary Town has twins (boy and girl) at age 32. Then half the population stops reproducing, but the other half change to reproducing at age 16. What happens to the population?

[Nasrudith]

Replacement rate depends on the death rate to be precise. If humanity had stuck with three children per couple at most throughout its entire history it would almost certainly be extinct.

2 is only the replacement rate for 'literally immortal up until a certain date' - morbidly with a corresponding high death rate the number could be 'greater than biologically the theoretical biological limits'.

Binary town's birth rate would go down initially due to the loss of participation reducing the reproducing generation by half but the time between generations being cut by half would mean an effective doubling of the per person rate. Without knowing their rate of death we can't know what happens to their true population over time and it goes without saying that the assumptions will break if their reproductive strategies change yet again.

[TangoTrotFox]

This is the wrong way of looking at things. 2 is always the replacement rate except in the case of an immortal population. You're not considering that you reach an equilibrium between deaths and births after one generational cycle. Imagine for simplicity that everybody gives birth at 1 and dies at 4. Let's look at when people have two children, starting with a genesis population of 10.

----------------

Year 1:

age 1 = 10

births = 10

deaths = 0

----------------

Year 2:

age 1 = 10

age 2 = 10

births = 10

deaths = 0

----------------

Year 3:

age 1 = 10

age 2 = 10

age 3 = 10

births = 10

deaths = 0

----------------

Year 4:

age 1 = 10

age 2 = 10

age 3 = 10

age 4 = 10

births = 10

deaths = 10

----------------

Year 5:

age 1 = 10

age 2 = 10

age 3 = 10

age 4 = 10

births = 10

deaths = 10

----------------

Etc. The only way to see a longterm increase in population is with a birth rate > 2, and similarly the only way to see a longterm decline is a birth rate of < 2. 'Longterm' in this case meaning just one generation, at which point the equilibrium kicks in. Of course not everybody dies at the same time, but the effect is identical when you look at an average with some distribution - which is what we have.

However, this also makes the assumption that everybody makes it to the age of fertility and that everybody is fertile. Both assumptions are incorrect so, in reality, the equilibrium point for population stability is even greater than 2. In reality we would expect to see a decline in population if each couple had exactly two children.

[robocat]

Our lovely residents of Binary Town keep their average birth rate at 2 through enlightened and fair methods.

Then Professor Gemini discovers a cure for cancer, which doubles their lifespan.

Unfortunately very soon they are having an unexpected housing shortage.

How did that happen?

[TangoTrotFox]

Sure if you create an absurd example of suddenly doubling every single person's life expectancy you can start to see some impact from changes in such, but in reality this does not happen. Life expectancy changes extremely slowly, and it also goes in both directions on a worldwide scale further mitigating any effect on population levels.

It's like Big O in a way. Adding some stuff to O(1) doesn't really matter compared to something that's O(n^2) except when start adding some really really unreasonably huge things, though even there n^2 tends to catch up really fast. In either case it's not a practical issue in code or population.

[crooked-v]

You're completely overlooking people who would want more children but don't feel they could afford them.

[Robotbeat]

...yup. This is probably most of my generation in their early to mid 20s, which is biologically the best time. Even if they can have one or two, they’re often busy with a degree or trying to eatablish themselves professionally. To get healthcare coverage (which is the responsible thing to do with children), you kind of have to be poor (to qualify for support) or be very successful.

[greglindahl]

Getting healthcare depends on where you live, not just how how successful you are. I live in California, and even before Obamacare, I could already buy healthcare for a family without being "very successful". Most Europeans are probably scratching their heads at the entire concept that you introduced. And yes, that's a part of the reason I no longer live in South Carolina, which doesn't have Obamacare.

[kaycebasques]

That seems implicitly related to reducing population. E.g. I’ve heard that hunter-gatherers adjusted their populations depending on whether there was lean or bountiful food. What you’re mentioning seems to be the modern equivalent of that.

[phamilton]

> hunter-gatherers adjusted their populations depending on whether there was lean or bountiful food

I almost feel like that's self regulating. Scarcity of food results in malnourishment which if it doesn't kill anyone directly, will result in other sickness being more likely to kill people. Same with children surviving to adulthood.

[zasz]

It is, but some foraging societies used infanticide as well.

[fjsolwmv]

The number of people who are poor enough to choose to have fewwer kids, yet rich enough to maintain effective birth control, is a narrow sliver.

[Robotbeat]

Disagree. There’s so many people who cannot have biological children (for many reasons), so practically speaking a large percentage of those who can should have at least 3 or the population will decline.

[squarefoot]

Many of us, including the planet under our feet, don't see it as a problem.

https://www.populationmatters.org/wp-content/uploads/2018/03...

I don't think there was anyone in the 1960s screaming "oh crap... there's only 3 billions of us around here!". We're so used to think the now and here as normal conditions that we lose focus on the global trend which is absolutely disastrous.

[wool_gather]

It is a bit of a problem inasmuch as core values/ideas are often (not always, but often) transmitted by family connections. So paradoxically, concern for the planet leading you to not have children could reduce the relative number of people who share your concern.

Then again, there are other memes that lead not just to lack of reproduction, but directly to the death of the memeholder, so maybe it's not such a big deal. Still, just another thing to wonder/worry about.

[squarefoot]

Interesting point. Also culture could play a role here; it is possible that concerns about overpopulation are primarily shared among those people who are less responsible for it (living in "western" industrialized countries), so that by having less children they rather reduce the number of people sensitive to the problem than limiting overpopulation in significant figures.

[TangoTrotFox]

It's not just concern on this one issue. In general fertility tends to be strongly correlated with low education, low income, and high religiosity. This is true both inter and intra nationally. Think about what this means. Currently each day about 353,000 babies are born. As people who are educated, wealthy, and secular choose to not reproduce to the point of replacement - it is in a way condemning the demographics of those 353,000 children.

I tend to be aligned with you in the view that Earth having fewer people would is not a problem, but at the same time demographic collapse is very much a real issue. As the only people considering these things would likely be the people that ideally should be pumping out babies left and right if we want to create a better planet not only for humanity but even for the planet itself.

And as an aside this is of course not to say that no great things will come of those 353,000 born into less than desirable situations. But on average people's outcomes tend to be very strongly linked to those of their parents.

[wool_gather]

Well pointed; it's a thing that needs to be considered, but it's a tough position to take and hold. It's an unfortunately short hop from a fact-based "we need to figure out how to create better outcomes" to a really nasty sort of proto-eugenics that says something like "poor people shouldn't be allowed to breed". And proponents of the latter may act like (short-term) allies of the former.

[greglindahl]

"Limits to Growth" was from 1972, but Mathus' idea dates back to 1798, and he was certainly not the first to bring up the concept.

[tcbawo]

Malthus was probably correct without the invention of fertilizer. Hopefully technology like seaweed and vertical farms come to our rescue!

[Nasrudith]

Even without that his ideas were a daft excuse for starving the poor because it was the 'convenient' thing to do for the people in power because feeding the poor actually working the farms would cut into their short term profits. Look at the Irish Potato Famine. The disporia emigrated and helped drive industrial booms and some like the Carnagies became wealthy. This points to the policies not only being a humanitarian catastrophe but a vast squandering of resources. The events came to a head after the actual man's death but he still bears some responsibility and his followers the remainder.

Meanwhile Ireland is /still/ down in population compared to its peak. Given the evidence I can't help but judge Malthus and his ideals as both stupid and evil. I suppose that describes a lot of downward historical trajectories actually - people in power do something selfish for short term gain because they don't see or care of the costs, ruin the lives of everyone around them a thousandfold and eventually themselves before permanently damaging their institutions.

On another note food is so far from being the limiting or driving factor for population it isn't funny. What truly drives reproduction are the actual incentives - even back in ancient times farmers had explosively sized families while the urbanized tended to have more modest sized ones simply because of other resources constraining. Neither human labor nor water, nor arable land are in scarce globally although all three are mismanaged some.

[danieltillett]

No it is natural selection in action. Those that have children are of the future, those that don't are of the past.

There is a huge shortage of smart people on the planet to solve the many problems that exist. The best way we know to create more smart people is to encourage smart people to have more children. Unfortunately we seem especially good as a society at identifying smart people and discouraging them from having children.

[smt88]

Children per couple goes down as quality of life goes up. All developed countries see birthrates decrease. No one is actively discouraging smart people from reproducing -- they're just better off and don't need children as a safety net for retirement, and they can access good birth control.

The idea that smart people are only produced by other smart people is nonsense. Genes regress to the mean, so most smart people won't have mostly smart children. And intelligence is significantly affected by nurture, not just nature.

And beyond all that, smart people aren't the end-all, be-all of humanity. They make useful things, but are of course capable of great evil (or mental illness or any other issue that limits their contribution to society).

[danieltillett]

Yes nobody is activily discouraging smart people directly from having children (this is why it natural and not artificial selection), but it is still selection.

Where did I say smart people having children is the only way to create smart people or that intelligence is only affected by genes? Please read what I actually wrote, not what you think I wrote.

Smart people are the people that have the ability to solve the hard problems we face. We have a huge number of very hard problems in the world and not enough smart people to solve them all. We need more smart people.

[smt88]

You didn't say it was the only way. You said:

> "The best way we know to create more smart people is to encourage smart people to have more children"

...which is also unsupported by current intelligence research and still relevant to my counterargument.

[danieltillett]

Actually we know that intelligence is mostly genetic (especially at the high end), but even if it isn’t, the family environment provided by (most) intelligent parents is very conducive to raising intelligent children.

It doesn’t matter the means (environment or genetic) as both will contribute to smart parents raising smart children (provided they have children).

[smt88]

Socioeconomic status is far, far more important than genes[1]. If you want more smart people, give people more money.

1. https://www.psychologytoday.com/us/blog/under-the-influence/...

[tcbawo]

I don't know if we need more smart parents or rather caring/nurturing families. You don't have to be smart, but children of dysfunctional families are at a disadvantage for breaking the cycle.

[SamReidHughes]

> The idea that smart people are only produced by other smart people is nonsense.

Don't be ridiculous. If dumb people have more kids than smart people, the next generation will be dumber. Intelligence wouldn't have evolved if this wasn't true.

[dabbledash]

I’m not sure that is the best way we know.

There are already many smart people who aren’t helping to solve those problems because they haven’t received the necessary education. I’d go so far as to say we’re probably missing out on the potential contributions of most smart people now.

What we need to do is figure out a way to radically increase access to education worldwide.

[danieltillett]

Do you know of a better way to create more smart people because I don't. It is not simply education or else the rich would never have dumb children.

Yes we are wasting the potential of many smart people in the world by not giving them the education they need, but we are pretty good at it across most of the world already and getting better all the time. A poor very smart kid no matter where she is born will likely be identified and given an education. I personally know many smart people born in total poverty in very poor countries who have reached a very high level of education.

[dabbledash]

I think the fact that you know many educated, smart people from very poor countries doesn’t mean that most or all smart people in very poor countries get good educations. I was under the impression that there were many places still where large numbers of children, particularly girls, don’t complete a secondary education. (Open to being wrong about that though).

I’m definitely not against looking for ways to make knowledge work compatible with building a larger family.

I just don’t think increasing reproduction in the college educated is our best play for increasing the number of smart people working on hard problems.

[danieltillett]

Most people in rich countries don’t get a very good education, but most very smart people (even girls) born anywhere do get a chance. I do agree we could do better, but things are overall improving.

I don’t think arguing for encouraging smart people to have more children argues against improving the education of poor smart people. This is not a zero sum game.

[wool_gather]

It's not very clear what the connection is between your two paragraphs. In fact, they seem contradictory; why does natural selection lead to fewer smart people having children?

[danieltillett]

It is just a consequence of the human environment changing. Birth control and the modern education system disproportionally effect the number of children smart people have. The end result is the smarter you are the less children you will have all other factors being equal.

Another major factor contributing is children are very expensive and smart children are much more expensive to raise than the average child.

[watwut]

Smart children are not more expensive then average child. Competitive, ambitious parents and parents who want their children to be smart have additional expenses.

[danieltillett]

Yes they are (on average anyway). Their parents sacrifice greater income to have them and even their education is more expensive in that living in areas with good schools cost more.

Of course you are right that provided identical environments smart and average children cost the same, but since smart parents tend to earn more, smart children cost more.

[watwut]

Parents who choose good schools choose them regardless of whether kids are smart. High income parents don't want the children in bad schools even if kids are not smart (whether it means stupid or just normal).

Non-smart child of smart parent costs even more - on tutors and such to raise the kid.

That is not smart children costs more. That is ambitious/smart parents spend more on children. The cost of smart child here is merely function of correlation with parent.

[greglindahl]

You should check out the history of eugenics, it sounds like you'd be interested in those concepts. Do keep in mind that almost everyone is offended by them, however.

[danieltillett]

Eugenics has two strands (negative and positive). Many people are offended by the negative (stopping the "undesirable" from having children), but I haven't met too many people who are offended by the "desirable" choosing to have more children.

This is all tangential to my post.

[greglindahl]

It's not tangential to me, and yes, I'm totally offended by both strands. I used to date the author of the "Darwin Awards" website and books, and I've spent a lot of time interacting with the general public about these concepts.

[danieltillett]

Why are you offended by people choosing to have children? Seems rather strange to me, but I guess the world is a big place.

[greglindahl]

I am not. I’m offended by eugenics, no matter how you phrase it. Having children is not eugenics.

[handbanana]

Can you explain/expand on why you think it’s natural selection?

[danieltillett]

The number of children you have is selection (in an evolutionary sense) and because it is not a trait being selected for directly by anyone (we are not trying to breed people that want or don't children), the selection is being done by nature.

The environment of humans has radically changed and we are undergoing very strong selection and adaption to this new environment. In the past the number of children you had survive to adulthood was tied to the amount of food you could bring in (as with most animals). In the new human environment the number of children you have is a consequence of how resistant you are to the cultural meme that children are undesirable.

[phamilton]

I think he meant more that natural selection is essentially summarized as how many children various groups have. And for some weird reason, natural selection is biasing away from "smart people".

[dabbledash]

I don’t think it’s too hard to figure out. Natural selection disfavors a strategy that requires significant investment in non-reproductive activity (education, career ladder-climbing) during prime reproductive years.

[greglindahl]

Natural selection works on genes, not individuals. How do my career choices affect my brother's and sister's children?

[danieltillett]

The selection part works on individuals, what changes from selection is the frequency of alleles in the population. By not having children the alleles you carry will become rarer in the population of the next generation (all things being equal).

[Scarblac]

Not just how many children the groups have, but also how many of those make it to healthy adulthood to reproduce themselves, etc.

"Smart people" have fewer children but they're more likely to be successful.

[Fnoord]

How about we educate those who are not smart to become smarter?

[Apocryphon]

You could also adopt one or more children. How does that affect this calculus?

[notadoc]

Interesting way to look at it, I have never met anyone with that particular way of thinking about children.

Most people I know made decisions about having children in terms of resources. Mainly, about available time and/or money.

[kaycebasques]

I don’t see these two ideas as at odds with each other. Maybe people aren’t explicitly calculating that they should reduce the population, but deciding not to have children because of lack of resources seems like a subconscious vote to reduce the population, in my view.

[Fnoord]

There's another option besides "not having children": "having less children."

[kaycebasques]

A lot of responses disagreeing with this idea. I’ll lend some balance and mention that I’ve had the exact same reasoning in my own plans for the future. I won’t pretend to argue that I’m normal or abnormal, though. Haven’t done any research on the topic.

[greglindahl]

I can totally see that you are voting on that issue with your choice, however, does that mean that everyone else is doing the same?

[kaycebasques]

Like I said, I’m not claiming to be normal or abnormal, meaning I don’t know if it extends to others. You’re not providing evidence to the contrary, either, so you’re word is as good as mine.

[greglindahl]

"This idea" is that everyone is voting, not that you personally were voting, or that I personally was voting.

If you instead wanted to provide yourself as an anecdote, that's different.

Sorry that I was unclear. Personal anecdotes are quite different from claiming something is a global rule. I was just trying to double-check that you were giving an anecdote.

[kaycebasques]

Ah, got it. Yes, I was just countering the anecdotes against this idea with my own anecdote for it.

Thanks for clearing up the confusion.

[greglindahl]

Excellent. Thanks. I totally agree that I have a few friends who are like you: they're very concerned about the planet and that affects their childbearing plans. Me, that affects what I eat, but it didn't change my childbearing plans.

[dsnuh]

How many votes have you cast?