Aging exists because the human body is optimized to survive and reproduce in a resource constrained environment with many threats. Our predecessors eked out just enough calories to survive to the age of 15, when we could begin reproducing. Any traits that made it more likely for us to survive until that point, even if those traits resulted in damage that would eventually accumulate and wear us down after our reproductive window, was selected for. We are all basically running the biological equivalent of overclocked CPUs without investing in proper cooling.

We no longer exist in a resource constrained environment and have access to massive amounts of energy from the sun which makes entropy a negligible concern. There is no good reason to not at least try to prevent or reverse senescence.

I don't think "live to 15, have kids, and die" makes sense as a model for humans, even if you're modeling them solely as child generating machines.

Humans are a pretty damn care-dependent species. They're not going to defend or feed themselves without years of support, so if they aren't surviving en masse into their 30s and 40s, the next generation is probably going to have a severe die-out.

Beyond that there's probably ongoing marginal benefits to species fitness with longer lifespans. If you can keep a few generations in circulation at once, you probably have greater resilience to things like disease outbreaks (the 50-year-old cohort might have some past related immunity to a disease that rampages the 20-year-olds).

This also completely ignores any value of intelligence and ability to pass down knowledge, which is definitely a fitness factor just for being able to prevent future generations from poisoning themselves as easily.

Having kids takes a long time, especially when many of them die of infection or malnutrition. So yes, you're absolutely right that evolution "cares" about human beings up until they hit ~40. At that point, human beings enter the selection shadow, when improvements to survivability have a negligible impact on selection. I was eliding this point for clarity but I don't think it really alters my broader argument.

This is all pretty obvious when you look at one of the main diseases of aging, cardiovascular disease. There are natural genetic variations that result in very low free LDL blood levels, which basically prevents artherosclerosis from every developing and which inspired the development of the PCSK-9 inhibitors. However, there's no evolutionary benefit to not dying of cardiac arrest when you're 60, but there are marginal benefits to the liver binding to fewer LDL particles when people are in a starvation environment, so these variations never became widespread.

The grandparent hypothesis is certainly compelling and might explain some marginal improvements in human lifespan relative to e.g. chimps (who live about 10-20 years less than us even in captivity). But if anything, that reinforces my broader point, which is that aging did not develop as some kind of culling agent by evolution and that we should be looking for ways to extend human longevity now that we have the resources to.

Death is a natural sweeper that allows progress, evolution, rapid change and adjustment to new situations. The opposite brings, well, the opposite.

The life well lived is a life thats easy to let go, regardless of your beliefs. The more people messed up the more they desperately cling to it (I know its vastly more complex, but this is the core of what I see around).

I am not claiming we shouldn't be trying to make lives better, or longer. But immortality will be humanity's doom - there is endless row of puttin' and trumps and hitlers and stalins and maos in every single generation, and the only real working solution is inevitable death, none of them went or will let go power on their own from the bottom of their good hearts. That is unavoidable since it comes from base character of humans, whether we like it or not.

I'd say we should shoot on sight all researchers and VCs pouring time and money into directly immortality, that's much safer bet than some immortality bringing long term prosperity for mankind.

I think those 70–80 year old politicians would be much less short-sighted if they expected to be around to reap what they're sowing.

That's a nice theory but I don't want to bet future of mankind on some feel-good logic. In my view, a-holes remain a-holes, self-centered narcissists double so.

Feel like trump for example got wiser and saner and more rational the second term? Because literally whole world believes otherwise. He has his whole clan to think of due to consequences of his actions, if he cared. puttin' is same, just sour keg of bad beer that should be poured down the river (or some better ecological disposal of garbage).

Why do you think 70-80 year old "middle aged" politicians would get a chance when 150 year old "boomers" with wealth and powerful networks might be able to call the the shots?

> Is aging bad though? Seems like natures way of helping humanity evolve.

We're not undoing death, dying healthy would be better than aging the way we do right now.

Increasing healthspans as a society would be great in a more family integrated society rather than an individualistic one.

I'd love my retirement years to be spent helping my kids and grand-kids instead of the other way around.

A senior community that can stay involved actively has been part of the "it takes a village" until very recent times.

What interest I have in anti-aging is less about living forever than alleviating suffering on the way out. Living to 80, 90 or 100 seems like plenty of time on earth but making that last half of our lives less achey, infirmed and delirious is a noble goal.

I rather think that terms like "nature" or "evolve" are better at describing what has happened rather than some guidelines to adhere to.

One could say air conditioning is similarly "unnatural" but it will be saving lives this summer.

That is a much more philosophical point than I was trying to make, but it definitely raises some interesting questions.

By that logic, why not just execute everyone over 35? They're just slowing down human progress.

Aging doesn't exist because it benefits us, we did not choose 70-80 to be the ideal lifespan, and my back doesn't continuously ache to give new ideas a chance to spring forth.

> For example: see 70-80 year old politicians ageist assault on future generations.

Sure but that's because the US voting demographic is old. It's the tyranny of the majority [1]; as the largest generation the baby boomers can vote and do vote for things that advance their interest. I'm not sure this phenomenon works if people live out to 150 years as the generational bubbles would be relatively smaller.

[1]: https://en.wikipedia.org/wiki/Tyranny_of_the_majority