My wife and I lived in a 430 square foot apartment with a baby. It was tolerable, but could have been very reasonable if the space wasn't so poorly utilized (the apartment was mostly bathroom and kitchen). We now live in 1,300 square feet with a baby and my mother, and we could easily shave 200-300 square feet off that if we didn't have unnecessarily large bathrooms and bedrooms.

Houses these days are unnecessarily large. My parents live in 6,500 square feet, and they're empty nesters! I guess that space makes a lot more sense be because they live in a suburban hellhole where there are no public spaces and every excursion outside is a half-hour car trip, one way.

There are many, many, many people producing children at well above replacement levels, and we are already well above the carrying capacity of our environment. I have no personal guilt at choosing not to have children.

Actually most advanced societies are not producing enough children to keep the population stable.

But they're importing enough immigrants to more than make up the difference.

Which is a very good thing.

Is it? Advanced society's dying off isn't something people usual celebrate.

Nobody said dying off, but it's a well-understood fact that humanity is growing at an unsustainable rate.

Good. There are too many people as it is. Running the birthrate at below replacement levels for a few generations is the only humane way to address that.

We're not well above carrying capacity for the environment, seeing as how mortality rates are going down and not up.

We're probably above sustainable carrying capacity. One of the great race conditions humanity faces is whether the bulk of the world will develop to a high enough standard of living for birth rates and hence population to drop before we run out of the natural resources we need to feed our current population.

>Inevitably you will need to have a partner and say, four children, for the human race to survive.

No, you personally won't. Plenty of people go their entire life without raising children and yet the human race continues to grow.

And there's nothing stopping you from raising a family in a small space. My family spent 6 months in a ~700 sq ft apartment in Chicago when I was growing up.

Even assuming that people started having four children "for the human race to survive" (a wacky thought in itself) what would prevent a family from having a compound of two or three tiny homes? At some point you would need so many tiny homes you wouldn't have much cost savings. But seems totally doable to have pair of homes or trio of homes, with, e.g., kids sleeping in one and parents in another, connected by common deck/porch.

people have a lot of kids in tiny houses all over the world.

Most people who choose to live this way in highly-efficient areas are +3 standard deviations away from the mean when it comes to wealth, which is also highly correlated with lack of progeny. So I wouldn't be worried about that.