[resonator]

I'm very uneasy about us collectively seeking longer lifespans. Earth is already supporting more people than is sustainable. Living longer robs someone else of an opportunity to live, or a shorter life. Over many generations we may be able to lower our birthrate to compensate, but I worry about happens in the meantime.

[JumpCrisscross]

> Over many generations we may be able to lower our birthrate to compensate

We’ve gone—globally—from 5.3 births per woman in 1963 to 2.3 in 2022 [1]. 2.1 is replacement [2]. In the rich world, where longevity treatments will first become available, it’s 1.6 [3]. (3.3 in 1960.)

There are arguments against longer lifespans. Population growth is not one of them.

[1] https://data.worldbank.org/indicator/SP.DYN.TFRT.IN

[2] https://pubmed.ncbi.nlm.nih.gov/15832599/

[3] https://fred.stlouisfed.org/series/SPDYNTFRTINOED

[resonator]

I don't argue for a second that our birthrate isn't dropping; it is. But we either haven't dropped it enough, or it's being offset by higher consumption. The overshoot day is now the 1st of August [1]. Until we push that back out to to a sustainable level, we haven't done enough.

To achieve that, I can only see a few classes of solution. We could reduce our per-capita consumption, our lifespan, or our number.

I'm assuming that the overshoot day is roughly correct. The details of exactly how much our birthrate has dropped or by how much our consumption has increased isn't important to know that there is a massive discrepancy between where we are and what is sustainable. Doing anything that increases that discrepancy is probably going to make it worse.

[1] https://overshoot.footprintnetwork.org/

[JumpCrisscross]

> We could reduce our per-capita consumption, our lifespan, or our number

What is your evidence for shorter lives promoting long-term thinking? Like, look at a map of life expectancy in America [1]. Is Mississippi the bastion of ecological awareness you’re looking for?

Number and per-capita impact are the important variables. Wealth reduces the former and exponentially increases the latter. Longevity reduces the former and linearly increases the latter. (Poverty and reduction in lifespan exponentially increase the former while linearly reducing the latter; you don’t worry about efficiency when you have a short, brutish life.)

[1] https://en.m.wikipedia.org/wiki/List_of_U.S._states_and_terr...

[resonator]

> What is your evidence for shorter lives promoting long-term thinking?

I'm looking at it in the other direction; that long-term thinking might result in shorter lives.

[JumpCrisscross]

> looking at it in the other direction; that long-term thinking might result in shorter lives

Based on what? Increasing lifespan reduces fertility [1]. This is empirically and theoretically grounded. Older populations shrink [2]. Your proposal, shortening lives, is one for boosting populations and consumption.

All that said, this debate is academic. If longevity treatment is possible, we will develop it, and the population can sort itself into those who live longer and those who don’t.

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3220400/

[2] https://www.nature.com/articles/s42949-021-00023-z

[cstrahan]

We'll be alright:

https://www.forbes.com/sites/michaelshellenberger/2019/07/29...

https://www.newscientist.com/article/mg22029445-000-admit-it...

What value do you get out of believing in Earth Overshoot Day? Does it provide real, actionable utility? Does such a belief instill good feelings?

If I had to guess: it tickles the reward pathways in your brain, connected to your survival instinct to be aware of possible threats, whether real or (as I would argue is the case here) imagined. I would doubt there's anything you plan to personally do about Earth Overshoot Day, and I doubt thinking about it instills positive feelings. It's doom porn.

[pedalpete]

What makes you think we're supporting more than is sustainable?

Though I don't think we desperately need to make more people, as some people think we do, I also don't think we need to restrict lifespan progression.

When I look at sustainability of the planet I consider 1) significant portions of the population are obese, and these numbers continue to trend higher. This suggests that we have an abundance of calories available to support more people. We have too much food.

2) water, and particularly fresh water is probably the most restrictive element we require. But I don't think we are restricted by a lack of water, we are restricted by a lack of clean water in the right geographic regions, and of course, the damage that we have caused to the supply. However, we are generating methods of creating fresh water.

3) energy may be the last resource, and particularly that major portions of our current energy needs are provided by damaging and non-sustainable methods. This doesn't mean we need to pause longevity potential, we need to find clean methods of producing energy, which is, and has been in development for a long time.

Is there something else big that I'm missing here?

[cstrahan]

> Earth is already supporting more people than is sustainable.

By what metric? If it's a matter of available land, there's plenty to go around: open Google Maps, turn on satellite imagery, center the map on Arizona, USA and zoom in. Absolutely nothing but interstate roads and bushes. No buildings, no people, no nothing.

"There are over 11 million blocks in the U.S., and 47 percent of them are uninhabited."

https://www.fastcompany.com/3029826/mapping-all-the-places-i...

Our large, metropolitan cities may be more crowded than sustainable, but Earth != NYC.

[shrimp_emoji]

> Over many generations we may be able to lower our birthrate to compensate

Already on it, boss!